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crypto: authenc - Find proper IV address in ablkcipher callback#3

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noglitch merged 1 commit intolinux4sam:masterfrom
karlhiramoto:linux-3.6.9-cryptofixes
Dec 19, 2013
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crypto: authenc - Find proper IV address in ablkcipher callback#3
noglitch merged 1 commit intolinux4sam:masterfrom
karlhiramoto:linux-3.6.9-cryptofixes

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@karlhiramoto
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When performing an asynchronous ablkcipher operation the authenc
completion callback routine is invoked, but it does not locate and use
the proper IV.

The callback routine, crypto_authenc_encrypt_done, is updated to use
the same method of calculating the address of the IV as is done in
crypto_authenc_encrypt function which sets up the callback.

Cc: stable@vger.kernel.org
Signed-off-by: Tom Lendacky thomas.lendacky@amd.com
Signed-off-by: Herbert Xu herbert@gondor.apana.org.au

When performing an asynchronous ablkcipher operation the authenc
completion callback routine is invoked, but it does not locate and use
the proper IV.

The callback routine, crypto_authenc_encrypt_done, is updated to use
the same method of calculating the address of the IV as is done in
crypto_authenc_encrypt function which sets up the callback.

Cc: stable@vger.kernel.org
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
@karlhiramoto
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Hi, this is a cherry pick from https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=fc019c7122dfcd69c50142b57a735539aec5da95

Without this patch "modprobe tcrypt alg='authenc(hmac(sha1),cbc(aes))' type=3 " will fail.
IPSec connections may fail too.

noglitch added a commit that referenced this pull request Dec 19, 2013
crypto: authenc - Find proper IV address in ablkcipher callback
@noglitch noglitch merged commit 2cdb575 into linux4sam:master Dec 19, 2013
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Thanks a lot Karl for this "heads-up", I will also integrate it in our 3.10-based branch before it hits -stable

Best regards,

Nicolas Ferre

noglitch pushed a commit that referenced this pull request May 13, 2014
Lockdep reports:

=============================================
[ INFO: possible recursive locking detected ]
3.9.0+ #3 Not tainted
---------------------------------------------
setquota/28368 is trying to acquire lock:
 (sb_internal){++++.?}, at: [<c11e8846>] xfs_trans_alloc+0x26/0x50

but task is already holding lock:
 (sb_internal){++++.?}, at: [<c11e8846>] xfs_trans_alloc+0x26/0x50

from xfs_qm_scall_setqlim()->xfs_dqread() when a dquot needs to be
allocated.

xfs_qm_scall_setqlim() is starting a transaction and then not
passing it into xfs_qm_dqet() and so it starts it's own transaction
when allocating the dquot.  Splat!

Fix this by not allocating the dquot in xfs_qm_scall_setqlim()
inside the setqlim transaction. This requires getting the dquot
first (and allocating it if necessary) then dropping and relocking
the dquot before joining it to the setqlim transaction.

Reported-by: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
Commit 86a9668
"[SCSI] zfcp: support for hardware data router"
reduced the initial block queue limits in the scsi_host_template to the
absolute minimum and adjusted them later on. However, the adjustment was
too late for the BSG devices of Scsi_Host and fc_host.

Therefore, ioctl(..., SG_IO, ...) with request or response size > 4kB to a
BSG device of an fc_host or a Scsi_Host fails with EINVAL. As a result,
users of such ioctl such as HBA_SendCTPassThru() in libzfcphbaapi return
with error HBA_STATUS_ERROR.

Initialize the block queue limits in zfcp_scsi_host_template to the
greatest common denominator (GCD).

While we cannot exploit the slightly enlarged maximum request size with
data router, this should be neglectible. Doing so also avoids running into
trouble after live guest relocation (LGR) / migration from a data router
FCP device to an FCP device that does not support data router. In that
case, zfcp would figure out the new limits on adapter recovery, but the
fc_host and Scsi_Host (plus in fact all sdevs) still exist with the old and
now too large queue limits.

It should also OK, not to use half the size as in the DIX case, because
fc_host and Scsi_Host do not transport FCP requests including SCSI commands
using protection data.

Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> #3.2+
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
Got bellow lockdep warning during tests. It is false alarm though.

[ 1184.479097] =============================================
[ 1184.479187] [ INFO: possible recursive locking detected ]
[ 1184.479277] 3.10.0-rc3+ #13 Tainted: G         C
[ 1184.479355] ---------------------------------------------
[ 1184.479444] mkdir/2215 is trying to acquire lock:
[ 1184.479521]  (&(&dentry->d_lock)->rlock){+.+...}, at: [<ffffffffa06cc27c>] ll_md_blocking_ast+0x55c/0x655 [lustre]
[ 1184.479801]
but task is already holding lock:
[ 1184.479895]  (&(&dentry->d_lock)->rlock){+.+...}, at: [<ffffffffa06cc1b1>] ll_md_blocking_ast+0x491/0x655 [lustre]
[ 1184.480101]
other info that might help us debug this:
[ 1184.480206]  Possible unsafe locking scenario:

[ 1184.480300]        CPU0
[ 1184.480340]        ----
[ 1184.480380]   lock(&(&dentry->d_lock)->rlock);
[ 1184.480458]   lock(&(&dentry->d_lock)->rlock);
[ 1184.480536]
 *** DEADLOCK ***

[ 1184.480761]  May be due to missing lock nesting notation

[ 1184.480936] 4 locks held by mkdir/2215:
[ 1184.481037]  #0:  (sb_writers#11){.+.+.+}, at: [<ffffffff811531a9>] mnt_want_write+0x24/0x4b
[ 1184.481273]  #1:  (&type->i_mutex_dir_key#3/1){+.+.+.}, at: [<ffffffff81144fce>] kern_path_create+0x8c/0x144
[ 1184.481513]  #2:  (&sb->s_type->i_lock_key#19){+.+...}, at: [<ffffffffa06cc180>] ll_md_blocking_ast+0x460/0x655 [lustre]
[ 1184.481778]  #3:  (&(&dentry->d_lock)->rlock){+.+...}, at: [<ffffffffa06cc1b1>] ll_md_blocking_ast+0x491/0x655 [lustre]
[ 1184.482050]

Signed-off-by: Peng Tao <tao.peng@emc.com>
Signed-off-by: Andreas Dilger <andreas.dilger@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
Under ARM64, PTEs can be broadly categorised as follows:
   - Present and valid: Bit #0 is set. The PTE is valid and memory
     access to the region may fault.

   - Present and invalid: Bit #0 is clear and bit #1 is set.
     Represents present memory with PROT_NONE protection. The PTE
     is an invalid entry, and the user fault handler will raise a
     SIGSEGV.

   - Not present (file or swap): Bits #0 and #1 are clear.
     Memory represented has been paged out. The PTE is an invalid
     entry, and the fault handler will try and re-populate the
     memory where necessary.

Huge PTEs are block descriptors that have bit #1 clear. If we wish
to represent PROT_NONE huge PTEs we then run into a problem as
there is no way to distinguish between regular and huge PTEs if we
set bit #1.

To resolve this ambiguity this patch moves PTE_PROT_NONE from
bit #1 to bit #2 and moves PTE_FILE from bit #2 to bit #3. The
number of swap/file bits is reduced by 1 as a consequence, leaving
60 bits for file and swap entries.

Signed-off-by: Steve Capper <steve.capper@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
Don't sleep in __fscache_maybe_release_page() if __GFP_FS is not set.  This
goes some way towards mitigating fscache deadlocking against ext4 by way of
the allocator, eg:

INFO: task flush-8:0:24427 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
flush-8:0       D ffff88003e2b9fd8     0 24427      2 0x00000000
 ffff88003e2b9138 0000000000000046 ffff880012e3a040 ffff88003e2b9fd8
 0000000000011c80 ffff88003e2b9fd8 ffffffff81a10400 ffff880012e3a040
 0000000000000002 ffff880012e3a040 ffff88003e2b9098 ffffffff8106dcf5
Call Trace:
 [<ffffffff8106dcf5>] ? __lock_is_held+0x31/0x53
 [<ffffffff81219b61>] ? radix_tree_lookup_element+0xf4/0x12a
 [<ffffffff81454bed>] schedule+0x60/0x62
 [<ffffffffa01d349c>] __fscache_wait_on_page_write+0x8b/0xa5 [fscache]
 [<ffffffff810498a8>] ? __init_waitqueue_head+0x4d/0x4d
 [<ffffffffa01d393a>] __fscache_maybe_release_page+0x30c/0x324 [fscache]
 [<ffffffffa01d369a>] ? __fscache_maybe_release_page+0x6c/0x324 [fscache]
 [<ffffffff81071b53>] ? trace_hardirqs_on_caller+0x114/0x170
 [<ffffffffa01fd7b2>] nfs_fscache_release_page+0x68/0x94 [nfs]
 [<ffffffffa01ef73e>] nfs_release_page+0x7e/0x86 [nfs]
 [<ffffffff810aa553>] try_to_release_page+0x32/0x3b
 [<ffffffff810b6c70>] shrink_page_list+0x535/0x71a
 [<ffffffff81071b53>] ? trace_hardirqs_on_caller+0x114/0x170
 [<ffffffff810b7352>] shrink_inactive_list+0x20a/0x2dd
 [<ffffffff81071a13>] ? mark_held_locks+0xbe/0xea
 [<ffffffff810b7a65>] shrink_lruvec+0x34c/0x3eb
 [<ffffffff810b7bd3>] do_try_to_free_pages+0xcf/0x355
 [<ffffffff810b7fc8>] try_to_free_pages+0x9a/0xa1
 [<ffffffff810b08d2>] __alloc_pages_nodemask+0x494/0x6f7
 [<ffffffff810d9a07>] kmem_getpages+0x58/0x155
 [<ffffffff810dc002>] fallback_alloc+0x120/0x1f3
 [<ffffffff8106db23>] ? trace_hardirqs_off+0xd/0xf
 [<ffffffff810dbed3>] ____cache_alloc_node+0x177/0x186
 [<ffffffff81162a6c>] ? ext4_init_io_end+0x1c/0x37
 [<ffffffff810dc403>] kmem_cache_alloc+0xf1/0x176
 [<ffffffff810b17ac>] ? test_set_page_writeback+0x101/0x113
 [<ffffffff81162a6c>] ext4_init_io_end+0x1c/0x37
 [<ffffffff81162ce4>] ext4_bio_write_page+0x20f/0x3af
 [<ffffffff8115cc02>] mpage_da_submit_io+0x26e/0x2f6
 [<ffffffff811088e5>] ? __find_get_block_slow+0x38/0x133
 [<ffffffff81161348>] mpage_da_map_and_submit+0x3a7/0x3bd
 [<ffffffff81161a60>] ext4_da_writepages+0x30d/0x426
 [<ffffffff810b3359>] do_writepages+0x1c/0x2a
 [<ffffffff81102f4d>] __writeback_single_inode+0x3e/0xe5
 [<ffffffff81103995>] writeback_sb_inodes+0x1bd/0x2f4
 [<ffffffff81103b3b>] __writeback_inodes_wb+0x6f/0xb4
 [<ffffffff81103c81>] wb_writeback+0x101/0x195
 [<ffffffff81071b53>] ? trace_hardirqs_on_caller+0x114/0x170
 [<ffffffff811043aa>] ? wb_do_writeback+0xaa/0x173
 [<ffffffff8110434a>] wb_do_writeback+0x4a/0x173
 [<ffffffff81071bbc>] ? trace_hardirqs_on+0xd/0xf
 [<ffffffff81038554>] ? del_timer+0x4b/0x5b
 [<ffffffff811044e0>] bdi_writeback_thread+0x6d/0x147
 [<ffffffff81104473>] ? wb_do_writeback+0x173/0x173
 [<ffffffff81048fbc>] kthread+0xd0/0xd8
 [<ffffffff81455eb2>] ? _raw_spin_unlock_irq+0x29/0x3e
 [<ffffffff81048eec>] ? __init_kthread_worker+0x55/0x55
 [<ffffffff81456aac>] ret_from_fork+0x7c/0xb0
 [<ffffffff81048eec>] ? __init_kthread_worker+0x55/0x55
2 locks held by flush-8:0/24427:
 #0:  (&type->s_umount_key#41){.+.+..}, at: [<ffffffff810e3b73>] grab_super_passive+0x4c/0x76
 #1:  (jbd2_handle){+.+...}, at: [<ffffffff81190d81>] start_this_handle+0x475/0x4ea


The problem here is that another thread, which is attempting to write the
to-be-stored NFS page to the on-ext4 cache file is waiting for the journal
lock, eg:

INFO: task kworker/u:2:24437 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u:2     D ffff880039589768     0 24437      2 0x00000000
 ffff8800395896d8 0000000000000046 ffff8800283bf040 ffff880039589fd8
 0000000000011c80 ffff880039589fd8 ffff880039f0b040 ffff8800283bf040
 0000000000000006 ffff8800283bf6b8 ffff880039589658 ffffffff81071a13
Call Trace:
 [<ffffffff81071a13>] ? mark_held_locks+0xbe/0xea
 [<ffffffff81455e73>] ? _raw_spin_unlock_irqrestore+0x3a/0x50
 [<ffffffff81071b53>] ? trace_hardirqs_on_caller+0x114/0x170
 [<ffffffff81071bbc>] ? trace_hardirqs_on+0xd/0xf
 [<ffffffff81454bed>] schedule+0x60/0x62
 [<ffffffff81190c23>] start_this_handle+0x317/0x4ea
 [<ffffffff810498a8>] ? __init_waitqueue_head+0x4d/0x4d
 [<ffffffff81190fcc>] jbd2__journal_start+0xb3/0x12e
 [<ffffffff81176606>] __ext4_journal_start_sb+0xb2/0xc6
 [<ffffffff8115f137>] ext4_da_write_begin+0x109/0x233
 [<ffffffff810a964d>] generic_file_buffered_write+0x11a/0x264
 [<ffffffff811032cf>] ? __mark_inode_dirty+0x2d/0x1ee
 [<ffffffff810ab1ab>] __generic_file_aio_write+0x2a5/0x2d5
 [<ffffffff810ab24a>] generic_file_aio_write+0x6f/0xd0
 [<ffffffff81159a2c>] ext4_file_write+0x38c/0x3c4
 [<ffffffff810e0915>] do_sync_write+0x91/0xd1
 [<ffffffffa00a17f0>] cachefiles_write_page+0x26f/0x310 [cachefiles]
 [<ffffffffa01d470b>] fscache_write_op+0x21e/0x37a [fscache]
 [<ffffffff81455eb2>] ? _raw_spin_unlock_irq+0x29/0x3e
 [<ffffffffa01d2479>] fscache_op_work_func+0x78/0xd7 [fscache]
 [<ffffffff8104455a>] process_one_work+0x232/0x3a8
 [<ffffffff810444ff>] ? process_one_work+0x1d7/0x3a8
 [<ffffffff81044ee0>] worker_thread+0x214/0x303
 [<ffffffff81044ccc>] ? manage_workers+0x245/0x245
 [<ffffffff81048fbc>] kthread+0xd0/0xd8
 [<ffffffff81455eb2>] ? _raw_spin_unlock_irq+0x29/0x3e
 [<ffffffff81048eec>] ? __init_kthread_worker+0x55/0x55
 [<ffffffff81456aac>] ret_from_fork+0x7c/0xb0
 [<ffffffff81048eec>] ? __init_kthread_worker+0x55/0x55
4 locks held by kworker/u:2/24437:
 #0:  (fscache_operation){.+.+.+}, at: [<ffffffff810444ff>] process_one_work+0x1d7/0x3a8
 #1:  ((&op->work)){+.+.+.}, at: [<ffffffff810444ff>] process_one_work+0x1d7/0x3a8
 #2:  (sb_writers#14){.+.+.+}, at: [<ffffffff810ab22c>] generic_file_aio_write+0x51/0xd0
 #3:  (&sb->s_type->i_mutex_key#19){+.+.+.}, at: [<ffffffff810ab236>] generic_file_aio_write+0x5b/0x

fscache already tries to cancel pending stores, but it can't cancel a write
for which I/O is already in progress.

An alternative would be to accept writing garbage to the cache under extreme
circumstances and to kill the afflicted cache object if we have to do this.
However, we really need to know how strapped the allocator is before deciding
to do that.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-By: Milosz Tanski <milosz@adfin.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
This is trickier than prev two:

* context switching code saves kernel mode callee regs in the format of
  struct callee_regs thus needs adjustment. This also reduces the height
  of topmost kernel stack frame by 1 word.

* Since kernel stack unwinder is sensitive to height of topmost kernel
  stack frame, that needs a word of adjustment too.

ptrace needs a bit of updating since pt_regs now diverges from
user_regs_struct.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
The PCIe code has an array of buffer descriptors (RXBs) that have pages
and DMA mappings attached. In regular use, the array isn't used and the
buffers are either on the hardware receive queue or the rx_free/rx_used
lists for recycling.

Occasionally, during module unload, we'd see a warning from this:

WARNING: at lib/list_debug.c:32 __list_add+0x91/0xa0()
list_add corruption. prev->next should be next (c31c98cc), but was c31c80bc. (prev=c31c80bc).
Pid: 519, comm: rmmod Tainted: G        W  O 3.4.24-dev #3
Call Trace:
 [<c10335b2>] warn_slowpath_common+0x72/0xa0
 [<c1033683>] warn_slowpath_fmt+0x33/0x40
 [<c12e31d1>] __list_add+0x91/0xa0
 [<fdf2083c>] iwl_pcie_rxq_free_rbs+0xcc/0xe0 [iwlwifi]
 [<fdf21b3f>] iwl_pcie_rx_free+0x3f/0x210 [iwlwifi]
 [<fdf2dd7a>] iwl_trans_pcie_free+0x2a/0x90 [iwlwifi]

The reason for this seems to be that in iwl_pcie_rxq_free_rbs() we use
the array to free all buffers (the hardware receive queue isn't in use
any more at this point). The function also adds all buffers to rx_used
because it's also used during initialisation (when no freeing happens.)
This can cause the warning because it may add entries to the list that
are already on it. Luckily, this is harmless because it can only happen
when the entire data structure is freed anyway, since during init both
lists are initialized from scratch.

Disentangle this code and treat init and free separately. During init
we just need to put them onto the list after freeing all buffers (for
switching between 4k/8k buffers); during free no list manipulations
are necessary at all.

Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
eb178d0 ("cgroup: grab cgroup_mutex in
drop_parsed_module_refcounts()") made drop_parsed_module_refcounts()
grab cgroup_mutex to make lockdep assertion in for_each_subsys()
happy.  Unfortunately, cgroup_remount() calls the function while
holding cgroup_mutex in its failure path leading to the following
deadlock.

