* Re: 2.6.26-rc1: possible circular locking dependency [not found] <a4423d670805101005x113c4813w2b95c1fb535cf080@mail.gmail.com> @ 2008-05-10 17:46 ` Kamalesh Babulal 2008-05-11 3:48 ` 2.6.26-rc1: possible circular locking dependency with xfs filesystem Kamalesh Babulal 0 siblings, 1 reply; 5+ messages in thread From: Kamalesh Babulal @ 2008-05-10 17:46 UTC (permalink / raw) To: Alexander Beregalov; +Cc: kernel-testers, kernel list, Ingo Molnar, peterz Adding the cc to kernel-list, Ingo Molnar and Peter Zijlstra Alexander Beregalov wrote: > [ INFO: possible circular locking dependency detected ] > 2.6.26-rc1-00279-g28a4acb #13 > ------------------------------------------------------- > nfsd/3087 is trying to acquire lock: > (iprune_mutex){--..}, at: [<c016f947>] shrink_icache_memory+0x38/0x19b > > but task is already holding lock: > (&(&ip->i_iolock)->mr_lock){----}, at: [<c0210b83>] xfs_ilock+0xa2/0xd6 > > which lock already depends on the new lock. > > > the existing dependency chain (in reverse order) is: > > -> #1 (&(&ip->i_iolock)->mr_lock){----}: > [<c01352e6>] __lock_acquire+0xa0c/0xbc6 > [<c013550a>] lock_acquire+0x6a/0x86 > [<c012c39a>] down_write_nested+0x33/0x6a > [<c0210b5c>] xfs_ilock+0x7b/0xd6 > [<c0210cd5>] xfs_ireclaim+0x1d/0x59 > [<c022edfe>] xfs_finish_reclaim+0x173/0x195 > [<c0230fa3>] xfs_reclaim+0xb3/0x138 > [<c023b4cb>] xfs_fs_clear_inode+0x55/0x8e > [<c016f60b>] clear_inode+0x83/0xd2 > [<c016f88a>] dispose_list+0x3c/0xc1 > [<c016fa82>] shrink_icache_memory+0x173/0x19b > [<c014a68d>] shrink_slab+0xda/0x14e > [<c014a8e5>] try_to_free_pages+0x1e4/0x2a2 > [<c0146997>] __alloc_pages_internal+0x23a/0x39d > [<c0146b11>] __alloc_pages+0xa/0xc > [<c01483b2>] __do_page_cache_readahead+0xaa/0x16a > [<c01484bc>] force_page_cache_readahead+0x4a/0x74 > [<c014c9b0>] sys_madvise+0x308/0x400 > [<c0102b25>] sysenter_past_esp+0x6a/0xb1 > [<ffffffff>] 0xffffffff > > -> #0 (iprune_mutex){--..}: > [<c0135203>] __lock_acquire+0x929/0xbc6 > [<c013550a>] lock_acquire+0x6a/0x86 > [<c0356a6f>] mutex_lock_nested+0xb4/0x226 > [<c016f947>] shrink_icache_memory+0x38/0x19b > [<c014a68d>] shrink_slab+0xda/0x14e > [<c014a8e5>] try_to_free_pages+0x1e4/0x2a2 > [<c0146997>] __alloc_pages_internal+0x23a/0x39d > [<c0146b11>] __alloc_pages+0xa/0xc > [<c01483b2>] __do_page_cache_readahead+0xaa/0x16a > [<c014866c>] ondemand_readahead+0x119/0x127 > [<c01486cc>] page_cache_async_readahead+0x52/0x5d > [<c0178e46>] generic_file_splice_read+0x290/0x4a8 > [<c0239f06>] xfs_splice_read+0x4b/0x78 > [<c0237713>] xfs_file_splice_read+0x24/0x29 > [<c0178182>] do_splice_to+0x45/0x63 > [<c01783f6>] splice_direct_to_actor+0xab/0x150 > [<c01ce8e1>] nfsd_vfs_read+0x1ed/0x2d0 > [<c01ced50>] nfsd_read+0x82/0x99 > [<c01d42bc>] nfsd3_proc_read+0xdf/0x12a > [<c01cb40b>] nfsd_dispatch+0xcf/0x19e > [<c033f484>] svc_process+0x3b3/0x68b > [<c01cb939>] nfsd+0x168/0x26b > [<c0103747>] kernel_thread_helper+0x7/0x10 > [<ffffffff>] 0xffffffff > > other info that might help us debug this: > > 3 locks held by nfsd/3087: > #0: (hash_sem){..--}, at: [<c01d1538>] exp_readlock+0xd/0xf > #1: (&(&ip->i_iolock)->mr_lock){----}, at: [<c0210b83>] xfs_ilock+0xa2/0xd6 > #2: (shrinker_rwsem){----}, at: [<c014a5d7>] shrink_slab+0x24/0x14e > > stack backtrace: > Pid: 3087, comm: nfsd Not tainted 2.6.26-rc1-00279-g28a4acb #13 > [<c0133498>] print_circular_bug_tail+0x5a/0x65 > [<c0133d99>] ? print_circular_bug_header+0xa8/0xb3 > [<c0135203>] __lock_acquire+0x929/0xbc6 > [<c0106c1a>] ? native_sched_clock+0x8b/0x9f > [<c013550a>] lock_acquire+0x6a/0x86 > [<c016f947>] ? shrink_icache_memory+0x38/0x19b > [<c0356a6f>] mutex_lock_nested+0xb4/0x226 > [<c016f947>] ? shrink_icache_memory+0x38/0x19b > [<c016f947>] ? shrink_icache_memory+0x38/0x19b > [<c016f947>] shrink_icache_memory+0x38/0x19b > [<c014a68d>] shrink_slab+0xda/0x14e > [<c014a8e5>] try_to_free_pages+0x1e4/0x2a2 > [<c03583c8>] ? _spin_unlock_irqrestore+0x36/0x58 > [<c014982f>] ? isolate_pages_global+0x0/0x3e > [<c0146997>] __alloc_pages_internal+0x23a/0x39d > [<c0146b11>] __alloc_pages+0xa/0xc > [<c01483b2>] __do_page_cache_readahead+0xaa/0x16a > [<c014866c>] ondemand_readahead+0x119/0x127 > [<c01486cc>] page_cache_async_readahead+0x52/0x5d > [<c0178e46>] generic_file_splice_read+0x290/0x4a8 > [<c0358305>] ? _spin_unlock+0x27/0x3c > [<c0250e55>] ? _atomic_dec_and_lock+0x25/0x30 > [<c016ed3f>] ? iput+0x24/0x4e > [<c0135484>] ? __lock_acquire+0xbaa/0xbc6 > [<c01cb12a>] ? exportfs_decode_fh+0x9b/0x1a1 > [<c0178245>] ? spd_release_page+0x0/0xf > [<c0239f06>] xfs_splice_read+0x4b/0x78 > [<c0237713>] xfs_file_splice_read+0x24/0x29 > [<c0178182>] do_splice_to+0x45/0x63 > [<c01783f6>] splice_direct_to_actor+0xab/0x150 > [<c01ce9c4>] ? nfsd_direct_splice_actor+0x0/0xf > [<c01ce8e1>] nfsd_vfs_read+0x1ed/0x2d0 > [<c01ced50>] nfsd_read+0x82/0x99 > [<c01d42bc>] nfsd3_proc_read+0xdf/0x12a > [<c01cb40b>] nfsd_dispatch+0xcf/0x19e > [<c033f484>] svc_process+0x3b3/0x68b > [<c01cb939>] nfsd+0x168/0x26b > [<c01cb7d1>] ? nfsd+0x0/0x26b > [<c0103747>] kernel_thread_helper+0x7/0x10 > -- > To unsubscribe from this list: send the line "unsubscribe kernel-testers" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Thanks & Regards, Kamalesh Babulal, Linux Technology Center, IBM, ISTL. ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: 2.6.26-rc1: possible circular locking dependency with xfs filesystem 2008-05-10 17:46 ` 2.6.26-rc1: possible circular locking dependency Kamalesh Babulal @ 2008-05-11 3:48 ` Kamalesh Babulal 2008-05-11 23:10 ` David Chinner 0 siblings, 1 reply; 5+ messages in thread From: Kamalesh Babulal @ 2008-05-11 3:48 UTC (permalink / raw) To: pvp-lsts Cc: Alexander Beregalov, kernel-testers, kernel list, Ingo Molnar, peterz, xfs, David Chinner Kamalesh Babulal wrote: > Adding the cc to kernel-list, Ingo Molnar and Peter Zijlstra > > Alexander Beregalov wrote: >> [ INFO: possible circular locking dependency detected ] >> 2.6.26-rc1-00279-g28a4acb #13 >> ------------------------------------------------------- >> nfsd/3087 is trying to acquire lock: >> (iprune_mutex){--..}, at: [<c016f947>] shrink_icache_memory+0x38/0x19b >> >> but task is already holding lock: >> (&(&ip->i_iolock)->mr_lock){----}, at: [<c0210b83>] xfs_ilock+0xa2/0xd6 >> >> which lock already depends on the new lock. >> >> >> the existing dependency chain (in reverse order) is: >> >> -> #1 (&(&ip->i_iolock)->mr_lock){----}: >> [<c01352e6>] __lock_acquire+0xa0c/0xbc6 >> [<c013550a>] lock_acquire+0x6a/0x86 >> [<c012c39a>] down_write_nested+0x33/0x6a >> [<c0210b5c>] xfs_ilock+0x7b/0xd6 >> [<c0210cd5>] xfs_ireclaim+0x1d/0x59 >> [<c022edfe>] xfs_finish_reclaim+0x173/0x195 >> [<c0230fa3>] xfs_reclaim+0xb3/0x138 >> [<c023b4cb>] xfs_fs_clear_inode+0x55/0x8e >> [<c016f60b>] clear_inode+0x83/0xd2 >> [<c016f88a>] dispose_list+0x3c/0xc1 >> [<c016fa82>] shrink_icache_memory+0x173/0x19b >> [<c014a68d>] shrink_slab+0xda/0x14e >> [<c014a8e5>] try_to_free_pages+0x1e4/0x2a2 >> [<c0146997>] __alloc_pages_internal+0x23a/0x39d >> [<c0146b11>] __alloc_pages+0xa/0xc >> [<c01483b2>] __do_page_cache_readahead+0xaa/0x16a >> [<c01484bc>] force_page_cache_readahead+0x4a/0x74 >> [<c014c9b0>] sys_madvise+0x308/0x400 >> [<c0102b25>] sysenter_past_esp+0x6a/0xb1 >> [<ffffffff>] 0xffffffff >> >> -> #0 (iprune_mutex){--..}: >> [<c0135203>] __lock_acquire+0x929/0xbc6 >> [<c013550a>] lock_acquire+0x6a/0x86 >> [<c0356a6f>] mutex_lock_nested+0xb4/0x226 >> [<c016f947>] shrink_icache_memory+0x38/0x19b >> [<c014a68d>] shrink_slab+0xda/0x14e >> [<c014a8e5>] try_to_free_pages+0x1e4/0x2a2 >> [<c0146997>] __alloc_pages_internal+0x23a/0x39d >> [<c0146b11>] __alloc_pages+0xa/0xc >> [<c01483b2>] __do_page_cache_readahead+0xaa/0x16a >> [<c014866c>] ondemand_readahead+0x119/0x127 >> [<c01486cc>] page_cache_async_readahead+0x52/0x5d >> [<c0178e46>] generic_file_splice_read+0x290/0x4a8 >> [<c0239f06>] xfs_splice_read+0x4b/0x78 >> [<c0237713>] xfs_file_splice_read+0x24/0x29 >> [<c0178182>] do_splice_to+0x45/0x63 >> [<c01783f6>] splice_direct_to_actor+0xab/0x150 >> [<c01ce8e1>] nfsd_vfs_read+0x1ed/0x2d0 >> [<c01ced50>] nfsd_read+0x82/0x99 >> [<c01d42bc>] nfsd3_proc_read+0xdf/0x12a >> [<c01cb40b>] nfsd_dispatch+0xcf/0x19e >> [<c033f484>] svc_process+0x3b3/0x68b >> [<c01cb939>] nfsd+0x168/0x26b >> [<c0103747>] kernel_thread_helper+0x7/0x10 >> [<ffffffff>] 0xffffffff >> >> other info that might help us debug this: >> >> 3 locks held by nfsd/3087: >> #0: (hash_sem){..--}, at: [<c01d1538>] exp_readlock+0xd/0xf >> #1: (&(&ip->i_iolock)->mr_lock){----}, at: [<c0210b83>] xfs_ilock+0xa2/0xd6 >> #2: (shrinker_rwsem){----}, at: [<c014a5d7>] shrink_slab+0x24/0x14e >> >> stack backtrace: >> Pid: 3087, comm: nfsd Not tainted 2.6.26-rc1-00279-g28a4acb #13 >> [<c0133498>] print_circular_bug_tail+0x5a/0x65 >> [<c0133d99>] ? print_circular_bug_header+0xa8/0xb3 >> [<c0135203>] __lock_acquire+0x929/0xbc6 >> [<c0106c1a>] ? native_sched_clock+0x8b/0x9f >> [<c013550a>] lock_acquire+0x6a/0x86 >> [<c016f947>] ? shrink_icache_memory+0x38/0x19b >> [<c0356a6f>] mutex_lock_nested+0xb4/0x226 >> [<c016f947>] ? shrink_icache_memory+0x38/0x19b >> [<c016f947>] ? shrink_icache_memory+0x38/0x19b >> [<c016f947>] shrink_icache_memory+0x38/0x19b >> [<c014a68d>] shrink_slab+0xda/0x14e >> [<c014a8e5>] try_to_free_pages+0x1e4/0x2a2 >> [<c03583c8>] ? _spin_unlock_irqrestore+0x36/0x58 >> [<c014982f>] ? isolate_pages_global+0x0/0x3e >> [<c0146997>] __alloc_pages_internal+0x23a/0x39d >> [<c0146b11>] __alloc_pages+0xa/0xc >> [<c01483b2>] __do_page_cache_readahead+0xaa/0x16a >> [<c014866c>] ondemand_readahead+0x119/0x127 >> [<c01486cc>] page_cache_async_readahead+0x52/0x5d >> [<c0178e46>] generic_file_splice_read+0x290/0x4a8 >> [<c0358305>] ? _spin_unlock+0x27/0x3c >> [<c0250e55>] ? _atomic_dec_and_lock+0x25/0x30 >> [<c016ed3f>] ? iput+0x24/0x4e >> [<c0135484>] ? __lock_acquire+0xbaa/0xbc6 >> [<c01cb12a>] ? exportfs_decode_fh+0x9b/0x1a1 >> [<c0178245>] ? spd_release_page+0x0/0xf >> [<c0239f06>] xfs_splice_read+0x4b/0x78 >> [<c0237713>] xfs_file_splice_read+0x24/0x29 >> [<c0178182>] do_splice_to+0x45/0x63 >> [<c01783f6>] splice_direct_to_actor+0xab/0x150 >> [<c01ce9c4>] ? nfsd_direct_splice_actor+0x0/0xf >> [<c01ce8e1>] nfsd_vfs_read+0x1ed/0x2d0 >> [<c01ced50>] nfsd_read+0x82/0x99 >> [<c01d42bc>] nfsd3_proc_read+0xdf/0x12a >> [<c01cb40b>] nfsd_dispatch+0xcf/0x19e >> [<c033f484>] svc_process+0x3b3/0x68b >> [<c01cb939>] nfsd+0x168/0x26b >> [<c01cb7d1>] ? nfsd+0x0/0x26b >> [<c0103747>] kernel_thread_helper+0x7/0x10 >> -- Adding the trimmed forward message of syslog from Plamen Petrov <pvp-lsts@fs.ru.acad.bg> May 9 02:16:46 nomad64 kernel: [42951853.992912] May 9 02:16:46 nomad64 kernel: [42951853.992913] ======================================================= May 9 02:16:46 nomad64 kernel: [42951853.992920] [ INFO: possible circular locking dependency detected ] May 9 02:16:46 nomad64 kernel: [42951853.992922] 2.6.26-rc1-00243-g46e4965 #1 May 9 02:16:46 nomad64 kernel: [42951853.992924] ------------------------------------------------------- May 9 02:16:46 nomad64 kernel: [42951853.992927] kio_http/3813 is trying to acquire lock: May 9 02:16:46 nomad64 kernel: [42951853.992930] (&mm->mmap_sem){----}, at: [<ffffffff80222bbd>] do_page_fault+0xdd/0x890 May 9 02:16:46 nomad64 kernel: [42951853.992944] May 9 02:16:46 nomad64 kernel: [42951853.992944] but task is already holding lock: May 9 02:16:46 nomad64 kernel: [42951853.992947] (&(&ip->i_iolock)->mr_lock){----}, at: [<ffffffff80387f85>] xfs_ilock+0x65/0xa0 May 9 02:16:46 nomad64 kernel: [42951853.992960] May 9 02:16:46 nomad64 kernel: [42951853.992960] which lock already depends on the new lock. May 9 02:16:46 nomad64 kernel: [42951853.992961] May 9 02:16:46 nomad64 kernel: [42951853.992964] May 9 02:16:46 nomad64 kernel: [42951853.992965] the existing dependency chain (in reverse order) is: May 9 02:16:46 nomad64 kernel: [42951853.992967] May 9 02:16:46 nomad64 kernel: [42951853.992968] -> #1 (&(&ip->i_iolock)->mr_lock){----}: May 9 02:16:46 nomad64 kernel: [42951853.992974] [<ffffffff80261d72>] __lock_acquire+0xf92/0x1080 May 9 02:16:46 nomad64 kernel: [42951853.992989] [<ffffffff80261f02>] lock_acquire+0xa2/0xd0 May 9 02:16:46 nomad64 kernel: [42951853.993002] [<ffffffff80255556>] down_write_nested+0x46/0x80 May 9 02:16:46 nomad64 kernel: [42951853.993018] [<ffffffff80387fb9>] xfs_ilock+0x99/0xa0 May 9 02:16:46 nomad64 kernel: [42951853.993034] [<ffffffff803a5117>] xfs_free_eofblocks+0x1c7/0x250 May 9 02:16:46 nomad64 kernel: [42951853.993049] [<ffffffff803a8a26>] xfs_release+0x186/0x1d0 May 9 02:16:46 nomad64 kernel: [42951853.993062] [<ffffffff803aeeb0>] xfs_file_release+0x10/0x20 May 9 02:16:46 nomad64 kernel: [42951853.993076] [<ffffffff802a01cc>] __fput+0xcc/0x1c0 May 9 02:16:46 nomad64 kernel: [42951853.993091] [<ffffffff802a05e6>] fput+0x16/0x20 May 9 02:16:46 nomad64 kernel: [42951853.993105] [<ffffffff8028865a>] remove_vma+0x4a/0x80 May 9 02:16:46 nomad64 kernel: [42951853.993120] [<ffffffff802894e1>] do_munmap+0x281/0x2e0 May 9 02:16:46 nomad64 kernel: [42951853.993134] [<ffffffff8028958b>] sys_munmap+0x4b/0x70 May 9 02:16:46 nomad64 kernel: [42951853.993148] [<ffffffff8020b62b>] system_call_after_swapgs+0x7b/0x80 May 9 02:16:46 nomad64 kernel: [42951853.993161] [<ffffffffffffffff>] 0xffffffffffffffff May 9 02:16:46 nomad64 kernel: [42951853.993178] May 9 02:16:46 nomad64 kernel: [42951853.993178] -> #0 (&mm->mmap_sem){----}: May 9 02:16:46 nomad64 kernel: [42951853.993185] [<ffffffff80261b90>] __lock_acquire+0xdb0/0x1080 May 9 02:16:46 nomad64 kernel: [42951853.993197] [<ffffffff80261f02>] lock_acquire+0xa2/0xd0 May 9 02:16:46 nomad64 kernel: [42951853.993213] [<ffffffff806b887b>] down_read+0x3b/0x70 May 9 02:16:46 nomad64 kernel: [42951853.993228] [<ffffffff80222bbd>] do_page_fault+0xdd/0x890 May 9 02:16:46 nomad64 kernel: [42951853.993241] [<ffffffff806ba5dd>] error_exit+0x0/0xa9 May 9 02:16:46 nomad64 kernel: [42951853.993256] [<ffffffffffffffff>] 0xffffffffffffffff May 9 02:16:46 nomad64 kernel: [42951853.993269] May 9 02:16:46 nomad64 kernel: [42951853.993270] other info that might help us debug this: May 9 02:16:46 nomad64 kernel: [42951853.993270] May 9 02:16:46 nomad64 kernel: [42951853.993273] 1 lock held by kio_http/3813: May 9 02:16:46 nomad64 kernel: [42951853.993275] #0: (&(&ip->i_iolock)->mr_lock){----}, at: [<ffffffff80387f85>] xfs_ilock+0x65/0xa0 May 9 02:16:46 nomad64 kernel: [42951853.993286] May 9 02:16:46 nomad64 kernel: [42951853.993287] stack backtrace: May 9 02:16:46 nomad64 kernel: [42951853.993290] Pid: 3813, comm: kio_http Not tainted 2.6.26-rc1-00243-g46e4965 #1 May 9 02:16:46 nomad64 kernel: [42951853.993292] May 9 02:16:46 nomad64 kernel: [42951853.993293] Call Trace: May 9 02:16:46 nomad64 kernel: [42951853.993297] [<ffffffff8025f2b3>] print_circular_bug_tail+0x83/0x90 May 9 02:16:46 nomad64 kernel: [42951853.993302] [<ffffffff80261b90>] __lock_acquire+0xdb0/0x1080 May 9 02:16:46 nomad64 kernel: [42951853.993306] [<ffffffff80222bbd>] ? do_page_fault+0xdd/0x890 May 9 02:16:46 nomad64 kernel: [42951853.993310] [<ffffffff80261f02>] lock_acquire+0xa2/0xd0 May 9 02:16:46 nomad64 kernel: [42951853.993313] [<ffffffff80222bbd>] ? do_page_fault+0xdd/0x890 May 9 02:16:46 nomad64 kernel: [42951853.993317] [<ffffffff806b887b>] down_read+0x3b/0x70 May 9 02:16:46 nomad64 kernel: [42951853.993320] [<ffffffff80222bbd>] do_page_fault+0xdd/0x890 May 9 02:16:46 nomad64 kernel: [42951853.993324] [<ffffffff806ba5dd>] error_exit+0x0/0xa9 May 9 02:16:46 nomad64 kernel: [42951853.993328] [<ffffffff802739b6>] ? file_read_actor+0x46/0x1b0 May 9 02:16:46 nomad64 kernel: [42951853.993331] [<ffffffff806ba3d6>] ? _read_unlock_irq+0x36/0x60 May 9 02:16:46 nomad64 kernel: [42951853.993335] [<ffffffff80275dbc>] ? generic_file_aio_read+0x2cc/0x5d0 May 9 02:16:46 nomad64 kernel: [42951853.993339] [<ffffffff8025ddb9>] ? get_lock_stats+0x19/0x70 May 9 02:16:46 nomad64 kernel: [42951853.993343] [<ffffffff803b2769>] ? xfs_read+0x139/0x220 May 9 02:16:46 nomad64 kernel: [42951853.993347] [<ffffffff803af06d>] ? xfs_file_aio_read+0x4d/0x60 May 9 02:16:46 nomad64 kernel: [42951853.993350] [<ffffffff8029eeb1>] ? do_sync_read+0xf1/0x130 May 9 02:16:46 nomad64 kernel: [42951853.993354] [<ffffffff802516e0>] ? autoremove_wake_function+0x0/0x40 May 9 02:16:46 nomad64 kernel: [42951853.993358] [<ffffffff8026089a>] ? trace_hardirqs_on+0xda/0x170 May 9 02:16:46 nomad64 kernel: [42951853.993361] [<ffffffff80272e45>] ? __rcu_read_unlock+0xb5/0xc0 May 9 02:16:46 nomad64 kernel: [42951853.993365] [<ffffffff8026089a>] ? trace_hardirqs_on+0xda/0x170 May 9 02:16:46 nomad64 kernel: [42951853.993369] [<ffffffff803c4381>] ? security_file_permission+0x11/0x20 May 9 02:16:46 nomad64 kernel: [42951853.993374] [<ffffffff8029f794>] ? vfs_read+0xc4/0x160 May 9 02:16:46 nomad64 kernel: [42951853.993377] [<ffffffff8029fc30>] ? sys_read+0x50/0x90 May 9 02:16:46 nomad64 kernel: [42951853.993380] [<ffffffff8020b62b>] ? system_call_after_swapgs+0x7b/0x80 -- Thanks & Regards, Kamalesh Babulal, Linux Technology Center, IBM, ISTL. ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: 2.6.26-rc1: possible circular locking dependency with xfs filesystem 2008-05-11 3:48 ` 2.6.26-rc1: possible circular locking dependency with xfs filesystem Kamalesh Babulal @ 2008-05-11 23:10 ` David Chinner 2008-05-15 17:45 ` Alexander Beregalov 0 siblings, 1 reply; 5+ messages in thread From: David Chinner @ 2008-05-11 23:10 UTC (permalink / raw) To: Kamalesh Babulal Cc: pvp-lsts, Alexander Beregalov, kernel-testers, kernel list, Ingo Molnar, peterz, xfs, David Chinner On Sun, May 11, 2008 at 09:18:07AM +0530, Kamalesh Babulal wrote: > Kamalesh Babulal wrote: > > Adding the cc to kernel-list, Ingo Molnar and Peter Zijlstra > > > > Alexander Beregalov wrote: > >> [ INFO: possible circular locking dependency detected ] > >> 2.6.26-rc1-00279-g28a4acb #13 > >> ------------------------------------------------------- > >> nfsd/3087 is trying to acquire lock: > >> (iprune_mutex){--..