linux/fs/fscache
Milosz Tanski 3e1199dcad FS-Cache: refcount becomes corrupt under vma pressure.
In rare cases under heavy VMA pressure the ref count for a fscache cookie
becomes corrupt. In this case we decrement ref count even if we fail before
incrementing the refcount.

FS-Cache: Assertion failed bnode-eca5f9c6/syslog
0 > 0 is false
------------[ cut here ]------------
kernel BUG at fs/fscache/cookie.c:519!
invalid opcode: 0000 [#1] SMP
Call Trace:
[<ffffffffa01ba060>] __fscache_relinquish_cookie+0x50/0x220 [fscache]
[<ffffffffa02d64ce>] ceph_fscache_unregister_inode_cookie+0x3e/0x50 [ceph]
[<ffffffffa02ae1d3>] ceph_destroy_inode+0x33/0x200 [ceph]
[<ffffffff811cf67e>] ? __fsnotify_inode_delete+0xe/0x10
[<ffffffff811a9e0c>] destroy_inode+0x3c/0x70
[<ffffffff811a9f51>] evict+0x111/0x180
[<ffffffff811aa763>] iput+0x103/0x190
[<ffffffff811a5de8>] __dentry_kill+0x1c8/0x220
[<ffffffff811a5f31>] shrink_dentry_list+0xf1/0x250
[<ffffffff811a762c>] prune_dcache_sb+0x4c/0x60
[<ffffffff811930af>] super_cache_scan+0xff/0x170
[<ffffffff8113d7a0>] shrink_slab_node+0x140/0x2c0
[<ffffffff8113f2da>] shrink_slab+0x8a/0x130
[<ffffffff81142572>] balance_pgdat+0x3e2/0x5d0
[<ffffffff811428ca>] kswapd+0x16a/0x4a0
[<ffffffff810a43f0>] ? __wake_up_sync+0x20/0x20
[<ffffffff81142760>] ? balance_pgdat+0x5d0/0x5d0
[<ffffffff81083e09>] kthread+0xc9/0xe0
[<ffffffff81010000>] ? ftrace_raw_event_xen_mmu_release_ptpage+0x70/0x90
[<ffffffff81083d40>] ? flush_kthread_worker+0xb0/0xb0
[<ffffffff8159f63c>] ret_from_fork+0x7c/0xb0
[<ffffffff81083d40>] ? flush_kthread_worker+0xb0/0xb0
RIP [<ffffffffa01b984b>] __fscache_disable_cookie+0x1db/0x210 [fscache]
RSP <ffff8803bc85f9b8>
---[ end trace 254d0d7c74a01f25 ]---

Signed-off-by: Milosz Tanski <milosz@adfin.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2014-09-17 22:41:40 +01:00
..
cache.c fs/fscache: convert printk to pr_foo() 2014-06-04 16:53:51 -07:00
cookie.c sched: Remove proliferation of wait_on_bit() action functions 2014-07-16 15:10:39 +02:00
fsdef.c FS-Cache: Provide the ability to enable/disable cookies 2013-09-27 18:40:25 +01:00
histogram.c fs/fscache: replace seq_printf by seq_puts 2014-06-04 16:53:52 -07:00
internal.h sched: Remove proliferation of wait_on_bit() action functions 2014-07-16 15:10:39 +02:00
Kconfig fscache: drop references to slow-work 2010-07-22 22:58:58 +02:00
main.c fs/fscache: make ctl_table static 2014-08-06 18:01:12 -07:00
Makefile FS-Cache: Allow the current state of all objects to be dumped 2009-11-19 18:11:04 +00:00
netfs.c fs/fscache: convert printk to pr_foo() 2014-06-04 16:53:51 -07:00
object-list.c fs/fscache: replace seq_printf by seq_puts 2014-06-04 16:53:52 -07:00
object.c FS-Cache: Reduce cookie ref count if submit fails. 2014-08-27 15:29:34 +01:00
operation.c fs/fscache: convert printk to pr_foo() 2014-06-04 16:53:51 -07:00
page.c FS-Cache: refcount becomes corrupt under vma pressure. 2014-09-17 22:41:40 +01:00
proc.c FS-Cache: Allow the current state of all objects to be dumped 2009-11-19 18:11:04 +00:00
stats.c fs/fscache/stats.c: fix memory leak 2013-04-29 15:54:27 -07:00