# mount -t cgroup -o remount,memory,blkio cgroup blkio

 cgroup: option changes via remount are deprecated (pid=525 comm=mount)

 =============================================
 [ INFO: possible recursive locking detected ]
 3.10.0-rc4-work+ #1 Not tainted
 ---------------------------------------------
 mount/525 is trying to acquire lock:
  (cgroup_mutex){+.+.+.}, at: [<ffffffff8110a3e1>] drop_parsed_module_refcounts+0x21/0xb0

 but task is already holding lock:
  (cgroup_mutex){+.+.+.}, at: [<ffffffff8110e4e1>] cgroup_remount+0x51/0x200

 other info that might help us debug this:
  Possible unsafe locking scenario:

	CPU0
	----
   lock(cgroup_mutex);
   lock(cgroup_mutex);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 4 locks held by mount/525:
  #0:  (&type->s_umount_key#30){+.+...}, at: [<ffffffff811e9a0d>] do_mount+0x2bd/0xa30
  #1:  (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [<ffffffff8110e4d3>] cgroup_remount+0x43/0x200
  #2:  (cgroup_mutex){+.+.+.}, at: [<ffffffff8110e4e1>] cgroup_remount+0x51/0x200
  #3:  (cgroup_root_mutex){+.+.+.}, at: [<ffffffff8110e4ef>] cgroup_remount+0x5f/0x200

 stack backtrace:
 CPU: 2 PID: 525 Comm: mount Not tainted 3.10.0-rc4-work+ #1
 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
  ffffffff829651f0 ffff88000ec2fc28 ffffffff81c24bb1 ffff88000ec2fce8
  ffffffff810f420d 0000000000000006 0000000000000001 0000000000000056
  ffff8800153b4640 ffff880000000000 ffffffff81c2e468 ffff8800153b4640
 Call Trace:
  [<ffffffff81c24bb1>] dump_stack+0x19/0x1b
  [<ffffffff810f420d>] __lock_acquire+0x15dd/0x1e60
  [<ffffffff810f531c>] lock_acquire+0x9c/0x1f0
  [<ffffffff81c2a805>] mutex_lock_nested+0x65/0x410
  [<ffffffff8110a3e1>] drop_parsed_module_refcounts+0x21/0xb0
  [<ffffffff8110e63e>] cgroup_remount+0x1ae/0x200
  [<ffffffff811c9bb2>] do_remount_sb+0x82/0x190
  [<ffffffff811e9d41>] do_mount+0x5f1/0xa30
  [<ffffffff811ea203>] SyS_mount+0x83/0xc0
  [<ffffffff81c2fb82>] system_call_fastpath+0x16/0x1b

Fix it by moving the drop_parsed_module_refcounts() invocation outside
cgroup_mutex.

Signed-off-by: Tejun Heo <tj@kernel.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
…/kernel/git/vgupta/arc

Pull first batch of ARC changes from Vineet Gupta:
 "There's a second bunch to follow next week - which depends on commits
  on other trees (irq/net).  I'd have preferred the accompanying ARC
  change via respective trees, but it didn't workout somehow.

  Highlights of changes:

   - Continuation of ARC MM changes from 3.10 including

       zero page optimization
       Setting pagecache pages dirty by default
       Non executable stack by default
       Reducing dcache flushes for aliasing VIPT config

   - Long overdue rework of pt_regs machinery - removing the unused word
     gutters and adding ECR register to baseline (helps cleanup lot of
     low level code)

   - Support for ARC gcc 4.8

   - Few other preventive fixes, cosmetics, usage of Kconfig helper..

  The diffstat is larger than normal primarily because of arcregs.h
  header split as well as beautification of macros in entry.h"

* tag 'arc-v3.11-rc1-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (32 commits)
  ARC: warn on improper stack unwind FDE entries
  arc: delete __cpuinit usage from all arc files
  ARC: [tlb-miss] Fix bug with CONFIG_ARC_DBG_TLB_MISS_COUNT
  ARC: [tlb-miss] Extraneous PTE bit testing/setting
  ARC: Adjustments for gcc 4.8
  ARC: Setup Vector Table Base in early boot
  ARC: Remove explicit passing around of ECR
  ARC: pt_regs update #5: Use real ECR for pt_regs->event vs. synth values
  ARC: stop using pt_regs->orig_r8
  ARC: pt_regs update #4: r25 saved/restored unconditionally
  ARC: K/U SP saved from one location in stack switching macro
  ARC: Entry Handler tweaks: Simplify branch for in-kernel preemption
  ARC: Entry Handler tweaks: Avoid hardcoded LIMMS for ECR values
  ARC: Increase readability of entry handlers
  ARC: pt_regs update #3: Remove unused gutter at start of callee_regs
  ARC: pt_regs update #2: Remove unused gutter at start of pt_regs
  ARC: pt_regs update #1: Align pt_regs end with end of kernel stack page
  ARC: pt_regs update #0: remove kernel stack canary
  ARC: [mm] Remove @Write argument to do_page_fault()
  ARC: [mm] Make stack/heap Non-executable by default
  ...
noglitch pushed a commit that referenced this pull request May 13, 2014
When kernel is compiled with CONFIG_SLUB_DEBUG=y and
CRYPTO_MANAGER_DISABLE_TESTS=n, during kernel bootup, the kernel
reports error given below. The root cause is that in function
hash_digest_key(), for allocating descriptor, insufficient memory was
being allocated. The required number of descriptor words apart from
input and output pointers are 8 (instead of 6).

=============================================================================
BUG dma-kmalloc-32 (Not tainted): Redzone overwritten
-----------------------------------------------------------------------------

Disabling lock debugging due to kernel taint
INFO: 0xdec5dec0-0xdec5dec3. First byte 0x0 instead of 0xcc
INFO: Allocated in ahash_setkey+0x60/0x594 age=7 cpu=1 pid=1257
        __kmalloc+0x154/0x1b4
        ahash_setkey+0x60/0x594
        test_hash+0x260/0x5a0
        alg_test_hash+0x48/0xb0
        alg_test+0x84/0x228
        cryptomgr_test+0x4c/0x54
        kthread+0x98/0x9c
        ret_from_kernel_thread+0x64/0x6c
INFO: Slab 0xc0bd0ba0 objects=19 used=2 fp=0xdec5d0d0 flags=0x0081
INFO: Object 0xdec5dea0 @offset=3744 fp=0x5c200014

Bytes b4 dec5de90: 00 00 00 00 00 00 00 00 5a 5a 5a 5a 5a 5a 5a 5a
........ZZZZZZZZ
Object dec5dea0: b0 80 00 0a 84 41 00 0d f0 40 00 00 00 67 3f c0
.....A...@...g?.
Object dec5deb0: 00 00 00 50 2c 14 00 50 f8 40 00 00 1e c5 d0 00
...P,..P.@......
Redzone dec5dec0: 00 00 00 14                                      ....
Padding dec5df68: 5a 5a 5a 5a 5a 5a 5a 5a
ZZZZZZZZ
Call Trace:
[dec65b60] [c00071b4] show_stack+0x4c/0x168 (unreliable)
[dec65ba0] [c00d4ec8] check_bytes_and_report+0xe4/0x11c
[dec65bd0] [c00d507c] check_object+0x17c/0x23c
[dec65bf0] [c0550a00] free_debug_processing+0xf4/0x294
[dec65c20] [c0550bdc] __slab_free+0x3c/0x294
[dec65c80] [c03f0744] ahash_setkey+0x4e0/0x594
[dec65cd0] [c01ef138] test_hash+0x260/0x5a0
[dec65e50] [c01ef4c0] alg_test_hash+0x48/0xb0
[dec65e70] [c01eecc4] alg_test+0x84/0x228
[dec65ee0] [c01ec640] cryptomgr_test+0x4c/0x54
[dec65ef0] [c005adc0] kthread+0x98/0x9c
[dec65f40] [c000e1ac] ret_from_kernel_thread+0x64/0x6c
FIX dma-kmalloc-32: Restoring 0xdec5dec0-0xdec5dec3=0xcc

Change-Id: I0c7a1048053e811025d1c3b487940f87345c8f5d
Signed-off-by: Vakul Garg <vakul@freescale.com>
CC: <stable@vger.kernel.org> #3.9
Reviewed-by: Geanta Neag Horia Ioan-B05471 <horia.geanta@freescale.com>
Reviewed-by: Fleming Andrew-AFLEMING <AFLEMING@freescale.com>
Tested-by: Fleming Andrew-AFLEMING <AFLEMING@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
noglitch pushed a commit that referenced this pull request May 13, 2014
Jiri managed to trigger this warning:

 [] ======================================================
 [] [ INFO: possible circular locking dependency detected ]
 [] 3.10.0+ #228 Tainted: G        W
 [] -------------------------------------------------------
 [] p/6613 is trying to acquire lock:
 []  (rcu_node_0){..-...}, at: [<ffffffff810ca797>] rcu_read_unlock_special+0xa7/0x250
 []
 [] but task is already holding lock:
 []  (&ctx->lock){-.-...}, at: [<ffffffff810f2879>] perf_lock_task_context+0xd9/0x2c0
 []
 [] which lock already depends on the new lock.
 []
 [] the existing dependency chain (in reverse order) is:
 []
 [] -> #4 (&ctx->lock){-.-...}:
 [] -> #3 (&rq->lock){-.-.-.}:
 [] -> #2 (&p->pi_lock){-.-.-.}:
 [] -> #1 (&rnp->nocb_gp_wq[1]){......}:
 [] -> #0 (rcu_node_0){..-...}:

Paul was quick to explain that due to preemptible RCU we cannot call
rcu_read_unlock() while holding scheduler (or nested) locks when part
of the read side critical section was preemptible.

Therefore solve it by making the entire RCU read side non-preemptible.

Also pull out the retry from under the non-preempt to play nice with RT.

Reported-by: Jiri Olsa <jolsa@redhat.com>
Helped-out-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
commit 2f7021a "cpufreq: protect 'policy->cpus' from offlining
during __gov_queue_work()" caused a regression in CPU hotplug,
because it lead to a deadlock between cpufreq governor worker thread
and the CPU hotplug writer task.

Lockdep splat corresponding to this deadlock is shown below:

[   60.277396] ======================================================
[   60.277400] [ INFO: possible circular locking dependency detected ]
[   60.277407] 3.10.0-rc7-dbg-01385-g241fd04-dirty #1744 Not tainted
[   60.277411] -------------------------------------------------------
[   60.277417] bash/2225 is trying to acquire lock:
[   60.277422]  ((&(&j_cdbs->work)->work)){+.+...}, at: [<ffffffff810621b5>] flush_work+0x5/0x280
[   60.277444] but task is already holding lock:
[   60.277449]  (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff81042d8b>] cpu_hotplug_begin+0x2b/0x60
[   60.277465] which lock already depends on the new lock.

[   60.277472] the existing dependency chain (in reverse order) is:
[   60.277477] -> #2 (cpu_hotplug.lock){+.+.+.}:
[   60.277490]        [<ffffffff810ac6d4>] lock_acquire+0xa4/0x200
[   60.277503]        [<ffffffff815b6157>] mutex_lock_nested+0x67/0x410
[   60.277514]        [<ffffffff81042cbc>] get_online_cpus+0x3c/0x60
[   60.277522]        [<ffffffff814b842a>] gov_queue_work+0x2a/0xb0
[   60.277532]        [<ffffffff814b7891>] cs_dbs_timer+0xc1/0xe0
[   60.277543]        [<ffffffff8106302d>] process_one_work+0x1cd/0x6a0
[   60.277552]        [<ffffffff81063d31>] worker_thread+0x121/0x3a0
[   60.277560]        [<ffffffff8106ae2b>] kthread+0xdb/0xe0
[   60.277569]        [<ffffffff815bb96c>] ret_from_fork+0x7c/0xb0
[   60.277580] -> #1 (&j_cdbs->timer_mutex){+.+...}:
[   60.277592]        [<ffffffff810ac6d4>] lock_acquire+0xa4/0x200
[   60.277600]        [<ffffffff815b6157>] mutex_lock_nested+0x67/0x410
[   60.277608]        [<ffffffff814b785d>] cs_dbs_timer+0x8d/0xe0
[   60.277616]        [<ffffffff8106302d>] process_one_work+0x1cd/0x6a0
[   60.277624]        [<ffffffff81063d31>] worker_thread+0x121/0x3a0
[   60.277633]        [<ffffffff8106ae2b>] kthread+0xdb/0xe0
[   60.277640]        [<ffffffff815bb96c>] ret_from_fork+0x7c/0xb0
[   60.277649] -> #0 ((&(&j_cdbs->work)->work)){+.+...}:
[   60.277661]        [<ffffffff810ab826>] __lock_acquire+0x1766/0x1d30
[   60.277669]        [<ffffffff810ac6d4>] lock_acquire+0xa4/0x200
[   60.277677]        [<ffffffff810621ed>] flush_work+0x3d/0x280
[   60.277685]        [<ffffffff81062d8a>] __cancel_work_timer+0x8a/0x120
[   60.277693]        [<ffffffff81062e53>] cancel_delayed_work_sync+0x13/0x20
[   60.277701]        [<ffffffff814b89d9>] cpufreq_governor_dbs+0x529/0x6f0
[   60.277709]        [<ffffffff814b76a7>] cs_cpufreq_governor_dbs+0x17/0x20
[   60.277719]        [<ffffffff814b5df8>] __cpufreq_governor+0x48/0x100
[   60.277728]        [<ffffffff814b6b80>] __cpufreq_remove_dev.isra.14+0x80/0x3c0
[   60.277737]        [<ffffffff815adc0d>] cpufreq_cpu_callback+0x38/0x4c
[   60.277747]        [<ffffffff81071a4d>] notifier_call_chain+0x5d/0x110
[   60.277759]        [<ffffffff81071b0e>] __raw_notifier_call_chain+0xe/0x10
[   60.277768]        [<ffffffff815a0a68>] _cpu_down+0x88/0x330
[   60.277779]        [<ffffffff815a0d46>] cpu_down+0x36/0x50
[   60.277788]        [<ffffffff815a2748>] store_online+0x98/0xd0
[   60.277796]        [<ffffffff81452a28>] dev_attr_store+0x18/0x30
[   60.277806]        [<ffffffff811d9edb>] sysfs_write_file+0xdb/0x150
[   60.277818]        [<ffffffff8116806d>] vfs_write+0xbd/0x1f0
[   60.277826]        [<ffffffff811686fc>] SyS_write+0x4c/0xa0
[   60.277834]        [<ffffffff815bbbbe>] tracesys+0xd0/0xd5
[   60.277842] other info that might help us debug this:

[   60.277848] Chain exists of:
  (&(&j_cdbs->work)->work) --> &j_cdbs->timer_mutex --> cpu_hotplug.lock

[   60.277864]  Possible unsafe locking scenario:

[   60.277869]        CPU0                    CPU1
[   60.277873]        ----                    ----
[   60.277877]   lock(cpu_hotplug.lock);
[   60.277885]                                lock(&j_cdbs->timer_mutex);
[   60.277892]                                lock(cpu_hotplug.lock);
[   60.277900]   lock((&(&j_cdbs->work)->work));
[   60.277907]  *** DEADLOCK ***

[   60.277915] 6 locks held by bash/2225:
[   60.277919]  #0:  (sb_writers#6){.+.+.+}, at: [<ffffffff81168173>] vfs_write+0x1c3/0x1f0
[   60.277937]  #1:  (&buffer->mutex){+.+.+.}, at: [<ffffffff811d9e3c>] sysfs_write_file+0x3c/0x150
[   60.277954]  #2:  (s_active#61){.+.+.+}, at: [<ffffffff811d9ec3>] sysfs_write_file+0xc3/0x150
[   60.277972]  #3:  (x86_cpu_hotplug_driver_mutex){+.+...}, at: [<ffffffff81024cf7>] cpu_hotplug_driver_lock+0x17/0x20
[   60.277990]  #4:  (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff815a0d32>] cpu_down+0x22/0x50
[   60.278007]  #5:  (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff81042d8b>] cpu_hotplug_begin+0x2b/0x60
[   60.278023] stack backtrace:
[   60.278031] CPU: 3 PID: 2225 Comm: bash Not tainted 3.10.0-rc7-dbg-01385-g241fd04-dirty #1744
[   60.278037] Hardware name: Acer             Aspire 5741G    /Aspire 5741G    , BIOS V1.20 02/08/2011
[   60.278042]  ffffffff8204e110 ffff88014df6b9f8 ffffffff815b3d90 ffff88014df6ba38
[   60.278055]  ffffffff815b0a8d ffff880150ed3f60 ffff880150ed4770 3871c4002c8980b2
[   60.278068]  ffff880150ed4748 ffff880150ed4770 ffff880150ed3f60 ffff88014df6bb00
[   60.278081] Call Trace:
[   60.278091]  [<ffffffff815b3d90>] dump_stack+0x19/0x1b
[   60.278101]  [<ffffffff815b0a8d>] print_circular_bug+0x2b6/0x2c5
[   60.278111]  [<ffffffff810ab826>] __lock_acquire+0x1766/0x1d30
[   60.278123]  [<ffffffff81067e08>] ? __kernel_text_address+0x58/0x80
[   60.278134]  [<ffffffff810ac6d4>] lock_acquire+0xa4/0x200
[   60.278142]  [<ffffffff810621b5>] ? flush_work+0x5/0x280
[   60.278151]  [<ffffffff810621ed>] flush_work+0x3d/0x280
[   60.278159]  [<ffffffff810621b5>] ? flush_work+0x5/0x280
[   60.278169]  [<ffffffff810a9b14>] ? mark_held_locks+0x94/0x140
[   60.278178]  [<ffffffff81062d77>] ? __cancel_work_timer+0x77/0x120
[   60.278188]  [<ffffffff810a9cbd>] ? trace_hardirqs_on_caller+0xfd/0x1c0
[   60.278196]  [<ffffffff81062d8a>] __cancel_work_timer+0x8a/0x120
[   60.278206]  [<ffffffff81062e53>] cancel_delayed_work_sync+0x13/0x20
[   60.278214]  [<ffffffff814b89d9>] cpufreq_governor_dbs+0x529/0x6f0
[   60.278225]  [<ffffffff814b76a7>] cs_cpufreq_governor_dbs+0x17/0x20
[   60.278234]  [<ffffffff814b5df8>] __cpufreq_governor+0x48/0x100
[   60.278244]  [<ffffffff814b6b80>] __cpufreq_remove_dev.isra.14+0x80/0x3c0
[   60.278255]  [<ffffffff815adc0d>] cpufreq_cpu_callback+0x38/0x4c
[   60.278265]  [<ffffffff81071a4d>] notifier_call_chain+0x5d/0x110
[   60.278275]  [<ffffffff81071b0e>] __raw_notifier_call_chain+0xe/0x10
[   60.278284]  [<ffffffff815a0a68>] _cpu_down+0x88/0x330
[   60.278292]  [<ffffffff81024cf7>] ? cpu_hotplug_driver_lock+0x17/0x20
[   60.278302]  [<ffffffff815a0d46>] cpu_down+0x36/0x50
[   60.278311]  [<ffffffff815a2748>] store_online+0x98/0xd0
[   60.278320]  [<ffffffff81452a28>] dev_attr_store+0x18/0x30
[   60.278329]  [<ffffffff811d9edb>] sysfs_write_file+0xdb/0x150
[   60.278337]  [<ffffffff8116806d>] vfs_write+0xbd/0x1f0
[   60.278347]  [<ffffffff81185950>] ? fget_light+0x320/0x4b0
[   60.278355]  [<ffffffff811686fc>] SyS_write+0x4c/0xa0
[   60.278364]  [<ffffffff815bbbbe>] tracesys+0xd0/0xd5
[   60.280582] smpboot: CPU 1 is now offline

The intention of that commit was to avoid warnings during CPU
hotplug, which indicated that offline CPUs were getting IPIs from the
cpufreq governor's work items.  But the real root-cause of that
problem was commit a66b2e5 (cpufreq: Preserve sysfs files across
suspend/resume) because it totally skipped all the cpufreq callbacks
during CPU hotplug in the suspend/resume path, and hence it never
actually shut down the cpufreq governor's worker threads during CPU
offline in the suspend/resume path.