}, at: [<c016f947>] shrink_icache_memory+0x38/0x19b > >> > >> but task is already holding lock: > >> (&(&ip->i_iolock)->mr_lock){----}, at: [<c0210b83>] xfs_ilock+0xa2/0xd6 > >> > >> which lock already depends on the new lock. > >> > >> > >> the existing dependency chain (in reverse order) is: > >> > >> -> #1 (&(&ip->i_iolock)->mr_lock){----}: > >> [<c01352e6>] __lock_acquire+0xa0c/0xbc6 > >> [<c013550a>] lock_acquire+0x6a/0x86 > >> [<c012c39a>] down_write_nested+0x33/0x6a > >> [<c0210b5c>] xfs_ilock+0x7b/0xd6 > >> [<c0210cd5>] xfs_ireclaim+0x1d/0x59 > >> [<c022edfe>] xfs_finish_reclaim+0x173/0x195 > >> [<c0230fa3>] xfs_reclaim+0xb3/0x138 > >> [<c023b4cb>] xfs_fs_clear_inode+0x55/0x8e > >> [<c016f60b>] clear_inode+0x83/0xd2 > >> [<c016f88a>] dispose_list+0x3c/0xc1 > >> [<c016fa82>] shrink_icache_memory+0x173/0x19b > >> [<c014a68d>] shrink_slab+0xda/0x14e > >> [<c014a8e5>] try_to_free_pages+0x1e4/0x2a2 > >> [<c0146997>] __alloc_pages_internal+0x23a/0x39d > >> [<c0146b11>] __alloc_pages+0xa/0xc > >> [<c01483b2>] __do_page_cache_readahead+0xaa/0x16a > >> [<c01484bc>] force_page_cache_readahead+0x4a/0x74 > >> [<c014c9b0>] sys_madvise+0x308/0x400 > >> [<c0102b25>] sysenter_past_esp+0x6a/0xb1 > >> [<ffffffff>] 0xffffffff > >> > >> -> #0 (iprune_mutex){--..}: > >> [<c0135203>] __lock_acquire+0x929/0xbc6 > >> [<c013550a>] lock_acquire+0x6a/0x86 > >> [<c0356a6f>] mutex_lock_nested+0xb4/0x226 > >> [<c016f947>] shrink_icache_memory+0x38/0x19b > >> [<c014a68d>] shrink_slab+0xda/0x14e > >> [<c014a8e5>] try_to_free_pages+0x1e4/0x2a2 > >> [<c0146997>] __alloc_pages_internal+0x23a/0x39d > >> [<c0146b11>] __alloc_pages+0xa/0xc > >> [<c01483b2>] __do_page_cache_readahead+0xaa/0x16a > >> [<c014866c>] ondemand_readahead+0x119/0x127 > >> [<c01486cc>] page_cache_async_readahead+0x52/0x5d > >> [<c0178e46>] generic_file_splice_read+0x290/0x4a8 > >> [<c0239f06>] xfs_splice_read+0x4b/0x78 > >> [<c0237713>] xfs_file_splice_read+0x24/0x29 > >> [<c0178182>] do_splice_to+0x45/0x63 > >> [<c01783f6>] splice_direct_to_actor+0xab/0x150 > >> [<c01ce8e1>] nfsd_vfs_read+0x1ed/0x2d0 > >> [<c01ced50>] nfsd_read+0x82/0x99 > >> [<c01d42bc>] nfsd3_proc_read+0xdf/0x12a > >> [<c01cb40b>] nfsd_dispatch+0xcf/0x19e > >> [<c033f484>] svc_process+0x3b3/0x68b > >> [<c01cb939>] nfsd+0x168/0x26b > >> [<c0103747>] kernel_thread_helper+0x7/0x10 > >> [<ffffffff>] 0xffffffff Oh, yeah, that. Direct inode reclaim through memory pressure. Effectively memory reclaim inverts locking order w.r.t. iprune_mutex when it recurses into the filesystem. False positive - can never cause a deadlock on XFS. Can't be solved from the XFS side of things without effectively turning off lockdep checking for xfs inode locking. The fix is needed to lockdep via iprune_mutex annotations here.... > May 9 02:16:46 nomad64 kernel: [42951853.992965] the existing dependency chain (in reverse order) is: > May 9 02:16:46 nomad64 kernel: [42951853.992967] > May 9 02:16:46 nomad64 kernel: [42951853.992968] -> #1 (&(&ip->i_iolock)->mr_lock){----}: > May 9 02:16:46 nomad64 kernel: [42951853.992974] [<ffffffff80261d72>] __lock_acquire+0xf92/0x1080 > May 9 02:16:46 nomad64 kernel: [42951853.992989] [<ffffffff80261f02>] lock_acquire+0xa2/0xd0 > May 9 02:16:46 nomad64 kernel: [42951853.993002] [<ffffffff80255556>] down_write_nested+0x46/0x80 > May 9 02:16:46 nomad64 kernel: [42951853.993018] [<ffffffff80387fb9>] xfs_ilock+0x99/0xa0 > May 9 02:16:46 nomad64 kernel: [42951853.993034] [<ffffffff803a5117>] xfs_free_eofblocks+0x1c7/0x250 > May 9 02:16:46 nomad64 kernel: [42951853.993049] [<ffffffff803a8a26>] xfs_release+0x186/0x1d0 > May 9 02:16:46 nomad64 kernel: [42951853.993062] [<ffffffff803aeeb0>] xfs_file_release+0x10/0x20 > May 9 02:16:46 nomad64 kernel: [42951853.993076] [<ffffffff802a01cc>] __fput+0xcc/0x1c0 > May 9 02:16:46 nomad64 kernel: [42951853.993091] [<ffffffff802a05e6>] fput+0x16/0x20 > May 9 02:16:46 nomad64 kernel: [42951853.993105] [<ffffffff8028865a>] remove_vma+0x4a/0x80 > May 9 02:16:46 nomad64 kernel: [42951853.993120] [<ffffffff802894e1>] do_munmap+0x281/0x2e0 > May 9 02:16:46 nomad64 kernel: [42951853.993134] [<ffffffff8028958b>] sys_munmap+0x4b/0x70 > May 9 02:16:46 nomad64 kernel: [42951853.993148] [<ffffffff8020b62b>] system_call_after_swapgs+0x7b/0x80 > May 9 02:16:46 nomad64 kernel: [42951853.993161] [<ffffffffffffffff>] 0xffffffffffffffff hmmmm. Sounds like: fd = open() addr = mmap(fd) close(fd) ..... munmap(addr); But yes, XFS takes locks in ->release which means..... > May 9 02:16:46 nomad64 kernel: [42951853.993293] Call Trace: > May 9 02:16:46 nomad64 kernel: [42951853.993297] [<ffffffff8025f2b3>] print_circular_bug_tail+0x83/0x90 > May 9 02:16:46 nomad64 kernel: [42951853.993302] [<ffffffff80261b90>] __lock_acquire+0xdb0/0x1080 > May 9 02:16:46 nomad64 kernel: [42951853.993306] [<ffffffff80222bbd>] ? do_page_fault+0xdd/0x890 > May 9 02:16:46 nomad64 kernel: [42951853.993310] [<ffffffff80261f02>] lock_acquire+0xa2/0xd0 > May 9 02:16:46 nomad64 kernel: [42951853.993313] [<ffffffff80222bbd>] ? do_page_fault+0xdd/0x890 > May 9 02:16:46 nomad64 kernel: [42951853.993317] [<ffffffff806b887b>] down_read+0x3b/0x70 > May 9 02:16:46 nomad64 kernel: [42951853.993320] [<ffffffff80222bbd>] do_page_fault+0xdd/0x890 > May 9 02:16:46 nomad64 kernel: [42951853.993324] [<ffffffff806ba5dd>] error_exit+0x0/0xa9 > May 9 02:16:46 nomad64 kernel: [42951853.993328] [<ffffffff802739b6>] ? file_read_actor+0x46/0x1b0 > May 9 02:16:46 nomad64 kernel: [42951853.993331] [<ffffffff806ba3d6>] ? _read_unlock_irq+0x36/0x60 > May 9 02:16:46 nomad64 kernel: [42951853.993335] [<ffffffff80275dbc>] ? generic_file_aio_read+0x2cc/0x5d0 > May 9 02:16:46 nomad64 kernel: [42951853.993339] [<ffffffff8025ddb9>] ? get_lock_stats+0x19/0x70 > May 9 02:16:46 nomad64 kernel: [42951853.993343] [<ffffffff803b2769>] ? xfs_read+0x139/0x220 > May 9 02:16:46 nomad64 kernel: [42951853.993347] [<ffffffff803af06d>] ? xfs_file_aio_read+0x4d/0x60 > May 9 02:16:46 nomad64 kernel: [42951853.993350] [<ffffffff8029eeb1>] ? do_sync_read+0xf1/0x130 > May 9 02:16:46 nomad64 kernel: [42951853.993354] [<ffffffff802516e0>] ? autoremove_wake_function+0x0/0x40 > May 9 02:16:46 nomad64 kernel: [42951853.993358] [<ffffffff8026089a>] ? trace_hardirqs_on+0xda/0x170 > May 9 02:16:46 nomad64 kernel: [42951853.993361] [<ffffffff80272e45>] ? __rcu_read_unlock+0xb5/0xc0 > May 9 02:16:46 nomad64 kernel: [42951853.993365] [<ffffffff8026089a>] ? trace_hardirqs_on+0xda/0x170 > May 9 02:16:46 nomad64 kernel: [42951853.993369] [<ffffffff803c4381>] ? security_file_permission+0x11/0x20 > May 9 02:16:46 nomad64 kernel: [42951853.993374] [<ffffffff8029f794>] ? vfs_read+0xc4/0x160 > May 9 02:16:46 nomad64 kernel: [42951853.993377] [<ffffffff8029fc30>] ? sys_read+0x50/0x90 > May 9 02:16:46 nomad64 kernel: [42951853.993380] [<ffffffff8020b62b>] ? system_call_after_swapgs+0x7b/0x80 Oh, joy - a page fault during a read() call triggers lock order inversions on the mmap->sem. I don't think this can deadlock (can't be page faulting in a vma that is being torn down), but it's clear from the last trace that the VM has a mmap->sem inversion problem with ->release vs ->read and page faults... Basically what we are seeing here in both cases is that the VM is calling inode ->release or ->clear_inode methods with different high level locks held. If the filesystem has to take the same locks in these methods as it does in, say, ->read (like XFS does), then we are guaranteed to get reports like this. AFAICT there's nothing we can do from the filesystem perspective to prevent false positives like this from being reported.... Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: 2.6.26-rc1: possible circular locking dependency with xfs filesystem 2008-05-11 23:10 ` David Chinner @ 2008-05-15 17:45 ` Alexander Beregalov 2008-05-15 22:27 ` David Chinner 0 siblings, 1 reply; 5+ messages in thread From: Alexander Beregalov @ 2008-05-15 17:45 UTC (permalink / raw) To: David Chinner Cc: Kamalesh Babulal, pvp-lsts, kernel-testers, kernel list, Ingo Molnar, peterz, xfs 2008/5/12 David Chinner <dgc@sgi.com>: > On Sun, May 11, 2008 at 09:18:07AM +0530, Kamalesh Babulal wrote: >> Kamalesh Babulal wrote: >> > Adding the cc to kernel-list, Ingo Molnar and Peter Zijlstra >> > >> > Alexander Beregalov wrote: >> >> [ INFO: possible circular locking dependency detected ] >> >> 2.6.26-rc1-00279-g28a4acb #13 >> >> ------------------------------------------------------- >> >> nfsd/3087 is trying to acquire lock: >> >> (iprune_mutex){--..}, at: [<c016f947>] shrink_icache_memory+0x38/0x19b >> >> >> >> but task is already holding lock: >> >> (&(&ip->i_iolock)->mr_lock){----}, at: [<c0210b83>] xfs_ilock+0xa2/0xd6 >> >> >> >> which lock already depends on the new lock. >> >> >> >> >> >> the existing dependency chain (in reverse order) is: >> >> >> >> -> #1 (&(&ip->i_iolock)->mr_lock){----}: >> >> [<c01352e6>] __lock_acquire+0xa0c/0xbc6 >> >> [<c013550a>] lock_acquire+0x6a/0x86 >> >> [<c012c39a>] down_write_nested+0x33/0x6a >> >> [<c0210b5c>] xfs_ilock+0x7b/0xd6 >> >> [<c0210cd5>] xfs_ireclaim+0x1d/0x59 >> >> [<c022edfe>] xfs_finish_reclaim+0x173/0x195 >> >> [<c0230fa3>] xfs_reclaim+0xb3/0x138 >> >> [<c023b4cb>] xfs_fs_clear_inode+0x55/0x8e >> >> [<c016f60b>] clear_inode+0x83/0xd2 >> >> [<c016f88a>] dispose_list+0x3c/0xc1 >> >> [<c016fa82>] shrink_icache_memory+0x173/0x19b >> >> [<c014a68d>] shrink_slab+0xda/0x14e >> >> [<c014a8e5>] try_to_free_pages+0x1e4/0x2a2 >> >> [<c0146997>] __alloc_pages_internal+0x23a/0x39d >> >> [<c0146b11>] __alloc_pages+0xa/0xc >> >> [<c01483b2>] __do_page_cache_readahead+0xaa/0x16a >> >> [<c01484bc>] force_page_cache_readahead+0x4a/0x74 >> >> [<c014c9b0>] sys_madvise+0x308/0x400 >> >> [<c0102b25>] sysenter_past_esp+0x6a/0xb1 >> >> [<ffffffff>] 0xffffffff >> >> >> >> -> #0 (iprune_mutex){--..