Reflecting back, the reason why we never suspected that commit as the
root-cause earlier, was that the original issue was reported with
just the halt command and nobody had brought in suspend/resume to the
equation.

The reason for _that_ in turn, as it turns out, is that earlier
halt/shutdown was being done by disabling non-boot CPUs while tasks
were frozen, just like suspend/resume....  but commit cf7df37
(reboot: migrate shutdown/reboot to boot cpu) which came somewhere
along that very same time changed that logic: shutdown/halt no longer
takes CPUs offline.  Thus, the test-cases for reproducing the bug
were vastly different and thus we went totally off the trail.

Overall, it was one hell of a confusion with so many commits
affecting each other and also affecting the symptoms of the problems
in subtle ways.  Finally, now since the original problematic commit
(a66b2e5) has been completely reverted, revert this intermediate fix
too (2f7021a), to fix the CPU hotplug deadlock.  Phew!

Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Tested-by: Peter Wu <lekensteyn@gmail.com>
Cc: 3.10+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
Commits 6a1c068 and
9356b53, respectively
  'tty: Convert termios_mutex to termios_rwsem' and
  'n_tty: Access termios values safely'
introduced a circular lock dependency with console_lock and
termios_rwsem.

The lockdep report [1] shows that n_tty_write() will attempt
to claim console_lock while holding the termios_rwsem, whereas
tty_do_resize() may already hold the console_lock while
claiming the termios_rwsem.

Since n_tty_write() and tty_do_resize() do not contend
over the same data -- the tty->winsize structure -- correct
the lock dependency by introducing a new lock which
specifically serializes access to tty->winsize only.

[1] Lockdep report

======================================================
[ INFO: possible circular locking dependency detected ]
3.10.0-0+tip-xeon+lockdep #0+tip Not tainted
-------------------------------------------------------
modprobe/277 is trying to acquire lock:
 (&tty->termios_rwsem){++++..}, at: [<ffffffff81452656>] tty_do_resize+0x36/0xe0

but task is already holding lock:
 ((fb_notifier_list).rwsem){.+.+.+}, at: [<ffffffff8107aac6>] __blocking_notifier_call_chain+0x56/0xc0

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 ((fb_notifier_list).rwsem){.+.+.+}:
       [<ffffffff810b6d62>] lock_acquire+0x92/0x1f0
       [<ffffffff8175b797>] down_read+0x47/0x5c
       [<ffffffff8107aac6>] __blocking_notifier_call_chain+0x56/0xc0
       [<ffffffff8107ab46>] blocking_notifier_call_chain+0x16/0x20
       [<ffffffff813d7c0b>] fb_notifier_call_chain+0x1b/0x20
       [<ffffffff813d95b2>] register_framebuffer+0x1e2/0x320
       [<ffffffffa01043e1>] drm_fb_helper_initial_config+0x371/0x540 [drm_kms_helper]
       [<ffffffffa01bcb05>] nouveau_fbcon_init+0x105/0x140 [nouveau]
       [<ffffffffa01ad0af>] nouveau_drm_load+0x43f/0x610 [nouveau]
       [<ffffffffa008a79e>] drm_get_pci_dev+0x17e/0x2a0 [drm]
       [<ffffffffa01ad4da>] nouveau_drm_probe+0x25a/0x2a0 [nouveau]
       [<ffffffff813b13db>] local_pci_probe+0x4b/0x80
       [<ffffffff813b1701>] pci_device_probe+0x111/0x120
       [<ffffffff814977eb>] driver_probe_device+0x8b/0x3a0
       [<ffffffff81497bab>] __driver_attach+0xab/0xb0
       [<ffffffff814956ad>] bus_for_each_dev+0x5d/0xa0
       [<ffffffff814971fe>] driver_attach+0x1e/0x20
       [<ffffffff81496cc1>] bus_add_driver+0x111/0x290
       [<ffffffff814982b7>] driver_register+0x77/0x170
       [<ffffffff813b0454>] __pci_register_driver+0x64/0x70
       [<ffffffffa008a9da>] drm_pci_init+0x11a/0x130 [drm]
       [<ffffffffa022a04d>] nouveau_drm_init+0x4d/0x1000 [nouveau]
       [<ffffffff810002ea>] do_one_initcall+0xea/0x1a0
       [<ffffffff810c54cb>] load_module+0x123b/0x1bf0
       [<ffffffff810c5f57>] SyS_init_module+0xd7/0x120
       [<ffffffff817677c2>] system_call_fastpath+0x16/0x1b

-> #1 (console_lock){+.+.+.}:
       [<ffffffff810b6d62>] lock_acquire+0x92/0x1f0
       [<ffffffff810430a7>] console_lock+0x77/0x80
       [<ffffffff8146b2a1>] con_flush_chars+0x31/0x50
       [<ffffffff8145780c>] n_tty_write+0x1ec/0x4d0
       [<ffffffff814541b9>] tty_write+0x159/0x2e0
       [<ffffffff814543f5>] redirected_tty_write+0xb5/0xc0
       [<ffffffff811ab9d5>] vfs_write+0xc5/0x1f0
       [<ffffffff811abec5>] SyS_write+0x55/0xa0
       [<ffffffff817677c2>] system_call_fastpath+0x16/0x1b

-> #0 (&tty->termios_rwsem){++++..}:
       [<ffffffff810b65c3>] __lock_acquire+0x1c43/0x1d30
       [<ffffffff810b6d62>] lock_acquire+0x92/0x1f0
       [<ffffffff8175b724>] down_write+0x44/0x70
       [<ffffffff81452656>] tty_do_resize+0x36/0xe0
       [<ffffffff8146c841>] vc_do_resize+0x3e1/0x4c0
       [<ffffffff8146c99f>] vc_resize+0x1f/0x30
       [<ffffffff813e4535>] fbcon_init+0x385/0x5a0
       [<ffffffff8146a4bc>] visual_init+0xbc/0x120
       [<ffffffff8146cd13>] do_bind_con_driver+0x163/0x320
       [<ffffffff8146cfa1>] do_take_over_console+0x61/0x70
       [<ffffffff813e2b93>] do_fbcon_takeover+0x63/0xc0
       [<ffffffff813e67a5>] fbcon_event_notify+0x715/0x820
       [<ffffffff81762f9d>] notifier_call_chain+0x5d/0x110
       [<ffffffff8107aadc>] __blocking_notifier_call_chain+0x6c/0xc0
       [<ffffffff8107ab46>] blocking_notifier_call_chain+0x16/0x20
       [<ffffffff813d7c0b>] fb_notifier_call_chain+0x1b/0x20
       [<ffffffff813d95b2>] register_framebuffer+0x1e2/0x320
       [<ffffffffa01043e1>] drm_fb_helper_initial_config+0x371/0x540 [drm_kms_helper]
       [<ffffffffa01bcb05>] nouveau_fbcon_init+0x105/0x140 [nouveau]
       [<ffffffffa01ad0af>] nouveau_drm_load+0x43f/0x610 [nouveau]
       [<ffffffffa008a79e>] drm_get_pci_dev+0x17e/0x2a0 [drm]
       [<ffffffffa01ad4da>] nouveau_drm_probe+0x25a/0x2a0 [nouveau]
       [<ffffffff813b13db>] local_pci_probe+0x4b/0x80
       [<ffffffff813b1701>] pci_device_probe+0x111/0x120
       [<ffffffff814977eb>] driver_probe_device+0x8b/0x3a0
       [<ffffffff81497bab>] __driver_attach+0xab/0xb0
       [<ffffffff814956ad>] bus_for_each_dev+0x5d/0xa0
       [<ffffffff814971fe>] driver_attach+0x1e/0x20
       [<ffffffff81496cc1>] bus_add_driver+0x111/0x290
       [<ffffffff814982b7>] driver_register+0x77/0x170
       [<ffffffff813b0454>] __pci_register_driver+0x64/0x70
       [<ffffffffa008a9da>] drm_pci_init+0x11a/0x130 [drm]
       [<ffffffffa022a04d>] nouveau_drm_init+0x4d/0x1000 [nouveau]
       [<ffffffff810002ea>] do_one_initcall+0xea/0x1a0
       [<ffffffff810c54cb>] load_module+0x123b/0x1bf0
       [<ffffffff810c5f57>] SyS_init_module+0xd7/0x120
       [<ffffffff817677c2>] system_call_fastpath+0x16/0x1b

other info that might help us debug this:

Chain exists of:
  &tty->termios_rwsem --> console_lock --> (fb_notifier_list).rwsem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock((fb_notifier_list).rwsem);
                               lock(console_lock);
                               lock((fb_notifier_list).rwsem);
  lock(&tty->termios_rwsem);

 *** DEADLOCK ***

7 locks held by modprobe/277:
 #0:  (&__lockdep_no_validate__){......}, at: [<ffffffff81497b5b>] __driver_attach+0x5b/0xb0
 #1:  (&__lockdep_no_validate__){......}, at: [<ffffffff81497b69>] __driver_attach+0x69/0xb0
 #2:  (drm_global_mutex){+.+.+.}, at: [<ffffffffa008a6dd>] drm_get_pci_dev+0xbd/0x2a0 [drm]
 #3:  (registration_lock){+.+.+.}, at: [<ffffffff813d93f5>] register_framebuffer+0x25/0x320
 #4:  (&fb_info->lock){+.+.+.}, at: [<ffffffff813d8116>] lock_fb_info+0x26/0x60
 #5:  (console_lock){+.+.+.}, at: [<ffffffff813d95a4>] register_framebuffer+0x1d4/0x320
 #6:  ((fb_notifier_list).rwsem){.+.+.+}, at: [<ffffffff8107aac6>] __blocking_notifier_call_chain+0x56/0xc0

stack backtrace:
CPU: 0 PID: 277 Comm: modprobe Not tainted 3.10.0-0+tip-xeon+lockdep #0+tip
Hardware name: Dell Inc. Precision WorkStation T5400  /0RW203, BIOS A11 04/30/2012
 ffffffff8213e5e0 ffff8802aa2fb298 ffffffff81755f19 ffff8802aa2fb2e8
 ffffffff8174f506 ffff8802aa2fa000 ffff8802aa2fb378 ffff8802aa2ea8e8
 ffff8802aa2ea910 ffff8802aa2ea8e8 0000000000000006 0000000000000007
Call Trace:
 [<ffffffff81755f19>] dump_stack+0x19/0x1b
 [<ffffffff8174f506>] print_circular_bug+0x1fb/0x20c
 [<ffffffff810b65c3>] __lock_acquire+0x1c43/0x1d30
 [<ffffffff810b775e>] ? mark_held_locks+0xae/0x120
 [<ffffffff810b78d5>] ? trace_hardirqs_on_caller+0x105/0x1d0
 [<ffffffff810b6d62>] lock_acquire+0x92/0x1f0
 [<ffffffff81452656>] ? tty_do_resize+0x36/0xe0
 [<ffffffff8175b724>] down_write+0x44/0x70
 [<ffffffff81452656>] ? tty_do_resize+0x36/0xe0
 [<ffffffff81452656>] tty_do_resize+0x36/0xe0
 [<ffffffff8146c841>] vc_do_resize+0x3e1/0x4c0
 [<ffffffff8146c99f>] vc_resize+0x1f/0x30
 [<ffffffff813e4535>] fbcon_init+0x385/0x5a0
 [<ffffffff8146a4bc>] visual_init+0xbc/0x120
 [<ffffffff8146cd13>] do_bind_con_driver+0x163/0x320
 [<ffffffff8146cfa1>] do_take_over_console+0x61/0x70
 [<ffffffff813e2b93>] do_fbcon_takeover+0x63/0xc0
 [<ffffffff813e67a5>] fbcon_event_notify+0x715/0x820
 [<ffffffff81762f9d>] notifier_call_chain+0x5d/0x110
 [<ffffffff8107aadc>] __blocking_notifier_call_chain+0x6c/0xc0
 [<ffffffff8107ab46>] blocking_notifier_call_chain+0x16/0x20
 [<ffffffff813d7c0b>] fb_notifier_call_chain+0x1b/0x20
 [<ffffffff813d95b2>] register_framebuffer+0x1e2/0x320
 [<ffffffffa01043e1>] drm_fb_helper_initial_config+0x371/0x540 [drm_kms_helper]
 [<ffffffff8173cbcb>] ? kmemleak_alloc+0x5b/0xc0
 [<ffffffff81198874>] ? kmem_cache_alloc_trace+0x104/0x290
 [<ffffffffa01035e1>] ? drm_fb_helper_single_add_all_connectors+0x81/0xf0 [drm_kms_helper]
 [<ffffffffa01bcb05>] nouveau_fbcon_init+0x105/0x140 [nouveau]
 [<ffffffffa01ad0af>] nouveau_drm_load+0x43f/0x610 [nouveau]
 [<ffffffffa008a79e>] drm_get_pci_dev+0x17e/0x2a0 [drm]
 [<ffffffffa01ad4da>] nouveau_drm_probe+0x25a/0x2a0 [nouveau]
 [<ffffffff8175f162>] ? _raw_spin_unlock_irqrestore+0x42/0x80
 [<ffffffff813b13db>] local_pci_probe+0x4b/0x80
 [<ffffffff813b1701>] pci_device_probe+0x111/0x120
 [<ffffffff814977eb>] driver_probe_device+0x8b/0x3a0
 [<ffffffff81497bab>] __driver_attach+0xab/0xb0
 [<ffffffff81497b00>] ? driver_probe_device+0x3a0/0x3a0
 [<ffffffff814956ad>] bus_for_each_dev+0x5d/0xa0
 [<ffffffff814971fe>] driver_attach+0x1e/0x20
 [<ffffffff81496cc1>] bus_add_driver+0x111/0x290
 [<ffffffffa022a000>] ? 0xffffffffa0229fff
 [<ffffffff814982b7>] driver_register+0x77/0x170
 [<ffffffffa022a000>] ? 0xffffffffa0229fff
 [<ffffffff813b0454>] __pci_register_driver+0x64/0x70
 [<ffffffffa008a9da>] drm_pci_init+0x11a/0x130 [drm]
 [<ffffffffa022a000>] ? 0xffffffffa0229fff
 [<ffffffffa022a000>] ? 0xffffffffa0229fff
 [<ffffffffa022a04d>] nouveau_drm_init+0x4d/0x1000 [nouveau]
 [<ffffffff810002ea>] do_one_initcall+0xea/0x1a0
 [<ffffffff810c54cb>] load_module+0x123b/0x1bf0
 [<ffffffff81399a50>] ? ddebug_proc_open+0xb0/0xb0
 [<ffffffff813855ae>] ? trace_hardirqs_on_thunk+0x3a/0x3f
 [<ffffffff810c5f57>] SyS_init_module+0xd7/0x120
 [<ffffffff817677c2>] system_call_fastpath+0x16/0x1b

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
We used to keep the port's char device structs and the /sys entries
around till the last reference to the port was dropped.  This is
actually unnecessary, and resulted in buggy behaviour:

1. Open port in guest
2. Hot-unplug port
3. Hot-plug a port with the same 'name' property as the unplugged one

This resulted in hot-plug being unsuccessful, as a port with the same
name already exists (even though it was unplugged).

This behaviour resulted in a warning message like this one:

-------------------8<---------------------------------------
WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xc9/0x130() (Not tainted)
Hardware name: KVM
sysfs: cannot create duplicate filename
'/devices/pci0000:00/0000:00:04.0/virtio0/virtio-ports/vport0p1'

Call Trace:
 [<ffffffff8106b607>] ? warn_slowpath_common+0x87/0xc0
 [<ffffffff8106b6f6>] ? warn_slowpath_fmt+0x46/0x50
 [<ffffffff811f2319>] ? sysfs_add_one+0xc9/0x130
 [<ffffffff811f23e8>] ? create_dir+0x68/0xb0
 [<ffffffff811f2469>] ? sysfs_create_dir+0x39/0x50
 [<ffffffff81273129>] ? kobject_add_internal+0xb9/0x260
 [<ffffffff812733d8>] ? kobject_add_varg+0x38/0x60
 [<ffffffff812734b4>] ? kobject_add+0x44/0x70
 [<ffffffff81349de4>] ? get_device_parent+0xf4/0x1d0
 [<ffffffff8134b389>] ? device_add+0xc9/0x650

-------------------8<---------------------------------------

Instead of relying on guest applications to release all references to
the ports, we should go ahead and unregister the port from all the core
layers.  Any open/read calls on the port will then just return errors,
and an unplug/plug operation on the host will succeed as expected.

This also caused buggy behaviour in case of the device removal (not just
a port): when the device was removed (which means all ports on that
device are removed automatically as well), the ports with active
users would clean up only when the last references were dropped -- and
it would be too late then to be referencing char device pointers,
resulting in oopses:

-------------------8<---------------------------------------
PID: 6162   TASK: ffff8801147ad500  CPU: 0   COMMAND: "cat"
 #0 [ffff88011b9d5a90] machine_kexec at ffffffff8103232b
 #1 [ffff88011b9d5af0] crash_kexec at ffffffff810b9322
 #2 [ffff88011b9d5bc0] oops_end at ffffffff814f4a50
 #3 [ffff88011b9d5bf0] die at ffffffff8100f26b
 #4 [ffff88011b9d5c20] do_general_protection at ffffffff814f45e2
 #5 [ffff88011b9d5c50] general_protection at ffffffff814f3db5
    [exception RIP: strlen+2]
    RIP: ffffffff81272ae2  RSP: ffff88011b9d5d00  RFLAGS: 00010246
    RAX: 0000000000000000  RBX: ffff880118901c18  RCX: 0000000000000000
    RDX: ffff88011799982c  RSI: 00000000000000d0  RDI: 3a303030302f3030
    RBP: ffff88011b9d5d38   R8: 0000000000000006   R9: ffffffffa0134500
    R10: 0000000000001000  R11: 0000000000001000  R12: ffff880117a1cc10
    R13: 00000000000000d0  R14: 0000000000000017  R15: ffffffff81aff700
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #6 [ffff88011b9d5d00] kobject_get_path at ffffffff8126dc5d
 #7 [ffff88011b9d5d40] kobject_uevent_env at ffffffff8126e551
 #8 [ffff88011b9d5dd0] kobject_uevent at ffffffff8126e9eb
 #9 [ffff88011b9d5de0] device_del at ffffffff813440c7

-------------------8<---------------------------------------

So clean up when we have all the context, and all that's left to do when
the references to the port have dropped is to free up the port struct
itself.

CC: <stable@vger.kernel.org>
Reported-by: chayang <chayang@redhat.com>
Reported-by: YOGANANTH SUBRAMANIAN <anantyog@in.ibm.com>
Reported-by: FuXiangChun <xfu@redhat.com>
Reported-by: Qunfang Zhang <qzhang@redhat.com>
Reported-by: Sibiao Luo <sluo@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
noglitch pushed a commit that referenced this pull request May 13, 2014
We met lockdep warning when enable and disable the bearer for commands such as:

tipc-config -netid=1234 -addr=1.1.3 -be=eth:eth0
tipc-config -netid=1234 -addr=1.1.3 -bd=eth:eth0

---------------------------------------------------

[  327.693595] ======================================================
[  327.693994] [ INFO: possible circular locking dependency detected ]
[  327.694519] 3.11.0-rc3-wwd-default #4 Tainted: G           O
[  327.694882] -------------------------------------------------------
[  327.695385] tipc-config/5825 is trying to acquire lock:
[  327.695754]  (((timer))#2){+.-...}, at: [<ffffffff8105be80>] del_timer_sync+0x0/0xd0
[  327.696018]
[  327.696018] but task is already holding lock:
[  327.696018]  (&(&b_ptr->lock)->rlock){+.-...}, at: [<ffffffffa02be58d>] bearer_disable+  0xdd/0x120 [tipc]
[  327.696018]
[  327.696018] which lock already depends on the new lock.
[  327.696018]
[  327.696018]
[  327.696018] the existing dependency chain (in reverse order) is:
[  327.696018]
[  327.696018] -> #1 (&(&b_ptr->lock)->rlock){+.-...}:
[  327.696018]        [<ffffffff810b3b4d>] validate_chain+0x6dd/0x870
[  327.696018]        [<ffffffff810b40bb>] __lock_acquire+0x3db/0x670
[  327.696018]        [<ffffffff810b4453>] lock_acquire+0x103/0x130
[  327.696018]        [<ffffffff814d65b1>] _raw_spin_lock_bh+0x41/0x80
[  327.696018]        [<ffffffffa02c5d48>] disc_timeout+0x18/0xd0 [tipc]
[  327.696018]        [<ffffffff8105b92a>] call_timer_fn+0xda/0x1e0
[  327.696018]        [<ffffffff8105bcd7>] run_timer_softirq+0x2a7/0x2d0
[  327.696018]        [<ffffffff8105379a>] __do_softirq+0x16a/0x2e0
[  327.696018]        [<ffffffff81053a35>] irq_exit+0xd5/0xe0
[  327.696018]        [<ffffffff81033005>] smp_apic_timer_interrupt+0x45/0x60
[  327.696018]        [<ffffffff814df4af>] apic_timer_interrupt+0x6f/0x80
[  327.696018]        [<ffffffff8100b70e>] arch_cpu_idle+0x1e/0x30
[  327.696018]        [<ffffffff810a039d>] cpu_idle_loop+0x1fd/0x280
[  327.696018]        [<ffffffff810a043e>] cpu_startup_entry+0x1e/0x20
[  327.696018]        [<ffffffff81031589>] start_secondary+0x89/0x90
[  327.696018]
[  327.696018] -> #0 (((timer))#2){+.-...}:
[  327.696018]        [<ffffffff810b33fe>] check_prev_add+0x43e/0x4b0
[  327.696018]        [<ffffffff810b3b4d>] validate_chain+0x6dd/0x870
[  327.696018]        [<ffffffff810b40bb>] __lock_acquire+0x3db/0x670
[  327.696018]        [<ffffffff810b4453>] lock_acquire+0x103/0x130
[  327.696018]        [<ffffffff8105bebd>] del_timer_sync+0x3d/0xd0
[  327.696018]        [<ffffffffa02c5855>] tipc_disc_delete+0x15/0x30 [tipc]
[  327.696018]        [<ffffffffa02be59f>] bearer_disable+0xef/0x120 [tipc]
[  327.696018]        [<ffffffffa02be74f>] tipc_disable_bearer+0x2f/0x60 [tipc]
[  327.696018]        [<ffffffffa02bfb32>] tipc_cfg_do_cmd+0x2e2/0x550 [tipc]
[  327.696018]        [<ffffffffa02c8c79>] handle_cmd+0x49/0xe0 [tipc]
[  327.696018]        [<ffffffff8143e898>] genl_family_rcv_msg+0x268/0x340
[  327.696018]        [<ffffffff8143ed30>] genl_rcv_msg+0x70/0xd0
[  327.696018]        [<ffffffff8143d4c9>] netlink_rcv_skb+0x89/0xb0
[  327.696018]        [<ffffffff8143e617>] genl_rcv+0x27/0x40
[  327.696018]        [<ffffffff8143d21e>] netlink_unicast+0x15e/0x1b0
[  327.696018]        [<ffffffff8143ddcf>] netlink_sendmsg+0x22f/0x400
[  327.696018]        [<ffffffff813f7836>] __sock_sendmsg+0x66/0x80
[  327.696018]        [<ffffffff813f7957>] sock_aio_write+0x107/0x120
[  327.696018]        [<ffffffff8117f76d>] do_sync_write+0x7d/0xc0
[  327.696018]        [<ffffffff8117fc56>] vfs_write+0x186/0x190
[  327.696018]        [<ffffffff811803e0>] SyS_write+0x60/0xb0
[  327.696018]        [<ffffffff814de852>] system_call_fastpath+0x16/0x1b
[  327.696018]
[  327.696018] other info that might help us debug this:
[  327.696018]
[  327.696018]  Possible unsafe locking scenario:
[  327.696018]
[  327.696018]        CPU0                    CPU1
[  327.696018]        ----                    ----
[  327.696018]   lock(&(&b_ptr->lock)->rlock);
[  327.696018]                                lock(((timer))#2);
[  327.696018]                                lock(&(&b_ptr->lock)->rlock);
[  327.696018]   lock(((timer))#2);
[  327.696018]
[  327.696018]  *** DEADLOCK ***
[  327.696018]
[  327.696018] 5 locks held by tipc-config/5825:
[  327.696018]  #0:  (cb_lock){++++++}, at: [<ffffffff8143e608>] genl_rcv+0x18/0x40
[  327.696018]  #1:  (genl_mutex){+.+.+.}, at: [<ffffffff8143ed66>] genl_rcv_msg+0xa6/0xd0
[  327.696018]  #2:  (config_mutex){+.+.+.}, at: [<ffffffffa02bf889>] tipc_cfg_do_cmd+0x39/ 0x550 [tipc]
[  327.696018]  #3:  (tipc_net_lock){++.-..}, at: [<ffffffffa02be738>] tipc_disable_bearer+ 0x18/0x60 [tipc]
[  327.696018]  #4:  (&(&b_ptr->lock)->rlock){+.-...}, at: [<ffffffffa02be58d>]             bearer_disable+0xdd/0x120 [tipc]
[  327.696018]
[  327.696018] stack backtrace:
[  327.696018] CPU: 2 PID: 5825 Comm: tipc-config Tainted: G           O 3.11.0-rc3-wwd-    default #4
[  327.696018] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
[  327.696018]  00000000ffffffff ffff880037fa77a8 ffffffff814d03dd 0000000000000000
[  327.696018]  ffff880037fa7808 ffff880037fa77e8 ffffffff810b1c4f 0000000037fa77e8
[  327.696018]  ffff880037fa7808 ffff880037e4db40 0000000000000000 ffff880037e4e318
[  327.696018] Call Trace:
[  327.696018]  [<ffffffff814d03dd>] dump_stack+0x4d/0xa0
[  327.696018]  [<ffffffff810b1c4f>] print_circular_bug+0x10f/0x120
[  327.696018]  [<ffffffff810b33fe>] check_prev_add+0x43e/0x4b0
[  327.696018]  [<ffffffff810b3b4d>] validate_chain+0x6dd/0x870
[  327.696018]  [<ffffffff81087a28>] ? sched_clock_cpu+0xd8/0x110
[  327.696018]  [<ffffffff810b40bb>] __lock_acquire+0x3db/0x670
[  327.696018]  [<ffffffff810b4453>] lock_acquire+0x103/0x130
[  327.696018]  [<ffffffff8105be80>] ? try_to_del_timer_sync+0x70/0x70
[  327.696018]  [<ffffffff8105bebd>] del_timer_sync+0x3d/0xd0
[  327.696018]  [<ffffffff8105be80>] ? try_to_del_timer_sync+0x70/0x70
[  327.696018]  [<ffffffffa02c5855>] tipc_disc_delete+0x15/0x30 [tipc]
[  327.696018]  [<ffffffffa02be59f>] bearer_disable+0xef/0x120 [tipc]
[  327.696018]  [<ffffffffa02be74f>] tipc_disable_bearer+0x2f/0x60 [tipc]
[  327.696018]  [<ffffffffa02bfb32>] tipc_cfg_do_cmd+0x2e2/0x550 [tipc]
[  327.696018]  [<ffffffff81218783>] ? security_capable+0x13/0x20
[  327.696018]  [<ffffffffa02c8c79>] handle_cmd+0x49/0xe0 [tipc]
[  327.696018]  [<ffffffff8143e898>] genl_family_rcv_msg+0x268/0x340
[  327.696018]  [<ffffffff8143ed30>] genl_rcv_msg+0x70/0xd0
[  327.696018]  [<ffffffff8143ecc0>] ? genl_lock+0x20/0x20
[  327.696018]  [<ffffffff8143d4c9>] netlink_rcv_skb+0x89/0xb0
[  327.696018]  [<ffffffff8143e608>] ? genl_rcv+0x18/0x40
[  327.696018]  [<ffffffff8143e617>] genl_rcv+0x27/0x40
[  327.696018]  [<ffffffff8143d21e>] netlink_unicast+0x15e/0x1b0
[  327.696018]  [<ffffffff81289d7c>] ? memcpy_fromiovec+0x6c/0x90
[  327.696018]  [<ffffffff8143ddcf>] netlink_sendmsg+0x22f/0x400
[  327.696018]  [<ffffffff813f7836>] __sock_sendmsg+0x66/0x80
[  327.696018]  [<ffffffff813f7957>] sock_aio_write+0x107/0x120
[  327.696018]  [<ffffffff813fe29c>] ? release_sock+0x8c/0xa0
[  327.696018]  [<ffffffff8117f76d>] do_sync_write+0x7d/0xc0
[  327.696018]  [<ffffffff8117fa24>] ? rw_verify_area+0x54/0x100
[  327.696018]  [<ffffffff8117fc56>] vfs_write+0x186/0x190
[  327.696018]  [<ffffffff811803e0>] SyS_write+0x60/0xb0
[  327.696018]  [<ffffffff814de852>] system_call_fastpath+0x16/0x1b

-----------------------------------------------------------------------

The problem is that the tipc_link_delete() will cancel the timer disc_timeout() when
the b_ptr->lock is hold, but the disc_timeout() still call b_ptr->lock to finish the
work, so the dead lock occurs.

We should unlock the b_ptr->lock when del the disc_timeout().

Remove link_timeout() still met the same problem, the patch:

http://article.gmane.org/gmane.network.tipc.general/4380

fix the problem, so no need to send patch for fix link_timeout() deadlock warming.

Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
noglitch pushed a commit that referenced this pull request May 13, 2014
With the introduction of PCI it became apparent that s390 should
convert to generic hardirqs as too many drivers do not have the
correct dependency for GENERIC_HARDIRQS. On the architecture
level s390 does not have irq lines. It has external interrupts,
I/O interrupts and adapter interrupts. This patch hard-codes all
external interrupts as irq #1, all I/O interrupts as irq #2 and
all adapter interrupts as irq #3. The additional information from
the lowcore associated with the interrupt is stored in the
pt_regs of the interrupt frame, where the interrupt handler can
pick it up. For PCI/MSI interrupts the adapter interrupt handler
scans the relevant bit fields and calls generic_handle_irq with
the virtual irq number for the MSI interrupt.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
Generally request_irq() should be called after hardware has been
initialized into a sane state.  However, sdhci driver currently calls
request_irq() before sdhci_init().  At least, the following kernel panic
seen on i.MX6 is caused by that.  The sdhci controller on i.MX6 may have
noisy glitch on DAT1 line, which will trigger SDIO interrupt handling
once request_irq() is called.  But at this point, the SDIO interrupt
handler host->sdio_irq_thread has not been registered yet.  Thus, we
see the NULL pointer access with wake_up_process(host->sdio_irq_thread)
in mmc_signal_sdio_irq().

Fix the panic by simply reverse the calling sequence between
request_irq() and sdhci_init().