}: >> >> [<c0135203>] __lock_acquire+0x929/0xbc6 >> >> [<c013550a>] lock_acquire+0x6a/0x86 >> >> [<c0356a6f>] mutex_lock_nested+0xb4/0x226 >> >> [<c016f947>] shrink_icache_memory+0x38/0x19b >> >> [<c014a68d>] shrink_slab+0xda/0x14e >> >> [<c014a8e5>] try_to_free_pages+0x1e4/0x2a2 >> >> [<c0146997>] __alloc_pages_internal+0x23a/0x39d >> >> [<c0146b11>] __alloc_pages+0xa/0xc >> >> [<c01483b2>] __do_page_cache_readahead+0xaa/0x16a >> >> [<c014866c>] ondemand_readahead+0x119/0x127 >> >> [<c01486cc>] page_cache_async_readahead+0x52/0x5d >> >> [<c0178e46>] generic_file_splice_read+0x290/0x4a8 >> >> [<c0239f06>] xfs_splice_read+0x4b/0x78 >> >> [<c0237713>] xfs_file_splice_read+0x24/0x29 >> >> [<c0178182>] do_splice_to+0x45/0x63 >> >> [<c01783f6>] splice_direct_to_actor+0xab/0x150 >> >> [<c01ce8e1>] nfsd_vfs_read+0x1ed/0x2d0 >> >> [<c01ced50>] nfsd_read+0x82/0x99 >> >> [<c01d42bc>] nfsd3_proc_read+0xdf/0x12a >> >> [<c01cb40b>] nfsd_dispatch+0xcf/0x19e >> >> [<c033f484>] svc_process+0x3b3/0x68b >> >> [<c01cb939>] nfsd+0x168/0x26b >> >> [<c0103747>] kernel_thread_helper+0x7/0x10 >> >> [<ffffffff>] 0xffffffff > > Oh, yeah, that. Direct inode reclaim through memory pressure. > > Effectively memory reclaim inverts locking order w.r.t. iprune_mutex > when it recurses into the filesystem. False positive - can never > cause a deadlock on XFS. Can't be solved from the XFS side of things > without effectively turning off lockdep checking for xfs inode > locking. Yes, it is not a deadlock, but machine hangs for few seconds. It still happens about once a day for me. Every kernel report looks similar to the above. I cannot reproduce it quickly, so bisect is not possible. > > The fix is needed to lockdep via iprune_mutex annotations here.... > >> May 9 02:16:46 nomad64 kernel: [42951853.992965] the existing dependency chain (in reverse order) is: >> May 9 02:16:46 nomad64 kernel: [42951853.992967] >> May 9 02:16:46 nomad64 kernel: [42951853.992968] -> #1 (&(&ip->i_iolock)->mr_lock){----}: >> May 9 02:16:46 nomad64 kernel: [42951853.992974] [<ffffffff80261d72>] __lock_acquire+0xf92/0x1080 >> May 9 02:16:46 nomad64 kernel: [42951853.992989] [<ffffffff80261f02>] lock_acquire+0xa2/0xd0 >> May 9 02:16:46 nomad64 kernel: [42951853.993002] [<ffffffff80255556>] down_write_nested+0x46/0x80 >> May 9 02:16:46 nomad64 kernel: [42951853.993018] [<ffffffff80387fb9>] xfs_ilock+0x99/0xa0 >> May 9 02:16:46 nomad64 kernel: [42951853.993034] [<ffffffff803a5117>] xfs_free_eofblocks+0x1c7/0x250 >> May 9 02:16:46 nomad64 kernel: [42951853.993049] [<ffffffff803a8a26>] xfs_release+0x186/0x1d0 >> May 9 02:16:46 nomad64 kernel: [42951853.993062] [<ffffffff803aeeb0>] xfs_file_release+0x10/0x20 >> May 9 02:16:46 nomad64 kernel: [42951853.993076] [<ffffffff802a01cc>] __fput+0xcc/0x1c0 >> May 9 02:16:46 nomad64 kernel: [42951853.993091] [<ffffffff802a05e6>] fput+0x16/0x20 >> May 9 02:16:46 nomad64 kernel: [42951853.993105] [<ffffffff8028865a>] remove_vma+0x4a/0x80 >> May 9 02:16:46 nomad64 kernel: [42951853.993120] [<ffffffff802894e1>] do_munmap+0x281/0x2e0 >> May 9 02:16:46 nomad64 kernel: [42951853.993134] [<ffffffff8028958b>] sys_munmap+0x4b/0x70 >> May 9 02:16:46 nomad64 kernel: [42951853.993148] [<ffffffff8020b62b>] system_call_after_swapgs+0x7b/0x80 >> May 9 02:16:46 nomad64 kernel: [42951853.993161] [<ffffffffffffffff>] 0xffffffffffffffff > > hmmmm. Sounds like: > > fd = open() > addr = mmap(fd) > close(fd) > ..... > munmap(addr); > > But yes, XFS takes locks in ->release which means..... > >> May 9 02:16:46 nomad64 kernel: [42951853.993293] Call Trace: >> May 9 02:16:46 nomad64 kernel: [42951853.993297] [<ffffffff8025f2b3>] print_circular_bug_tail+0x83/0x90 >> May 9 02:16:46 nomad64 kernel: [42951853.993302] [<ffffffff80261b90>] __lock_acquire+0xdb0/0x1080 >> May 9 02:16:46 nomad64 kernel: [42951853.993306] [<ffffffff80222bbd>] ? do_page_fault+0xdd/0x890 >> May 9 02:16:46 nomad64 kernel: [42951853.993310] [<ffffffff80261f02>] lock_acquire+0xa2/0xd0 >> May 9 02:16:46 nomad64 kernel: [42951853.993313] [<ffffffff80222bbd>] ? do_page_fault+0xdd/0x890 >> May 9 02:16:46 nomad64 kernel: [42951853.993317] [<ffffffff806b887b>] down_read+0x3b/0x70 >> May 9 02:16:46 nomad64 kernel: [42951853.993320] [<ffffffff80222bbd>] do_page_fault+0xdd/0x890 >> May 9 02:16:46 nomad64 kernel: [42951853.993324] [<ffffffff806ba5dd>] error_exit+0x0/0xa9 >> May 9 02:16:46 nomad64 kernel: [42951853.993328] [<ffffffff802739b6>] ? file_read_actor+0x46/0x1b0 >> May 9 02:16:46 nomad64 kernel: [42951853.993331] [<ffffffff806ba3d6>] ? _read_unlock_irq+0x36/0x60 >> May 9 02:16:46 nomad64 kernel: [42951853.993335] [<ffffffff80275dbc>] ? generic_file_aio_read+0x2cc/0x5d0 >> May 9 02:16:46 nomad64 kernel: [42951853.993339] [<ffffffff8025ddb9>] ? get_lock_stats+0x19/0x70 >> May 9 02:16:46 nomad64 kernel: [42951853.993343] [<ffffffff803b2769>] ? xfs_read+0x139/0x220 >> May 9 02:16:46 nomad64 kernel: [42951853.993347] [<ffffffff803af06d>] ? xfs_file_aio_read+0x4d/0x60 >> May 9 02:16:46 nomad64 kernel: [42951853.993350] [<ffffffff8029eeb1>] ? do_sync_read+0xf1/0x130 >> May 9 02:16:46 nomad64 kernel: [42951853.993354] [<ffffffff802516e0>] ? autoremove_wake_function+0x0/0x40 >> May 9 02:16:46 nomad64 kernel: [42951853.993358] [<ffffffff8026089a>] ? trace_hardirqs_on+0xda/0x170 >> May 9 02:16:46 nomad64 kernel: [42951853.993361] [<ffffffff80272e45>] ? __rcu_read_unlock+0xb5/0xc0 >> May 9 02:16:46 nomad64 kernel: [42951853.993365] [<ffffffff8026089a>] ? trace_hardirqs_on+0xda/0x170 >> May 9 02:16:46 nomad64 kernel: [42951853.993369] [<ffffffff803c4381>] ? security_file_permission+0x11/0x20 >> May 9 02:16:46 nomad64 kernel: [42951853.993374] [<ffffffff8029f794>] ? vfs_read+0xc4/0x160 >> May 9 02:16:46 nomad64 kernel: [42951853.993377] [<ffffffff8029fc30>] ? sys_read+0x50/0x90 >> May 9 02:16:46 nomad64 kernel: [42951853.993380] [<ffffffff8020b62b>] ? system_call_after_swapgs+0x7b/0x80 > > Oh, joy - a page fault during a read() call triggers lock order > inversions on the mmap->sem. I don't think this can deadlock > (can't be page faulting in a vma that is being torn down), but > it's clear from the last trace that the VM has a mmap->sem > inversion problem with ->release vs ->read and page faults... > > Basically what we are seeing here in both cases is that the VM is > calling inode ->release or ->clear_inode methods with different high > level locks held. If the filesystem has to take the same locks in > these methods as it does in, say, ->read (like XFS does), then we > are guaranteed to get reports like this. AFAICT there's nothing we > can do from the filesystem perspective to prevent false positives like > this from being reported.... > > Cheers, > > Dave. > -- > Dave Chinner > Principal Engineer > SGI Australian Software Group > -- > To unsubscribe from this list: send the line "unsubscribe kernel-testers" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: 2.6.26-rc1: possible circular locking dependency with xfs filesystem 2008-05-15 17:45 ` Alexander Beregalov @ 2008-05-15 22:27 ` David Chinner 0 siblings, 0 replies; 5+ messages in thread From: David Chinner @ 2008-05-15 22:27 UTC (permalink / raw) To: Alexander Beregalov Cc: David Chinner, Kamalesh Babulal, pvp-lsts, kernel-testers, kernel list, Ingo Molnar, peterz, xfs On Thu, May 15, 2008 at 09:45:55PM +0400, Alexander Beregalov wrote: > 2008/5/12 David Chinner <dgc@sgi.com>: > > On Sun, May 11, 2008 at 09:18:07AM +0530, Kamalesh Babulal wrote: > >> Kamalesh Babulal wrote: > >> > Adding the cc to kernel-list, Ingo Molnar and Peter Zijlstra > >> > > >> > Alexander Beregalov wrote: > >> >> [ INFO: possible circular locking dependency detected ] > >> >> 2.6.26-rc1-00279-g28a4acb #13 > >> >> ------------------------------------------------------- > >> >> nfsd/3087 is trying to acquire lock: > >> >> (iprune_mutex){--..}, at: [<c016f947>] shrink_icache_memory+0x38/0x19b > >> >> > >> >> but task is already holding lock: > >> >> (&(&ip->i_iolock)->mr_lock){----}, at: [<c0210b83>] xfs_ilock+0xa2/0xd6 [snip] > > Oh, yeah, that. Direct inode reclaim through memory pressure. > > > > Effectively memory reclaim inverts locking order w.r.t. iprune_mutex > > when it recurses into the filesystem. False positive - can never > > cause a deadlock on XFS. Can't be solved from the XFS side of things > > without effectively turning off lockdep checking for xfs inode > > locking. > Yes, it is not a deadlock, but machine hangs for few seconds. > It still happens about once a day for me. Every kernel report looks > similar to the above. That hang is just memory reclaim running, I think you'll find. It can take some time for reclaim to find pages to use, and meanwhile everything in the machine will back up behind it.... Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group ^ permalink raw reply [flat|nested] 5+ messages in thread
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2008-05-10 17:46 ` 2.6.26-rc1: possible circular locking dependency Kamalesh Babulal
2008-05-11 3:48 ` 2.6.26-rc1: possible circular locking dependency with xfs filesystem Kamalesh Babulal
2008-05-11 23:10 ` David Chinner
2008-05-15 17:45 ` Alexander Beregalov
2008-05-15 22:27 ` David Chinner
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