sdhci-pltfm: SDHCI platform and OF driver helper
mmc0: no vqmmc regulator found
mmc0: no vmmc regulator found
Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = 80004000
[00000000] *pgd=00000000
Internal error: Oops: 5 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.0+ #3
task: 9f860000 ti: 9f862000 task.ti: 9f862000
PC is at wake_up_process+0xc/0x44
LR is at sdhci_irq+0x378/0x93c
pc : [<8004f768>]    lr : [<803fb698>]    psr: 40000193
sp : 9f863ba0  ip : 9f863bb8  fp : 9f863bb4
r10: 9f807900  r9 : 80761fbc  r8 : 00000000
r7 : 00000000  r6 : 00000000  r5 : 00000001  r4 : 9fa68000
r3 : 00000001  r2 : 00000002  r1 : 20000193  r0 : 00000000
Flags: nZcv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
Control: 10c53c7d  Table: 8000404a  DAC: 00000017
Process swapper/0 (pid: 1, stack limit = 0x9f862238)
Stack: (0x9f863ba0 to 0x9f864000)
3ba0: 00000001 9fa68000 9f863c04 9f863bb8 803fb698 8004f768 8011af00 80265aac
3bc0: 00000000 000003d9 00000000 9fa51880 00000001 00000000 9f863c14 9fa53640
3be0: 00000001 00000000 00000000 00000036 80761fbc 9f807900 9f863c3c 9f863c08
3c00: 80075154 803fb32c 802c2b38 802c63d8 802c63cc 9f807900 00000001 9f862000
3c20: 00000036 00000000 9f807930 60000113 9f863c54 9f863c40 800752ec 8007510c
3c40: 9f807900 00000001 9f863c6c 9f863c58 80078324 800752a8 00000036 8071fd64
3c60: 9f863c84 9f863c70 80074ac0 80078294 00000140 8072ab78 9f863cac 9f863c88
3c80: 8000ee34 80074aa4 00000000 a080e10c 8072acb 9f863cd0 a080e100 00000036
3ca0: 9f863ccc 9f863cb0 80008600 8000edec 805386a8 60000113 ffffffff 9f863d04
3cc0: 9f863d24 9f863cd0 8000e0c0 800085dc 9f807950 60000113 00000007 00000000
3ce0: 9f807900 9fa53640 9f807950 9fa68240 00000036 9f807930 60000113 9f863d24
3d00: 9f863d28 9f863d18 80076834 805386a8 60000113 ffffffff 9f863d64 9f863d28
3d20: 80076834 80538688 00000000 800bfe4c 00002fac 00000001 9f863d54 9fa53640
3d40: 9f807900 803fb320 9fa68240 00000080 00000000 00000036 9f863d94 9f863d68
3d60: 80076b38 80076674 00000080 9fa68240 9fa68000 04000000 9fa6836c 9fa6838
3d80: 806d620c 80700350 9f863dc4 9f863d98 803fce8c 80076a88 9fa532c0 9fa68240
3da0: 9fa51490 9fa51490 9fa68240 00000000 9f8ae600 9f81d080 9f863df4 9f863dc8
3dc0: 803fea0c 803fc808 9f863de4 9f863dd8 80125850 807b1ed8 807576b8 9f8ae610
3de0: 00000000 807576b8 9f863e04 9f863df8 802ee0d4 803fe798 9f863e2c 9f863e08
3e00: 802ecd1c 802ee0c0 00000000 9f8ae610 807576b8 9f8ae644 00000000 000000a9
3e20: 9f863e4c 9f863e30 802ecec0 802ecc30 9f83355c 807576b8 802ece2c 00000000
3e40: 9f863e74 9f863e50 802eb3d8 802ece38 9f83355c 9f8ac3b4 9f833570 807576b8
3e60: 80746e70 9fa51400 9f863e84 9f863e78 802ec838 802eb388 9f863eb4 9f863e88
3e80: 802ec3d0 802ec824 80692748 807620c0 9f863eb4 807576b8 00000006 807620c0
3ea0: 00000000 000000a9 9f863edc 9f863eb8 802ed3e8 802ec2fc 9f862000 00000006
3ec0: 807620c0 00000000 000000a9 80700350 9f863eec 9f863ee0 802ee2f8 802ed374
3ee0: 9f863efc 9f863ef0 80700364 802ee2b8 9f863f54 9f863f00 8000870c 8070035c
3f00: 9f863f54 9f863f10 9f862000 00000000 00000000 00000006 00000006 806d3aa4
3f20: 00000000 80688b18 9f863f54 80713560 00000006 80713540 807620c0 000000a9
3f40: 806d620c 8071ec24 9f863f94 9f863f58 806d6994 800086dc 00000006 00000006
3f60: 806d620c f6bfffff fb7f5df7 00000000 8052da28 00000000 00000000 00000000
3f80: 00000000 00000000 9f863fac 9f863f98 8052da38 806d689c ffffffff 00000000
3fa0: 00000000 9f863fb0 8000e5d8 8052da34 00000000 00000000 00000000 00000000
3fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
3fe0: 00000000 00000000 00000000 00000000 00000013 00000000 d9cdf5ff 1fff5ffe
Backtrace:
[<8004f75c>] (wake_up_process+0x0/0x44) from [<803fb698>] (sdhci_irq+0x378/0x93c)
 r4:9fa68000 r3:00000001
[<803fb320>] (sdhci_irq+0x0/0x93c) from [<80075154>] (handle_irq_event_percpu+0x54/0x19c)
[<80075100>] (handle_irq_event_percpu+0x0/0x19c) from [<800752ec>] (handle_irq_event+0x50/0x70)
[<8007529c>] (handle_irq_event+0x0/0x70) from [<80078324>] (handle_fasteoi_irq+0x9c/0x170)
 r5:00000001 r4:9f807900
[<80078288>] (handle_fasteoi_irq+0x0/0x170) from [<80074ac0>] (generic_handle_irq+0x28/0x38)
 r5:8071fd64 r4:00000036
[<80074a98>] (generic_handle_irq+0x0/0x38) from [<8000ee34>] (handle_IRQ+0x54/0xb4)
 r4:8072ab78 r3:00000140
[<8000ede0>] (handle_IRQ+0x0/0xb4) from [<80008600>] (gic_handle_irq+0x30/0x64)
 r8:00000036 r7:a080e100 r6:9f863cd0 r5:8072acbc r4:a080e10c
r3:00000000
[<800085d0>] (gic_handle_irq+0x0/0x64) from [<8000e0c0>] (__irq_svc+0x40/0x54)
Exception stack(0x9f863cd0 to 0x9f863d18)
3cc0:                                     9f807950 60000113 00000007 00000000
3ce0: 9f807900 9fa53640 9f807950 9fa68240 00000036 9f807930 60000113 9f863d24
3d00: 9f863d28 9f863d18 80076834 805386a8 60000113 ffffffff
 r7:9f863d04 r6:ffffffff r5:60000113 r4:805386a8
[<8053867c>] (_raw_spin_unlock_irqrestore+0x0/0x30) from [<80076834>] (__setup_irq+0x1cc/0x414)
[<80076668>] (__setup_irq+0x0/0x414) from [<80076b38>] (request_threaded_irq+0xbc/0x140)
[<80076a7c>] (request_threaded_irq+0x0/0x140) from [<803fce8c>] (sdhci_add_host+0x690/0xb88)
[<803fc7fc>] (sdhci_add_host+0x0/0xb88) from [<803fea0c>] (sdhci_esdhc_imx_probe+0x280/0x4d4)
 r8:9f81d080 r7:9f8ae600 r6:00000000 r5:9fa68240 r4:9fa51490
[<803fe78c>] (sdhci_esdhc_imx_probe+0x0/0x4d4) from [<802ee0d4>] (platform_drv_probe+0x20/0x24)
 r8:807576b8 r7:00000000 r6:9f8ae610 r5:807576b8 r4:807b1ed8
[<802ee0b4>] (platform_drv_probe+0x0/0x24) from [<802ecd1c>] (driver_probe_device+0xf8/0x208)
[<802ecc24>] (driver_probe_device+0x0/0x208) from [<802ecec0>] (__driver_attach+0x94/0x98)
 r8:000000a9 r7:00000000 r6:9f8ae644 r5:807576b8 r4:9f8ae610
r3:00000000
[<802ece2c>] (__driver_attach+0x0/0x98) from [<802eb3d8>] (bus_for_each_dev+0x5c/0x90)
 r6:00000000 r5:802ece2c r4:807576b8 r3:9f83355c
[<802eb37c>] (bus_for_each_dev+0x0/0x90) from [<802ec838>] (driver_attach+0x20/0x28)
 r6:9fa51400 r5:80746e70 r4:807576b8
[<802ec818>] (driver_attach+0x0/0x28) from [<802ec3d0>] (bus_add_driver+0xe0/0x234)
[<802ec2f0>] (bus_add_driver+0x0/0x234) from [<802ed3e8>] (driver_register+0x80/0x14c)
 r8:000000a9 r7:00000000 r6:807620c0 r5:00000006 r4:807576b8
[<802ed368>] (driver_register+0x0/0x14c) from [<802ee2f8>] (platform_driver_register+0x4c/0x60)
[<802ee2ac>] (platform_driver_register+0x0/0x60) from [<80700364>] (sdhci_esdhc_imx_driver_init+0x14/0x1c)
[<80700350>] (sdhci_esdhc_imx_driver_init+0x0/0x1c) from [<8000870c>] (do_one_initcall+0x3c/0x164)
[<800086d0>] (do_one_initcall+0x0/0x164) from [<806d6994>] (kernel_init_freeable+0x104/0x1d0)
[<806d6890>] (kernel_init_freeable+0x0/0x1d0) from [<8052da38>] (kernel_init+0x10/0xec)
[<8052da28>] (kernel_init+0x0/0xec) from [<8000e5d8>] (ret_from_fork+0x14/0x3c)
 r4:00000000 r3:ffffffff
Code: e89da800 e1a0c00d e92dd818 e24cb004 (e5903000)
---[ end trace e9af3588936b63f0 ]---
Kernel panic - not syncing: Fatal exception in interrupt

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
Some newer controllers support a fourth command buffer. This additional
command buffer allows to set an arbitrary length count, using the
NDCB3.NDLENCNT field, to perform non-standard length operations
such as the ONFI parameter page read.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Tested-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
When booting secondary CPUs, announce_cpu() is called to show which cpu has
been brought up. For example:

[    0.402751] smpboot: Booting Node   0, Processors  #1 #2 #3 #4 #5 OK
[    0.525667] smpboot: Booting Node   1, Processors  #6 #7 #8 #9 #10 #11 OK
[    0.755592] smpboot: Booting Node   0, Processors  #12 #13 #14 #15 #16 #17 OK
[    0.890495] smpboot: Booting Node   1, Processors  #18 #19 #20 #21 #22 #23

But the last "OK" is lost, because 'nr_cpu_ids-1' represents the maximum
possible cpu id. It should use the maximum present cpu id in case not all
CPUs booted up.

Signed-off-by: Libin <huawei.libin@huawei.com>
Cc: <guohanjun@huawei.com>
Cc: <wangyijing@huawei.com>
Cc: <fenghua.yu@intel.com>
Cc: <paul.gortmaker@windriver.com>
Link: http://lkml.kernel.org/r/1378378676-18276-1-git-send-email-huawei.libin@huawei.com
[ tweaked the changelog, removed unnecessary line break, tweaked the format to align the fields vertically. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
The way the page allocator interacts with kswapd creates aging imbalances,
where the amount of time a userspace page gets in memory under reclaim
pressure is dependent on which zone, which node the allocator took the
page frame from.

#1 fixes missed kswapd wakeups on NUMA systems, which lead to some
   nodes falling behind for a full reclaim cycle relative to the other
   nodes in the system

#3 fixes an interaction where kswapd and a continuous stream of page
   allocations keep the preferred zone of a task between the high and
   low watermark (allocations succeed + kswapd does not go to sleep)
   indefinitely, completely underutilizing the lower zones and
   thrashing on the preferred zone

These patches are the aging fairness part of the thrash-detection based
file LRU balancing.  Andrea recommended to submit them separately as they
are bugfixes in their own right.

The following test ran a foreground workload (memcachetest) with
background IO of various sizes on a 4 node 8G system (similar results were
observed with single-node 4G systems):

parallelio
                                               BAS                    FAIRALLO
                                              BASE                   FAIRALLOC
Ops memcachetest-0M              5170.00 (  0.00%)           5283.00 (  2.19%)
Ops memcachetest-791M            4740.00 (  0.00%)           5293.00 ( 11.67%)
Ops memcachetest-2639M           2551.00 (  0.00%)           4950.00 ( 94.04%)
Ops memcachetest-4487M           2606.00 (  0.00%)           3922.00 ( 50.50%)
Ops io-duration-0M                  0.00 (  0.00%)              0.00 (  0.00%)
Ops io-duration-791M               55.00 (  0.00%)             18.00 ( 67.27%)
Ops io-duration-2639M             235.00 (  0.00%)            103.00 ( 56.17%)
Ops io-duration-4487M             278.00 (  0.00%)            173.00 ( 37.77%)
Ops swaptotal-0M                    0.00 (  0.00%)              0.00 (  0.00%)
Ops swaptotal-791M             245184.00 (  0.00%)              0.00 (  0.00%)
Ops swaptotal-2639M            468069.00 (  0.00%)         108778.00 ( 76.76%)
Ops swaptotal-4487M            452529.00 (  0.00%)          76623.00 ( 83.07%)
Ops swapin-0M                       0.00 (  0.00%)              0.00 (  0.00%)
Ops swapin-791M                108297.00 (  0.00%)              0.00 (  0.00%)
Ops swapin-2639M               169537.00 (  0.00%)          50031.00 ( 70.49%)
Ops swapin-4487M               167435.00 (  0.00%)          34178.00 ( 79.59%)
Ops minorfaults-0M            1518666.00 (  0.00%)        1503993.00 (  0.97%)
Ops minorfaults-791M          1676963.00 (  0.00%)        1520115.00 (  9.35%)
Ops minorfaults-2639M         1606035.00 (  0.00%)        1799717.00 (-12.06%)
Ops minorfaults-4487M         1612118.00 (  0.00%)        1583825.00 (  1.76%)
Ops majorfaults-0M                  6.00 (  0.00%)              0.00 (  0.00%)
Ops majorfaults-791M            13836.00 (  0.00%)             10.00 ( 99.93%)
Ops majorfaults-2639M           22307.00 (  0.00%)           6490.00 ( 70.91%)
Ops majorfaults-4487M           21631.00 (  0.00%)           4380.00 ( 79.75%)

                 BAS    FAIRALLO
                BASE   FAIRALLOC
User          287.78      460.97
System       2151.67     3142.51
Elapsed      9737.00     8879.34

                                   BAS    FAIRALLO
                                  BASE   FAIRALLOC
Minor Faults                  53721925    57188551
Major Faults                    392195       15157
Swap Ins                       2994854      112770
Swap Outs                      4907092      134982
Direct pages scanned                 0       41824
Kswapd pages scanned          32975063     8128269
Kswapd pages reclaimed         6323069     7093495
Direct pages reclaimed               0       41824
Kswapd efficiency                  19%         87%
Kswapd velocity               3386.573     915.414
Direct efficiency                 100%        100%
Direct velocity                  0.000       4.710
Percentage direct scans             0%          0%
Zone normal velocity          2011.338     550.661
Zone dma32 velocity           1365.623     369.221
Zone dma velocity                9.612       0.242
Page writes by reclaim    18732404.000  614807.000
Page writes file              13825312      479825
Page writes anon               4907092      134982
Page reclaim immediate           85490        5647
Sector Reads                  12080532      483244
Sector Writes                 88740508    65438876
Page rescued immediate               0           0
Slabs scanned                    82560       12160
Direct inode steals                  0           0
Kswapd inode steals              24401       40013
Kswapd skipped wait                  0           0
THP fault alloc                      6           8
THP collapse alloc                5481        5812
THP splits                          75          22
THP fault fallback                   0           0
THP collapse fail                    0           0
Compaction stalls                    0          54
Compaction success                   0          45
Compaction failures                  0           9
Page migrate success            881492       82278
Page migrate failure                 0           0
Compaction pages isolated            0       60334
Compaction migrate scanned           0       53505
Compaction free scanned              0     1537605
Compaction cost                    914          86
NUMA PTE updates              46738231    41988419
NUMA hint faults              31175564    24213387
NUMA hint local faults        10427393     6411593
NUMA pages migrated             881492       55344
AutoNUMA cost                   156221      121361

The overall runtime was reduced, throughput for both the foreground
workload as well as the background IO improved, major faults, swapping and
reclaim activity shrunk significantly, reclaim efficiency more than
quadrupled.

This patch:

When the page allocator fails to get a page from all zones in its given
zonelist, it wakes up the per-node kswapds for all zones that are at their
low watermark.

However, with a system under load the free pages in a zone can fluctuate
enough that the allocation fails but the kswapd wakeup is also skipped
while the zone is still really close to the low watermark.

When one node misses a wakeup like this, it won't be aged before all the
other node's zones are down to their low watermarks again.  And skipping a
full aging cycle is an obvious fairness problem.

Kswapd runs until the high watermarks are restored, so it should also be
woken when the high watermarks are not met.  This ages nodes more equally
and creates a safety margin for the page counter fluctuation.

By using zone_balanced(), it will now check, in addition to the watermark,
if compaction requires more order-0 pages to create a higher order page.

Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Paul Bolle <paul.bollee@gmail.com>
Tested-by: Zlatko Calusic <zcalusic@bitsync.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
Gerlando Falauto reported that when HRTICK is enabled, it is
possible to trigger system deadlocks. These were hard to
reproduce, as HRTICK has been broken in the past, but seemed
to be connected to the timekeeping_seq lock.

Since seqlock/seqcount's aren't supported w/ lockdep, I added
some extra spinlock based locking and triggered the following
lockdep output:

[   15.849182] ntpd/4062 is trying to acquire lock:
[   15.849765]  (&(&pool->lock)->rlock){..-...}, at: [<ffffffff810aa9b5>] __queue_work+0x145/0x480
[   15.850051]
[   15.850051] but task is already holding lock:
[   15.850051]  (timekeeper_lock){-.-.-.}, at: [<ffffffff810df6df>] do_adjtimex+0x7f/0x100

<snip>

[   15.850051] Chain exists of: &(&pool->lock)->rlock --> &p->pi_lock --> timekeeper_lock
[   15.850051]  Possible unsafe locking scenario:
[   15.850051]
[   15.850051]        CPU0                    CPU1
[   15.850051]        ----                    ----
[   15.850051]   lock(timekeeper_lock);
[   15.850051]                                lock(&p->pi_lock);
[   15.850051] lock(timekeeper_lock);
[   15.850051] lock(&(&pool->lock)->rlock);
[   15.850051]
[   15.850051]  *** DEADLOCK ***

The deadlock was introduced by 06c017f ("timekeeping:
Hold timekeepering locks in do_adjtimex and hardpps") in 3.10

This patch avoids this deadlock, by moving the call to
schedule_delayed_work() outside of the timekeeper lock
critical section.

Reported-by: Gerlando Falauto <gerlando.falauto@keymile.com>
Tested-by: Lin Ming <minggr@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: stable <stable@vger.kernel.org> #3.11, 3.10
Link: http://lkml.kernel.org/r/1378943457-27314-1-git-send-email-john.stultz@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
Commit 05b016e "ARC: Setup Vector Table Base in early boot" moved
the Interrupt vector Table setup out of arc_init_IRQ() which is called
for all CPUs, to entry point of boot cpu only, breaking booting of others.

Fix by adding the same to entry point of non-boot CPUs too.

read_arc_build_cfg_regs() printing IVT Base Register didn't help the
casue since it prints a synthetic value if zero which is totally bogus,
so fix that to print the exact Register.

[vgupta: Remove the now stale comment from header of arc_init_IRQ and
also added the commentary for halt-on-reset]

Cc: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Cc: <stable@vger.kernel.org> #3.11
Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
Not all I/O ASIC versions have the free-running counter implemented, an
early revision used in the 5000/1xx models aka 3MIN and 4MIN did not have
it.  Therefore we cannot unconditionally use it as a clock source.
Fortunately if not implemented its register slot has a fixed value so it
is enough if we check for the value at the end of the calibration period
being the same as at the beginning.

This also means we need to look for another high-precision clock source on
the systems affected.  The 5000/1xx can have an R4000SC processor
installed where the CP0 Count register can be used as a clock source.
Unfortunately all the R4k DECstations suffer from the missed timer
interrupt on CP0 Count reads erratum, so we cannot use the CP0 timer as a
clock source and a clock event both at a time.  However we never need an
R4k clock event device because all DECstations have a DS1287A RTC chip
whose periodic interrupt can be used as a clock source.

This gives us the following four configuration possibilities for I/O ASIC
DECstations:

1. No I/O ASIC counter and no CP0 timer, e.g. R3k 5000/1xx (3MIN).

2. No I/O ASIC counter but the CP0 timer, i.e. R4k 5000/150 (4MIN).

3. The I/O ASIC counter but no CP0 timer, e.g. R3k 5000/240 (3MAX+).

4. The I/O ASIC counter and the CP0 timer, e.g. R4k 5000/260 (4MAX+).

For #1 and #2 this change stops the I/O ASIC free-running counter from
being installed as a clock source of a 0Hz frequency.  For #2 it also
arranges for the CP0 timer to be used as a clock source rather than a
clock event device, because having an accurate wall clock is more
important than a high-precision interval timer.  For #3 there is no
change.  For #4 the change makes the I/O ASIC free-running counter
installed as a clock source so that the CP0 timer can be used as a clock
event device.

Unfortunately the use of the CP0 timer as a clock event device relies on a
succesful completion of c0_compare_interrupt.  That never happens, because
while waiting for a CP0 Compare interrupt to happen the function spins in
a loop reading the CP0 Count register.  This makes the CP0 Count erratum
trigger reliably causing the interrupt waited for to be lost in all cases.
As a result #4 resorts to using the CP0 timer as a clock source as well,
just as #2.  However we want to keep this separate arrangement in case
(hope) c0_compare_interrupt is eventually rewritten such that it avoids
the erratum.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5825/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
This driver must validate the availability of the HID output report and
its size before it can write LED states via buzz_set_leds(). This stops
a heap overflow that is possible if a device provides a malicious HID
output report:

[  108.171280] usb 1-1: New USB device found, idVendor=054c, idProduct=0002
...
[  117.507877] BUG kmalloc-192 (Not tainted): Redzone overwritten

CVE-2013-2890

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org #3.11
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
noglitch pushed a commit that referenced this pull request May 13, 2014
When parsing lines from objdump a line containing source code starting
with a numeric label is mistaken for a line of disassembly starting with
a memory address.

Current validation fails to recognise that the "memory address" is out
of range and calculates an invalid offset which later causes this
segfault:

Program received signal SIGSEGV, Segmentation fault.
0x0000000000457315 in disasm__calc_percent (notes=0xc98970, evidx=0, offset=143705, end=2127526177, path=0x7fffffffbf50)
    at util/annotate.c:631
631				hits += h->addr[offset++];
(gdb) bt
 #0  0x0000000000457315 in disasm__calc_percent (notes=0xc98970, evidx=0, offset=143705, end=2127526177, path=0x7fffffffbf50)
    at util/annotate.c:631
 #1  0x00000000004d65e3 in annotate_browser__calc_percent (browser=0x7fffffffd130, evsel=0xa01da0) at ui/browsers/annotate.c:364
 #2  0x00000000004d7433 in annotate_browser__run (browser=0x7fffffffd130, evsel=0xa01da0, hbt=0x0) at ui/browsers/annotate.c:672
 #3  0x00000000004d80c9 in symbol__tui_annotate (sym=0xc989a0, map=0xa02660, evsel=0xa01da0, hbt=0x0) at ui/browsers/annotate.c:962
 #4  0x00000000004d7aa0 in hist_entry__tui_annotate (he=0xdf73f0, evsel=0xa01da0, hbt=0x0) at ui/browsers/annotate.c:823
 #5  0x00000000004dd648 in perf_evsel__hists_browse (evsel=0xa01da0, nr_events=1, helpline=
    0x58b768 "For a higher level overview, try: perf report --sort comm,dso", ev_name=0xa02cd0 "cycles", left_exits=false, hbt=
    0x0, min_pcnt=0, env=0xa011e0) at ui/browsers/hists.c:1659
 #6  0x00000000004de372 in perf_evlist__tui_browse_hists (evlist=0xa01520, help=
    0x58b768 "For a higher level overview, try: perf report --sort comm,dso", hbt=0x0, min_pcnt=0, env=0xa011e0)
    at ui/browsers/hists.c:1950
 #7  0x000000000042cf6b in __cmd_report (rep=0x7fffffffd6c0) at builtin-report.c:581
 #8  0x000000000042e25d in cmd_report (argc=0, argv=0x7fffffffe4b0, prefix=0x0) at builtin-report.c:965
 #9  0x000000000041a0e1 in run_builtin (p=0x801548, argc=1, argv=0x7fffffffe4b0) at perf.c:319
 #10 0x000000000041a319 in handle_internal_command (argc=1, argv=0x7fffffffe4b0) at perf.c:376
 #11 0x000000000041a465 in run_argv (argcp=0x7fffffffe38c, argv=0x7fffffffe380) at perf.c:420
 #12 0x000000000041a707 in main (argc=1, argv=0x7fffffffe4b0) at perf.c:521

After the fix is applied the symbol can be annotated showing the
problematic line "1:      rep"

copy_user_generic_string  /usr/lib/debug/lib/modules/3.9.10-100.fc17.x86_64/vmlinux
             */
            ENTRY(copy_user_generic_string)
                    CFI_STARTPROC
                    ASM_STAC
                    andl %edx,%edx
              and    %edx,%edx
                    jz 4f
              je     37
                    cmpl $8,%edx
              cmp    $0x8,%edx
                    jb 2f           /* less than 8 bytes, go to byte copy loop */
              jb     33
                    ALIGN_DESTINATION
              mov    %edi,%ecx
              and    $0x7,%ecx
              je     28
              sub    $0x8,%ecx
              neg    %ecx
              sub    %ecx,%edx
        1a:   mov    (%rsi),%al
              mov    %al,(%rdi)
              inc    %rsi
              inc    %rdi
              dec    %ecx
              jne    1a
                    movl %edx,%ecx
        28:   mov    %edx,%ecx
                    shrl $3,%ecx
              shr    $0x3,%ecx
                    andl $7,%edx
              and    $0x7,%edx
            1:      rep
100.00        rep    movsq %ds:(%rsi),%es:(%rdi)
                    movsq
            2:      movl %edx,%ecx
        33:   mov    %edx,%ecx
            3:      rep
              rep    movsb %ds:(%rsi),%es:(%rdi)
                    movsb
            4:      xorl %eax,%eax
        37:   xor    %eax,%eax
              data32 xchg %ax,%ax
                    ASM_CLAC
                    ret
              retq

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1379009721-27667-1-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
Fedora Ruby maintainer reported latest Ruby doesn't work on Fedora Rawhide
on ARM. (http://bugs.ruby-lang.org/issues/9008)

Because of, commit 1c6b39a (alarmtimers: Return -ENOTSUPP if no
RTC device is present) intruduced to return ENOTSUPP when
clock_get{time,res} can't find a RTC device. However this is incorrect.

First, ENOTSUPP isn't exported to userland (ENOTSUP or EOPNOTSUP are the
closest userland equivlents).

Second, Posix and Linux man pages agree that clock_gettime and
clock_getres should return EINVAL if clk_id argument is invalid.
While the arugment that the clockid is valid, but just not supported
on this hardware could be made, this is just a technicality that
doesn't help userspace applicaitons, and only complicates error
handling.

Thus, this patch changes the code to use EINVAL.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: stable <stable@vger.kernel.org>  #3.0 and up
Reported-by: Vit Ondruch <v.ondruch@tiscali.cz>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
[jstultz: Tweaks to commit message to include full rational]
Signed-off-by: John Stultz <john.stultz@linaro.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
Andrey reported the following report:

ERROR: AddressSanitizer: heap-buffer-overflow on address ffff8800359c99f3
ffff8800359c99f3 is located 0 bytes to the right of 243-byte region [ffff8800359c9900, ffff8800359c99f3)
Accessed by thread T13003:
  #0 ffffffff810dd2da (asan_report_error+0x32a/0x440)
  #1 ffffffff810dc6b0 (asan_check_region+0x30/0x40)
  #2 ffffffff810dd4d3 (__tsan_write1+0x13/0x20)
  #3 ffffffff811cd19e (ftrace_regex_release+0x1be/0x260)
  #4 ffffffff812a1065 (__fput+0x155/0x360)
  #5 ffffffff812a12de (____fput+0x1e/0x30)
  #6 ffffffff8111708d (task_work_run+0x10d/0x140)
  #7 ffffffff810ea043 (do_exit+0x433/0x11f0)
  #8 ffffffff810eaee4 (do_group_exit+0x84/0x130)
  #9 ffffffff810eafb1 (SyS_exit_group+0x21/0x30)
  #10 ffffffff81928782 (system_call_fastpath+0x16/0x1b)

Allocated by thread T5167:
  #0 ffffffff810dc778 (asan_slab_alloc+0x48/0xc0)
  #1 ffffffff8128337c (__kmalloc+0xbc/0x500)
  #2 ffffffff811d9d54 (trace_parser_get_init+0x34/0x90)
  #3 ffffffff811cd7b3 (ftrace_regex_open+0x83/0x2e0)
  #4 ffffffff811cda7d (ftrace_filter_open+0x2d/0x40)
  #5 ffffffff8129b4ff (do_dentry_open+0x32f/0x430)
  #6 ffffffff8129b668 (finish_open+0x68/0xa0)
  #7 ffffffff812b66ac (do_last+0xb8c/0x1710)
  #8 ffffffff812b7350 (path_openat+0x120/0xb50)
  #9 ffffffff812b8884 (do_filp_open+0x54/0xb0)
  #10 ffffffff8129d36c (do_sys_open+0x1ac/0x2c0)
  #11 ffffffff8129d4b7 (SyS_open+0x37/0x50)
  #12 ffffffff81928782 (system_call_fastpath+0x16/0x1b)

Shadow bytes around the buggy address:
  ffff8800359c9700: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
  ffff8800359c9780: fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa
  ffff8800359c9800: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  ffff8800359c9880: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  ffff8800359c9900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>ffff8800359c9980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00[03]fb
  ffff8800359c9a00: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  ffff8800359c9a80: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  ffff8800359c9b00: fa fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00
  ffff8800359c9b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ffff8800359c9c00: 00 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07
  Heap redzone:          fa
  Heap kmalloc redzone:  fb
  Freed heap region:     fd
  Shadow gap:            fe

The out-of-bounds access happens on 'parser->buffer[parser->idx] = 0;'

Although the crash happened in ftrace_regex_open() the real bug
occurred in trace_get_user() where there's an incrementation to
parser->idx without a check against the size. The way it is triggered
is if userspace sends in 128 characters (EVENT_BUF_SIZE + 1), the loop
that reads the last character stores it and then breaks out because
there is no more characters. Then the last character is read to determine
what to do next, and the index is incremented without checking size.

Then the caller of trace_get_user() usually nulls out the last character
with a zero, but since the index is equal to the size, it writes a nul
character after the allocated space, which can corrupt memory.

Luckily, only root user has write access to this file.

Link: http://lkml.kernel.org/r/20131009222323.04fd1a0d@gandalf.local.home

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
…pacing

When interrupt pacing is enabled, receive/transmit statistics are not
updated properly by hardware which leads to ISR return with IRQ_NONE
and inturn kernel disables the interrupt. This patch removed the checking
of receive/transmit statistics from ISR.

This patch is verified with AM335x Beagle Bone Black and below is the
kernel warn when interrupt pacing is enabled.

[  104.298254] irq 58: nobody cared (try booting with the "irqpoll" option)
[  104.305356] CPU: 0 PID: 1073 Comm: iperf Not tainted 3.12.0-rc3-00342-g77d4015 #3
[  104.313284] [<c001bb84>] (unwind_backtrace+0x0/0xf0) from [<c0017db0>] (show_stack+0x10/0x14)
[  104.322282] [<c0017db0>] (show_stack+0x10/0x14) from [<c0507920>] (dump_stack+0x78/0x94)
[  104.330816] [<c0507920>] (dump_stack+0x78/0x94) from [<c0088c1c>] (__report_bad_irq+0x20/0xc0)
[  104.339889] [<c0088c1c>] (__report_bad_irq+0x20/0xc0) from [<c008912c>] (note_interrupt+0x1dc/0x23c)
[  104.349505] [<c008912c>] (note_interrupt+0x1dc/0x23c) from [<c0086d74>] (handle_irq_event_percpu+0xc4/0x238)
[  104.359851] [<c0086d74>] (handle_irq_event_percpu+0xc4/0x238) from [<c0086f24>] (handle_irq_event+0x3c/0x5c)
[  104.370198] [<c0086f24>] (handle_irq_event+0x3c/0x5c) from [<c008991c>] (handle_level_irq+0xac/0x10c)
[  104.379907] [<c008991c>] (handle_level_irq+0xac/0x10c) from [<c00866d8>] (generic_handle_irq+0x20/0x30)
[  104.389812] [<c00866d8>] (generic_handle_irq+0x20/0x30) from [<c0014ce8>] (handle_IRQ+0x4c/0xb0)
[  104.399066] [<c0014ce8>] (handle_IRQ+0x4c/0xb0) from [<c000856c>] (omap3_intc_handle_irq+0x60/0x74)
[  104.408598] [<c000856c>] (omap3_intc_handle_irq+0x60/0x74) from [<c050d8e4>] (__irq_svc+0x44/0x5c)
[  104.418021] Exception stack(0xde4f7c00 to 0xde4f7c48)
[  104.423345] 7c00: 00000001 00000000 00000000 dd002140 60000013 de006e54 00000002 00000000
[  104.431952] 7c20: de345748 00000040 c11c8588 00018ee0 00000000 de4f7c48 c009dfc8 c050d300
[  104.440553] 7c40: 60000013 ffffffff
[  104.444237] [<c050d8e4>] (__irq_svc+0x44/0x5c) from [<c050d300>] (_raw_spin_unlock_irqrestore+0x34/0x44)
[  104.454220] [<c050d300>] (_raw_spin_unlock_irqrestore+0x34/0x44) from [<c00868c0>] (__irq_put_desc_unlock+0x14/0x38)
[  104.465295] [<c00868c0>] (__irq_put_desc_unlock+0x14/0x38) from [<c0088068>] (enable_irq+0x4c/0x74)
[  104.474829] [<c0088068>] (enable_irq+0x4c/0x74) from [<c03abd24>] (cpsw_poll+0xb8/0xdc)
[  104.483276] [<c03abd24>] (cpsw_poll+0xb8/0xdc) from [<c044ef68>] (net_rx_action+0xc0/0x1e8)
[  104.492085] [<c044ef68>] (net_rx_action+0xc0/0x1e8) from [<c0048a90>] (__do_softirq+0x100/0x27c)
[  104.501338] [<c0048a90>] (__do_softirq+0x100/0x27c) from [<c0048cd0>] (do_softirq+0x68/0x70)
[  104.510224] [<c0048cd0>] (do_softirq+0x68/0x70) from [<c0048e8c>] (local_bh_enable+0xd0/0xe4)
[  104.519211] [<c0048e8c>] (local_bh_enable+0xd0/0xe4) from [<c048c774>] (tcp_rcv_established+0x450/0x648)
[  104.529201] [<c048c774>] (tcp_rcv_established+0x450/0x648) from [<c0494904>] (tcp_v4_do_rcv+0x154/0x474)
[  104.539195] [<c0494904>] (tcp_v4_do_rcv+0x154/0x474) from [<c043d750>] (release_sock+0xac/0x1ac)
[  104.548448] [<c043d750>] (release_sock+0xac/0x1ac) from [<c04844e8>] (tcp_recvmsg+0x4d0/0xa8c)
[  104.557528] [<c04844e8>] (tcp_recvmsg+0x4d0/0xa8c) from [<c04a8720>] (inet_recvmsg+0xcc/0xf0)
[  104.566507] [<c04a8720>] (inet_recvmsg+0xcc/0xf0) from [<c0439744>] (sock_recvmsg+0x90/0xb0)
[  104.575394] [<c0439744>] (sock_recvmsg+0x90/0xb0) from [<c043b778>] (SyS_recvfrom+0x88/0xd8)
[  104.584280] [<c043b778>] (SyS_recvfrom+0x88/0xd8) from [<c043b7e0>] (sys_recv+0x18/0x20)
[  104.592805] [<c043b7e0>] (sys_recv+0x18/0x20) from [<c0013da0>] (ret_fast_syscall+0x0/0x48)
[  104.601587] handlers:
[  104.603992] [<c03acd94>] cpsw_interrupt
[  104.608040] Disabling IRQ #58

Cc: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
noglitch pushed a commit that referenced this pull request May 13, 2014
_nfs4_opendata_reclaim_to_nfs4_state doesn't expect to see a cached
open CLAIM_PREVIOUS, but this can happen. An example is when there are
RDWR openers and RDONLY openers on a delegation stateid. The recovery
path will first try an open CLAIM_PREVIOUS for the RDWR openers, this
marks the delegation as not needing RECLAIM anymore, so the open
CLAIM_PREVIOUS for the RDONLY openers will not actually send an rpc.

The NULL dereference is due to _nfs4_opendata_reclaim_to_nfs4_state
returning PTR_ERR(rpc_status) when !rpc_done. When the open is
cached, rpc_done == 0 and rpc_status == 0, thus
_nfs4_opendata_reclaim_to_nfs4_state returns NULL - this is unexpected
by callers of nfs4_opendata_to_nfs4_state().

This can be reproduced easily by opening the same file two times on an
NFSv4.0 mount with delegations enabled, once as RDWR and once as RDONLY then
sleeping for a long time.  While the files are held open, kick off state
recovery and this NULL dereference will be hit every time.

An example OOPS:

[   65.003602] BUG: unable to handle kernel NULL pointer dereference at 00000000
00000030
[   65.005312] IP: [<ffffffffa037d6ee>] __nfs4_close+0x1e/0x160 [nfsv4]
[   65.006820] PGD 7b0ea067 PUD 791ff067 PMD 0
[   65.008075] Oops: 0000 [#1] SMP
[   65.008802] Modules linked in: rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache
snd_ens1371 gameport nfsd snd_rawmidi snd_ac97_codec ac97_bus btusb snd_seq snd
_seq_device snd_pcm ppdev bluetooth auth_rpcgss coretemp snd_page_alloc crc32_pc
lmul crc32c_intel ghash_clmulni_intel microcode rfkill nfs_acl vmw_balloon serio
_raw snd_timer lockd parport_pc e1000 snd soundcore parport i2c_piix4 shpchp vmw
_vmci sunrpc ata_generic mperf pata_acpi mptspi vmwgfx ttm scsi_transport_spi dr
m mptscsih mptbase i2c_core
[   65.018684] CPU: 0 PID: 473 Comm: 192.168.10.85-m Not tainted 3.11.2-201.fc19
.x86_64 #1
[   65.020113] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop
Reference Platform, BIOS 6.00 07/31/2013
[   65.022012] task: ffff88003707e320 ti: ffff88007b906000 task.ti: ffff88007b906000
[   65.023414] RIP: 0010:[<ffffffffa037d6ee>]  [<ffffffffa037d6ee>] __nfs4_close+0x1e/0x160 [nfsv4]
[   65.025079] RSP: 0018:ffff88007b907d10  EFLAGS: 00010246
[   65.026042] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[   65.027321] RDX: 0000000000000050 RSI: 0000000000000001 RDI: 0000000000000000
[   65.028691] RBP: ffff88007b907d38 R08: 0000000000016f60 R09: 0000000000000000
[   65.029990] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
[   65.031295] R13: 0000000000000050 R14: 0000000000000000 R15: 0000000000000001
[   65.032527] FS:  0000000000000000(0000) GS:ffff88007f600000(0000) knlGS:0000000000000000
[   65.033981] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   65.035177] CR2: 0000000000000030 CR3: 000000007b27f000 CR4: 00000000000407f0
[   65.036568] Stack:
[   65.037011]  0000000000000000 0000000000000001 ffff88007b907d90 ffff88007a880220
[   65.038472]  ffff88007b768de8 ffff88007b907d48 ffffffffa037e4a5 ffff88007b907d80
[   65.039935]  ffffffffa036a6c8 ffff880037020e40 ffff88007a880000 ffff880037020e40
[   65.041468] Call Trace:
[   65.042050]  [<ffffffffa037e4a5>] nfs4_close_state+0x15/0x20 [nfsv4]
[   65.043209]  [<ffffffffa036a6c8>] nfs4_open_recover_helper+0x148/0x1f0 [nfsv4]
[   65.044529]  [<ffffffffa036a886>] nfs4_open_recover+0x116/0x150 [nfsv4]
[   65.045730]  [<ffffffffa036d98d>] nfs4_open_reclaim+0xad/0x150 [nfsv4]
[   65.046905]  [<ffffffffa037d979>] nfs4_do_reclaim+0x149/0x5f0 [nfsv4]
[   65.048071]  [<ffffffffa037e1dc>] nfs4_run_state_manager+0x3bc/0x670 [nfsv4]
[   65.049436]  [<ffffffffa037de20>] ? nfs4_do_reclaim+0x5f0/0x5f0 [nfsv4]
[   65.050686]  [<ffffffffa037de20>] ? nfs4_do_reclaim+0x5f0/0x5f0 [nfsv4]
[   65.051943]  [<ffffffff81088640>] kthread+0xc0/0xd0
[   65.052831]  [<ffffffff81088580>] ? insert_kthread_work+0x40/0x40
[   65.054697]  [<ffffffff8165686c>] ret_from_fork+0x7c/0xb0
[   65.056396]  [<ffffffff81088580>] ? insert_kthread_work+0x40/0x40
[   65.058208] Code: 5c 41 5d 5d c3 0f 1f 84 00 00 00 00 00 66 66 66 66 90 55 48 89 e5 41 57 41 89 f7 41 56 41 89 ce 41 55 41 89 d5 41 54 53 48 89 fb <4c> 8b 67 30 f0 41 ff 44 24 44 49 8d 7c 24 40 e8 0e 0a 2d e1 44
[   65.065225] RIP  [<ffffffffa037d6ee>] __nfs4_close+0x1e/0x160 [nfsv4]
[   65.067175]  RSP <ffff88007b907d10>
[   65.068570] CR2: 0000000000000030
[   65.070098] ---[ end trace 0d1fe4f5c7dd6f8b ]---

Cc: <stable@vger.kernel.org> #3.7+
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
I've seen a fair number of issues with kswapd and other processes
appearing to get stuck in v3.12-rc.  Using sysrq-p many times seems to
indicate that it gets stuck somewhere in list_lru_walk_node(), called
from prune_icache_sb() and super_cache_scan().

I never seem to be able to trigger a calltrace for functions above that
point.

So I decided to add the following to super_cache_scan():

    @@ -81,10 +81,14 @@ static unsigned long super_cache_scan(struct shrinker *shrink,
            inodes = list_lru_count_node(&sb->s_inode_lru, sc->nid);
            dentries = list_lru_count_node(&sb->s_dentry_lru, sc->nid);
            total_objects = dentries + inodes + fs_objects + 1;
    +printk("%s:%u: %s: dentries %lu inodes %lu total %lu\n", current->comm, current->pid, __func__, dentries, inodes, total_objects);

            /* proportion the scan between the caches */
            dentries = mult_frac(sc->nr_to_scan, dentries, total_objects);
            inodes = mult_frac(sc->nr_to_scan, inodes, total_objects);
    +printk("%s:%u: %s: dentries %lu inodes %lu\n", current->comm, current->pid, __func__, dentries, inodes);
    +BUG_ON(dentries == 0);
    +BUG_ON(inodes == 0);

            /*
             * prune the dcache first as the icache is pinned by it, then
    @@ -99,7 +103,7 @@ static unsigned long super_cache_scan(struct shrinker *shrink,
                    freed += sb->s_op->free_cached_objects(sb, fs_objects,
                                                           sc->nid);
            }
    -
    +printk("%s:%u: %s: dentries %lu inodes %lu freed %lu\n", current->comm, current->pid, __func__, dentries, inodes, freed);
            drop_super(sb);
            return freed;
     }

and shortly thereafter, having applied some pressure, I got this:

    update-apt-xapi:1616: super_cache_scan: dentries 25632 inodes 2 total 25635
    update-apt-xapi:1616: super_cache_scan: dentries 1023 inodes 0
    ------------[ cut here ]------------
    Kernel BUG at c0101994 [verbose debug info unavailable]
    Internal error: Oops - BUG: 0 [#3] SMP ARM
    Modules linked in: fuse rfcomm bnep bluetooth hid_cypress
    CPU: 0 PID: 1616 Comm: update-apt-xapi Tainted: G      D      3.12.0-rc7+ #154
    task: daea1200 ti: c3bf8000 task.ti: c3bf8000
    PC is at super_cache_scan+0x1c0/0x278
    LR is at trace_hardirqs_on+0x14/0x18
    Process update-apt-xapi (pid: 1616, stack limit = 0xc3bf8240)
    ...
    Backtrace:
      (super_cache_scan) from [<c00cd69c>] (shrink_slab+0x254/0x4c8)
      (shrink_slab) from [<c00d09a0>] (try_to_free_pages+0x3a0/0x5e0)
      (try_to_free_pages) from [<c00c59cc>] (__alloc_pages_nodemask+0x5)
      (__alloc_pages_nodemask) from [<c00e07c0>] (__pte_alloc+0x2c/0x13)
      (__pte_alloc) from [<c00e3a70>] (handle_mm_fault+0x84c/0x914)
      (handle_mm_fault) from [<c001a4cc>] (do_page_fault+0x1f0/0x3bc)
      (do_page_fault) from [<c001a7b0>] (do_translation_fault+0xac/0xb8)
      (do_translation_fault) from [<c000840c>] (do_DataAbort+0x38/0xa0)
      (do_DataAbort) from [<c00133f8>] (__dabt_usr+0x38/0x40)

Notice that we had a very low number of inodes, which were reduced to
zero my mult_frac().

Now, prune_icache_sb() calls list_lru_walk_node() passing that number of
inodes (0) into that as the number of objects to scan:

    long prune_icache_sb(struct super_block *sb, unsigned long nr_to_scan,
                         int nid)
    {
            LIST_HEAD(freeable);
            long freed;

            freed = list_lru_walk_node(&sb->s_inode_lru, nid, inode_lru_isolate,
                                           &freeable, &nr_to_scan);

which does:

    unsigned long
    list_lru_walk_node(struct list_lru *lru, int nid, list_lru_walk_cb isolate,
                       void *cb_arg, unsigned long *nr_to_walk)
    {

            struct list_lru_node    *nlru = &lru->node[nid];
            struct list_head *item, *n;
            unsigned long isolated = 0;

            spin_lock(&nlru->lock);
    restart:
            list_for_each_safe(item, n, &nlru->list) {
                    enum lru_status ret;

                    /*
                     * decrement nr_to_walk first so that we don't livelock if we
                     * get stuck on large numbesr of LRU_RETRY items
                     */
                    if (--(*nr_to_walk) == 0)
                            break;

So, if *nr_to_walk was zero when this function was entered, that means
we're wanting to operate on (~0UL)+1 objects - which might as well be
infinite.

Clearly this is not correct behaviour.  If we think about the behaviour
of this function when *nr_to_walk is 1, then clearly it's wrong - we
decrement first and then test for zero - which results in us doing
nothing at all.  A post-decrement would give the desired behaviour -
we'd try to walk one object and one object only if *nr_to_walk were one.

It also gives the correct behaviour for zero - we exit at this point.

Fixes: 5cedf72 ("list_lru: fix broken LRU_RETRY behaviour")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
[ Modified to make sure we never underflow the count: this function gets
  called in a loop, so the 0 -> ~0ul transition is dangerous  - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
A vmalloc fault needs to sync up PGD/PTE entry from init_mm to current
task's "active_mm".  ARC vmalloc fault handler however was using mm.

A vmalloc fault for non user task context (actually pre-userland, from
init thread's open for /dev/console) caused the handler to deref NULL mm
(for mm->pgd)

The reasons it worked so far is amazing:

1. By default (!SMP), vmalloc fault handler uses a cached value of PGD.
   In SMP that MMU register is repurposed hence need for mm pointer deref.

2. In pre-3.12 SMP kernel, the problem triggering vmalloc didn't exist in
   pre-userland code path - it was introduced with commit 20bafb3
   "n_tty: Move buffers into n_tty_data"

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Gilad Ben-Yossef <gilad@benyossef.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: stable@vger.kernel.org    #3.10 and 3.11
Cc: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
With Line length being constant now, we can fold the 2 helpers into 1.
This allows applying any optimizations (forthcoming) to single place.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
…/kernel/git/vgupta/arc

Pull ARC changes from Vineet Gupta:
 - Towards a working SMP setup (ASID allocation, TLB Flush,...)
 - Support for TRACE_IRQFLAGS, LOCKDEP
 - cacheflush backend consolidation for I/D
 - Lots of allmodconfig fixlets from Chen
 - Other improvements/fixes

* tag 'arc-v3.13-rc1-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (25 commits)
  ARC: [plat-arcfpga] defconfig update
  smp, ARC: kill SMP single function call interrupt
  ARC: [SMP] Disallow RTSC
  ARC: [SMP] Fix build failures for large NR_CPUS
  ARC: [SMP] enlarge possible NR_CPUS
  ARC: [SMP] TLB flush
  ARC: [SMP] ASID allocation
  arc: export symbol for pm_power_off in reset.c
  arc: export symbol for save_stack_trace() in stacktrace.c
  arc: remove '__init' for get_hw_config_num_irq()
  arc: remove '__init' for first_lines_of_secondary()
  arc: remove '__init' for setup_processor() and arc_init_IRQ()
  arc: kgdb: add default implementation for kgdb_roundup_cpus()
  ARC: Fix bogus gcc warning and micro-optimise TLB iteration loop
  ARC: Add support for irqflags tracing and lockdep
  ARC: Reset the value of Interrupt Priority Register
  ARC: Reduce #ifdef'ery for unaligned access emulation
  ARC: Change calling convention of do_page_fault()
  ARC: cacheflush optim - PTAG can be loop invariant if V-P is const
  ARC: cacheflush refactor #3: Unify the {d,i}cache flush leaf helpers
  ...
noglitch pushed a commit that referenced this pull request May 13, 2014
…ux/kernel/git/tip/tip

Pull x86 boot changes from Ingo Molnar:
 "Two changes that prettify and compactify the SMP bootup output from:

     smpboot: Booting Node   0, Processors  #1 #2 #3 OK
     smpboot: Booting Node   1, Processors  #4 #5 #6 #7 OK
     smpboot: Booting Node   2, Processors  #8 #9 #10 #11 OK
     smpboot: Booting Node   3, Processors  #12 #13 #14 #15 OK
     Brought up 16 CPUs

  to something like:

     x86: Booting SMP configuration:
     .... node  #0, CPUs:        #1  #2  #3
     .... node  #1, CPUs:    #4  #5  #6  #7
     .... node  #2, CPUs:    #8  #9 #10 #11
     .... node  #3, CPUs:   #12 #13 #14 #15
     x86: Booted up 4 nodes, 16 CPUs"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Further compress CPUs bootup message
  x86: Improve the printout of the SMP bootup CPU table
noglitch pushed a commit that referenced this pull request May 13, 2014
This patch fixes a bug in delayed Task Aborted Status (TAS) handling,
where transport_send_task_abort() was not returning for the case
when the se_tfo->write_pending() callback indicated that last fabric
specific WRITE PDU had not yet been received.

It also adds an explicit cmd->scsi_status = SAM_STAT_TASK_ABORTED
assignment within transport_check_aborted_status() to avoid the case
where se_tfo->queue_status() is called when the SAM_STAT_TASK_ABORTED
assignment + ->queue_status() in transport_send_task_abort() does not
occur once SCF_SENT_DELAYED_TAS has been set.

Cc: <stable@vger.kernel.org> #3.2+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
Hayes Wang says:

====================
r8152 bug fixes

For the patch #3, I add netif_tx_lock() before checking the
netif_queue_stopped(). Besides, I add checking the skb queue
length before waking the tx queue.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
noglitch pushed a commit that referenced this pull request May 13, 2014
extract_param() is called with max_length set to the total size of the
output buffer.  It's not safe to allow a parameter length equal to the
buffer size as the terminating null would be written one byte past the
end of the output buffer.

Signed-off-by: Eric Seppanen <eric@purestorage.com>
Cc: <stable@vger.kernel.org> #3.1+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
In iSCSI negotiations with initiator CHAP enabled, usernames with
trailing garbage are permitted, because the string comparison only
checks the strlen of the configured username.

e.g. "usernameXXXXX" will be permitted to match "username".

Just check one more byte so the trailing null char is also matched.

Signed-off-by: Eric Seppanen <eric@purestorage.com>
Cc: <stable@vger.kernel.org> #3.1+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
The following two commits implemented mmap support in the regular file
path and merged bin file support into the regular path.

 73d9714 ("sysfs: copy bin mmap support from fs/sysfs/bin.c to fs/sysfs/file.c")
 3124eb1 ("sysfs: merge regular and bin file handling")

After the merge, the following commands trigger a spurious lockdep
warning.  "test-mmap-read" simply mmaps the file and dumps the
content.

  $ cat /sys/block/sda/trace/act_mask
  $ test-mmap-read /sys/devices/pci0000\:00/0000\:00\:03.0/resource0 4096

  ======================================================
  [ INFO: possible circular locking dependency detected ]
  3.12.0-work+ #378 Not tainted
  -------------------------------------------------------
  test-mmap-read/567 is trying to acquire lock:
   (&of->mutex){+.+.+.}, at: [<ffffffff8120a8df>] sysfs_bin_mmap+0x4f/0x120

  but task is already holding lock:
   (&mm->mmap_sem){++++++}, at: [<ffffffff8114b399>] vm_mmap_pgoff+0x49/0xa0

  which lock already depends on the new lock.

  the existing dependency chain (in reverse order) is:

  -> #3 (&mm->mmap_sem){++++++}:
  ...
  -> #2 (sr_mutex){+.+.+.}:
  ...
  -> #1 (&bdev->bd_mutex){+.+.+.}:
  ...
  -> #0 (&of->mutex){+.+.+.}:
  ...

  other info that might help us debug this:

  Chain exists of:
   &of->mutex --> sr_mutex --> &mm->mmap_sem

   Possible unsafe locking scenario:

	 CPU0                    CPU1
	 ----                    ----
    lock(&mm->mmap_sem);
				 lock(sr_mutex);
				 lock(&mm->mmap_sem);
    lock(&of->mutex);

   *** DEADLOCK ***

  1 lock held by test-mmap-read/567:
   #0:  (&mm->mmap_sem){++++++}, at: [<ffffffff8114b399>] vm_mmap_pgoff+0x49/0xa0

  stack backtrace:
  CPU: 3 PID: 567 Comm: test-mmap-read Not tainted 3.12.0-work+ #378
  Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
   ffffffff81ed41a0 ffff880009441bc8 ffffffff81611ad2 ffffffff81eccb80
   ffff880009441c08 ffffffff8160f215 ffff880009441c60 ffff880009c75208
   0000000000000000 ffff880009c751e0 ffff880009c75208 ffff880009c74ac0
  Call Trace:
   [<ffffffff81611ad2>] dump_stack+0x4e/0x7a
   [<ffffffff8160f215>] print_circular_bug+0x2b0/0x2bf
   [<ffffffff8109ca0a>] __lock_acquire+0x1a3a/0x1e60
   [<ffffffff8109d6ba>] lock_acquire+0x9a/0x1d0
   [<ffffffff81615547>] mutex_lock_nested+0x67/0x3f0
   [<ffffffff8120a8df>] sysfs_bin_mmap+0x4f/0x120
   [<ffffffff8115d363>] mmap_region+0x3b3/0x5b0
   [<ffffffff8115d8ae>] do_mmap_pgoff+0x34e/0x3d0
   [<ffffffff8114b3ba>] vm_mmap_pgoff+0x6a/0xa0
   [<ffffffff8115be3e>] SyS_mmap_pgoff+0xbe/0x250
   [<ffffffff81008282>] SyS_mmap+0x22/0x30
   [<ffffffff8161a4d2>] system_call_fastpath+0x16/0x1b

This happens because one file nests sr_mutex, which nests mm->mmap_sem
under it, under of->mutex while mmap implementation naturally nests
of->mutex under mm->mmap_sem.  The warning is false positive as
of->mutex is per open-file and the two paths belong to two different
files.  This warning didn't trigger before regular and bin file
supports were merged because only bin file supported mmap and the
other side of locking happened only on regular files which used
equivalent but separate locking.

It'd be best if we give separate locking classes per file but we can't
easily do that.  Let's differentiate on ->mmap() for now.  Later we'll
add explicit file operations struct and can add per-ops lockdep key
there.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
When booting Nokia N900 smartphone with v3.12 + omap2plus_defconfig
(LOCKDEP enabled) and CONFIG_DISPLAY_PANEL_SONY_ACX565AKM enabled,
the following BUG is seen during the boot:

[    7.302154] =====================================
[    7.307128] [ BUG: bad unlock balance detected! ]
[    7.312103] 3.12.0-los.git-2093492-00120-g5e01dc7 #3 Not tainted
[    7.318450] -------------------------------------
[    7.323425] kworker/u2:1/12 is trying to release lock (&ddata->mutex) at:
[    7.330657] [<c031b760>] acx565akm_enable+0x12c/0x18c
[    7.335998] but there are no more locks to release!

Fix by removing double unlock and handling the locking completely inside
acx565akm_panel_power_on() when doing the power on.

Reported-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: stable@vger.kernel.org
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
ldesroches added a commit that referenced this pull request May 13, 2014
With some devices, transfer hangs during I2C frame transmission. This issue
disappears when reducing the internal frequency of the TWI IP. Even if it is
indicated that internal clock max frequency is 66MHz, it seems we have
oversampling on I2C signals making TWI believe that a transfer in progress
is done.

This fix has no impact on the I2C bus frequency.

Cc: <stable@vger.kernel.org> #3.10+
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
Dave Jones got the following lockdep splat:

>  ======================================================
>  [ INFO: possible circular locking dependency detected ]
>  3.12.0-rc3+ #92 Not tainted
>  -------------------------------------------------------
>  trinity-child2/15191 is trying to acquire lock:
>   (&rdp->nocb_wq){......}, at: [<ffffffff8108ff43>] __wake_up+0x23/0x50
>
> but task is already holding lock:
>   (&ctx->lock){-.-...}, at: [<ffffffff81154c19>] perf_event_exit_task+0x109/0x230
>
> which lock already depends on the new lock.
>
>
> the existing dependency chain (in reverse order) is:
>
> -> #3 (&ctx->lock){-.-...}:
>         [<ffffffff810cc243>] lock_acquire+0x93/0x200
>         [<ffffffff81733f90>] _raw_spin_lock+0x40/0x80
>         [<ffffffff811500ff>] __perf_event_task_sched_out+0x2df/0x5e0
>         [<ffffffff81091b83>] perf_event_task_sched_out+0x93/0xa0
>         [<ffffffff81732052>] __schedule+0x1d2/0xa20
>         [<ffffffff81732f30>] preempt_schedule_irq+0x50/0xb0
>         [<ffffffff817352b6>] retint_kernel+0x26/0x30
>         [<ffffffff813eed04>] tty_flip_buffer_push+0x34/0x50
>         [<ffffffff813f0504>] pty_write+0x54/0x60
>         [<ffffffff813e900d>] n_tty_write+0x32d/0x4e0
>         [<ffffffff813e5838>] tty_write+0x158/0x2d0
>         [<ffffffff811c4850>] vfs_write+0xc0/0x1f0
>         [<ffffffff811c52cc>] SyS_write+0x4c/0xa0
>         [<ffffffff8173d4e4>] tracesys+0xdd/0xe2
>
> -> #2 (&rq->lock){-.-.-.}:
>         [<ffffffff810cc243>] lock_acquire+0x93/0x200
>         [<ffffffff81733f90>] _raw_spin_lock+0x40/0x80
>         [<ffffffff810980b2>] wake_up_new_task+0xc2/0x2e0
>         [<ffffffff81054336>] do_fork+0x126/0x460
>         [<ffffffff81054696>] kernel_thread+0x26/0x30
>         [<ffffffff8171ff93>] rest_init+0x23/0x140
>         [<ffffffff81ee1e4b>] start_kernel+0x3f6/0x403
>         [<ffffffff81ee1571>] x86_64_start_reservations+0x2a/0x2c
>         [<ffffffff81ee1664>] x86_64_start_kernel+0xf1/0xf4
>
> -> #1 (&p->pi_lock){-.-.-.}:
>         [<ffffffff810cc243>] lock_acquire+0x93/0x200
>         [<ffffffff8173419b>] _raw_spin_lock_irqsave+0x4b/0x90
>         [<ffffffff810979d1>] try_to_wake_up+0x31/0x350
>         [<ffffffff81097d62>] default_wake_function+0x12/0x20
>         [<ffffffff81084af8>] autoremove_wake_function+0x18/0x40
>         [<ffffffff8108ea38>] __wake_up_common+0x58/0x90
>         [<ffffffff8108ff59>] __wake_up+0x39/0x50
>         [<ffffffff8110d4f8>] __call_rcu_nocb_enqueue+0xa8/0xc0
>         [<ffffffff81111450>] __call_rcu+0x140/0x820
>         [<ffffffff81111b8d>] call_rcu+0x1d/0x20
>         [<ffffffff81093697>] cpu_attach_domain+0x287/0x360
>         [<ffffffff81099d7e>] build_sched_domains+0xe5e/0x10a0
>         [<ffffffff81efa7fc>] sched_init_smp+0x3b7/0x47a
>         [<ffffffff81ee1f4e>] kernel_init_freeable+0xf6/0x202
>         [<ffffffff817200be>] kernel_init+0xe/0x190
>         [<ffffffff8173d22c>] ret_from_fork+0x7c/0xb0
>
> -> #0 (&rdp->nocb_wq){......}:
>         [<ffffffff810cb7ca>] __lock_acquire+0x191a/0x1be0
>         [<ffffffff810cc243>] lock_acquire+0x93/0x200
>         [<ffffffff8173419b>] _raw_spin_lock_irqsave+0x4b/0x90
>         [<ffffffff8108ff43>] __wake_up+0x23/0x50
>         [<ffffffff8110d4f8>] __call_rcu_nocb_enqueue+0xa8/0xc0
>         [<ffffffff81111450>] __call_rcu+0x140/0x820
>         [<ffffffff81111bb0>] kfree_call_rcu+0x20/0x30
>         [<ffffffff81149abf>] put_ctx+0x4f/0x70
>         [<ffffffff81154c3e>] perf_event_exit_task+0x12e/0x230
>         [<ffffffff81056b8d>] do_exit+0x30d/0xcc0
>         [<ffffffff8105893c>] do_group_exit+0x4c/0xc0
>         [<ffffffff810589c4>] SyS_exit_group+0x14/0x20
>         [<ffffffff8173d4e4>] tracesys+0xdd/0xe2
>
> other info that might help us debug this:
>
> Chain exists of:
>   &rdp->nocb_wq --> &rq->lock --> &ctx->lock
>
>   Possible unsafe locking scenario:
>
>         CPU0                    CPU1
>         ----                    ----
>    lock(&ctx->lock);
>                                 lock(&rq->lock);
>                                 lock(&ctx->lock);
>    lock(&rdp->nocb_wq);
>
>  *** DEADLOCK ***
>
> 1 lock held by trinity-child2/15191:
>  #0:  (&ctx->lock){-.-...}, at: [<ffffffff81154c19>] perf_event_exit_task+0x109/0x230
>
> stack backtrace:
> CPU: 2 PID: 15191 Comm: trinity-child2 Not tainted 3.12.0-rc3+ #92
>  ffffffff82565b70 ffff880070c2dbf8 ffffffff8172a363 ffffffff824edf40
>  ffff880070c2dc38 ffffffff81726741 ffff880070c2dc90 ffff88022383b1c0
>  ffff88022383aac0 0000000000000000 ffff88022383b188 ffff88022383b1c0
> Call Trace:
>  [<ffffffff8172a363>] dump_stack+0x4e/0x82
>  [<ffffffff81726741>] print_circular_bug+0x200/0x20f
>  [<ffffffff810cb7ca>] __lock_acquire+0x191a/0x1be0
>  [<ffffffff810c6439>] ? get_lock_stats+0x19/0x60
>  [<ffffffff8100b2f4>] ? native_sched_clock+0x24/0x80
>  [<ffffffff810cc243>] lock_acquire+0x93/0x200
>  [<ffffffff8108ff43>] ? __wake_up+0x23/0x50
>  [<ffffffff8173419b>] _raw_spin_lock_irqsave+0x4b/0x90
>  [<ffffffff8108ff43>] ? __wake_up+0x23/0x50
>  [<ffffffff8108ff43>] __wake_up+0x23/0x50
>  [<ffffffff8110d4f8>] __call_rcu_nocb_enqueue+0xa8/0xc0
>  [<ffffffff81111450>] __call_rcu+0x140/0x820
>  [<ffffffff8109bc8f>] ? local_clock+0x3f/0x50
>  [<ffffffff81111bb0>] kfree_call_rcu+0x20/0x30
>  [<ffffffff81149abf>] put_ctx+0x4f/0x70
>  [<ffffffff81154c3e>] perf_event_exit_task+0x12e/0x230
>  [<ffffffff81056b8d>] do_exit+0x30d/0xcc0
>  [<ffffffff810c9af5>] ? trace_hardirqs_on_caller+0x115/0x1e0
>  [<ffffffff810c9bcd>] ? trace_hardirqs_on+0xd/0x10
>  [<ffffffff8105893c>] do_group_exit+0x4c/0xc0
>  [<ffffffff810589c4>] SyS_exit_group+0x14/0x20
>  [<ffffffff8173d4e4>] tracesys+0xdd/0xe2

The underlying problem is that perf is invoking call_rcu() with the
scheduler locks held, but in NOCB mode, call_rcu() will with high
probability invoke the scheduler -- which just might want to use its
locks.  The reason that call_rcu() needs to invoke the scheduler is
to wake up the corresponding rcuo callback-offload kthread, which
does the job of starting up a grace period and invoking the callbacks
afterwards.

One solution (championed on a related problem by Lai Jiangshan) is to
simply defer the wakeup to some point where scheduler locks are no longer
held.  Since we don't want to unnecessarily incur the cost of such
deferral, the task before us is threefold:

1.	Determine when it is likely that a relevant scheduler lock is held.

2.	Defer the wakeup in such cases.

3.	Ensure that all deferred wakeups eventually happen, preferably
	sooner rather than later.

We use irqs_disabled_flags() as a proxy for relevant scheduler locks
being held.  This works because the relevant locks are always acquired
with interrupts disabled.  We may defer more often than needed, but that
is at least safe.

The wakeup deferral is tracked via a new field in the per-CPU and
per-RCU-flavor rcu_data structure, namely ->nocb_defer_wakeup.

This flag is checked by the RCU core processing.  The __rcu_pending()
function now checks this flag, which causes rcu_check_callbacks()
to initiate RCU core processing at each scheduling-clock interrupt
where this flag is set.  Of course this is not sufficient because
scheduling-clock interrupts are often turned off (the things we used to
be able to count on!).  So the flags are also checked on entry to any
state that RCU considers to be idle, which includes both NO_HZ_IDLE idle
state and NO_HZ_FULL user-mode-execution state.

This approach should allow call_rcu() to be invoked regardless of what
locks you might be holding, the key word being "should".

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
ldesroches added a commit that referenced this pull request May 13, 2014
pinctrl-names property was missing from mmc nodes.

Cc: <stable@vger.kernel.org> #3.11+
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
noglitch pushed a commit that referenced this pull request May 13, 2014
This patch changes special case handling for ISCSI_OP_SCSI_CMD
where an initiator sends a zero length Expected Data Transfer
Length (EDTL), but still sets the WRITE and/or READ flag bits
when no payload transfer is requested.

Many, many moons ago two special cases where added for an ancient
version of ESX that has long since been fixed, so instead of adding
a new special case for the reported bug with a Broadcom 57800 NIC,
go ahead and always strip off the incorrect WRITE + READ flag bits.

Also, avoid sending a reject here, as RFC-3720 does mandate this
case be handled without protocol error.

Reported-by: Witold Bazakbal <865perl@wp.pl>
Tested-by: Witold Bazakbal <865perl@wp.pl>
Cc: <stable@vger.kernel.org> #3.1+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: <stable@vger.kernel.org> #3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
This patch fixes two cases in qla_target.c code where the
schedule_delayed_work() value was being incorrectly calculated
from sess->expires - jiffies.

Signed-off-by: Shivaram U <shivaram.u@quadstor.com>
Cc: <stable@vger.kernel.org> #3.6+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
The Allwinner A20 uses the ARM GIC as its internal interrupts controller. The
GIC can work on several interrupt triggers, and the A20 was actually setting it
up to use a rising edge as a trigger, while it was actually a level high
trigger, leading to some interrupts that would be completely ignored if the
edge was missed.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Cc: stable@vger.kernel.org #3.12+
Signed-off-by: Olof Johansson <olof@lixom.net>
noglitch pushed a commit that referenced this pull request May 13, 2014
When shutting down a target there is a race condition between
iscsit_del_np() and __iscsi_target_login_thread().
The latter sets the thread pointer to NULL, and the former
tries to issue kthread_stop() on that pointer without any
synchronization.

This patch moves the np->np_thread NULL assignment into
iscsit_del_np(), after kthread_stop() has completed. It also
removes the signal_pending() + np_state check, and only
exits when kthread_should_stop() is true.

Reported-by: Hannes Reinecke <hare@suse.de>
Cc: <stable@vger.kernel.org> #3.12+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
This patch moves INIT_WORK setup for cq_desc->cq_[rx,tx]_work into
isert_create_device_ib_res(), instead of being done each callback
invocation in isert_cq_[rx,tx]_callback().

This also fixes a 'INFO: trying to register non-static key' warning
when cancel_work_sync() is called before INIT_WORK has setup the
struct work_struct.

Reported-by: Or Gerlitz <ogerlitz@mellanox.com>
Cc: <stable@vger.kernel.org> #3.12+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
This patch allows FILEIO to update hw_max_sectors based on the current
max_bytes_per_io.  This is required because vfs_[writev,readv]() can accept
a maximum of 2048 iovecs per call, so the enforced hw_max_sectors really
needs to be calculated based on block_size.

This addresses a >= v3.5 bug where block_size=512 was rejecting > 1M
sized I/O requests, because FD_MAX_SECTORS was hardcoded to 2048 for
the block_size=4096 case.

(v2: Use max_bytes_per_io instead of ->update_hw_max_sectors)

Reported-by: Henrik Goldman <hg@x-formation.com>
Cc: <stable@vger.kernel.org> #3.5+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
…to next/dt

From Jason Cooper:
mvebu DT changes for v3.14 (incr. #3)

 - kirkwood
    - use symbolic names for gpios and key inputs

 - mvebu
    - add the pxa nand controller to the ReadyNAS and A370-RD boards

* tag 'mvebu-dt-3.14-3' of git://git.infradead.org/linux-mvebu:
  ARM: mvebu: Enable NAND controller in A370 Reference Design board
  ARM: mvebu: Enable NAND controller in ReadyNAS 2120 .dts file
  ARM: mvebu: Enable NAND controller in ReadyNAS 104 .dts file
  ARM: mvebu: Enable NAND controller in ReadyNAS 102 .dts file
  ARM: DT: Kirkwood: Use symbolic names from gpio.h
  ARM: DT: Kirkwood: Use symbolic names from input.h

Signed-off-by: Kevin Hilman <khilman@linaro.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
Since 48cdc13 (Implement a shadow timekeeper), we have to
call timekeeping_update() after any adjustment to the timekeeping
structure in order to make sure that any adjustments to the structure
persist.

Unfortunately, the updates to the tai offset via adjtimex do not
trigger this update, causing adjustments to the tai offset to be
made and then over-written by the previous value at the next
update_wall_time() call.

This patch resovles the issue by calling timekeeping_update()
right after setting the tai offset.

Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable <stable@vger.kernel.org> #3.10+
Signed-off-by: John Stultz <john.stultz@linaro.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
In 780427f (Indicate that clock was set in the pvclock
gtod notifier), logic was added to pass a CLOCK_WAS_SET
notification to the pvclock notifier chain.

While that patch added a action flag returned from
accumulate_nsecs_to_secs(), it only uses the returned value
in one location, and not in the logarithmic accumulation.

This means if a leap second triggered during the logarithmic
accumulation (which is most likely where it would happen),
the notification that the clock was set would not make it to
the pv notifiers.

This patch extends the logarithmic_accumulation pass down
that action flag so proper notification will occur.

This patch also changes the varialbe action -> clock_set
per Ingo's suggestion.

Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: <xen-devel@lists.xen.org>
Cc: stable <stable@vger.kernel.org> #3.11+
Signed-off-by: John Stultz <john.stultz@linaro.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
As part of normal operaions, the hrtimer subsystem frequently calls
into the timekeeping code, creating a locking order of
  hrtimer locks -> timekeeping locks

clock_was_set_delayed() was suppoed to allow us to avoid deadlocks
between the timekeeping the hrtimer subsystem, so that we could
notify the hrtimer subsytem the time had changed while holding
the timekeeping locks. This was done by scheduling delayed work
that would run later once we were out of the timekeeing code.

But unfortunately the lock chains are complex enoguh that in
scheduling delayed work, we end up eventually trying to grab
an hrtimer lock.

Sasha Levin noticed this in testing when the new seqlock lockdep
enablement triggered the following (somewhat abrieviated) message:

[  251.100221] ======================================================
[  251.100221] [ INFO: possible circular locking dependency detected ]
[  251.100221] 3.13.0-rc2-next-20131206-sasha-00005-g8be2375-dirty #4053 Not tainted
[  251.101967] -------------------------------------------------------
[  251.101967] kworker/10:1/4506 is trying to acquire lock:
[  251.101967]  (timekeeper_seq){----..}, at: [<ffffffff81160e96>] retrigger_next_event+0x56/0x70
[  251.101967]
[  251.101967] but task is already holding lock:
[  251.101967]  (hrtimer_bases.lock#11){-.-...}, at: [<ffffffff81160e7c>] retrigger_next_event+0x3c/0x70
[  251.101967]
[  251.101967] which lock already depends on the new lock.
[  251.101967]
[  251.101967]
[  251.101967] the existing dependency chain (in reverse order) is:
[  251.101967]
-> #5 (hrtimer_bases.lock#11){-.-...}:
[snipped]
-> #4 (&rt_b->rt_runtime_lock){-.-...}:
[snipped]
-> #3 (&rq->lock){-.-.-.}:
[snipped]
-> #2 (&p->pi_lock){-.-.-.}:
[snipped]
-> #1 (&(&pool->lock)->rlock){-.-...}:
[  251.101967]        [<ffffffff81194803>] validate_chain+0x6c3/0x7b0
[  251.101967]        [<ffffffff81194d9d>] __lock_acquire+0x4ad/0x580
[  251.101967]        [<ffffffff81194ff2>] lock_acquire+0x182/0x1d0
[  251.101967]        [<ffffffff84398500>] _raw_spin_lock+0x40/0x80
[  251.101967]        [<ffffffff81153e69>] __queue_work+0x1a9/0x3f0
[  251.101967]        [<ffffffff81154168>] queue_work_on+0x98/0x120
[  251.101967]        [<ffffffff81161351>] clock_was_set_delayed+0x21/0x30
[  251.101967]        [<ffffffff811c4bd1>] do_adjtimex+0x111/0x160
[  251.101967]        [<ffffffff811e2711>] compat_sys_adjtimex+0x41/0x70
[  251.101967]        [<ffffffff843a4b49>] ia32_sysret+0x0/0x5
[  251.101967]
-> #0 (timekeeper_seq){----..}:
[snipped]
[  251.101967] other info that might help us debug this:
[  251.101967]
[  251.101967] Chain exists of:
  timekeeper_seq --> &rt_b->rt_runtime_lock --> hrtimer_bases.lock#11

[  251.101967]  Possible unsafe locking scenario:
[  251.101967]
[  251.101967]        CPU0                    CPU1
[  251.101967]        ----                    ----
[  251.101967]   lock(hrtimer_bases.lock#11);
[  251.101967]                                lock(&rt_b->rt_runtime_lock);
[  251.101967]                                lock(hrtimer_bases.lock#11);
[  251.101967]   lock(timekeeper_seq);
[  251.101967]
[  251.101967]  *** DEADLOCK ***
[  251.101967]
[  251.101967] 3 locks held by kworker/10:1/4506:
[  251.101967]  #0:  (events){.+.+.+}, at: [<ffffffff81154960>] process_one_work+0x200/0x530
[  251.101967]  #1:  (hrtimer_work){+.+...}, at: [<ffffffff81154960>] process_one_work+0x200/0x530
[  251.101967]  #2:  (hrtimer_bases.lock#11){-.-...}, at: [<ffffffff81160e7c>] retrigger_next_event+0x3c/0x70
[  251.101967]
[  251.101967] stack backtrace:
[  251.101967] CPU: 10 PID: 4506 Comm: kworker/10:1 Not tainted 3.13.0-rc2-next-20131206-sasha-00005-g8be2375-dirty #4053
[  251.101967] Workqueue: events clock_was_set_work

So the best solution is to avoid calling clock_was_set_delayed() while
holding the timekeeping lock, and instead using a flag variable to
decide if we should call clock_was_set() once we've released the locks.

This works for the case here, where the do_adjtimex() was the deadlock
trigger point. Unfortuantely, in update_wall_time() we still hold
the jiffies lock, which would deadlock with the ipi triggered by
clock_was_set(), preventing us from calling it even after we drop the
timekeeping lock. So instead call clock_was_set_delayed() at that point.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: stable <stable@vger.kernel.org> #3.10+
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Tested-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
noglitch pushed a commit that referenced this pull request May 13, 2014
A think-o in the calculation of the monotonic -> tai time offset
results in CLOCK_TAI timers and nanosleeps to expire late (the
latency is ~2x the tai offset).

Fix this by adding the tai offset from the realtime offset instead
of subtracting.

Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable <stable@vger.kernel.org> #3.10+
Signed-off-by: John Stultz <john.stultz@linaro.org>
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3 participants