On Thu 11-11-10 14:25:41, Valdis.Kletnieks@xxxxxx wrote: > On Tue, 09 Nov 2010 15:31:15 PST, akpm@xxxxxxxxxxxxxxxxxxxx said: > > The mm-of-the-moment snapshot 2010-11-09-15-31 has been uploaded to > > > > http://userweb.kernel.org/~akpm/mmotm/ > > Still seeing this just after quotas get turned on ext4. First seen in > 2.6.36-mmotm1022, but problem has apparently been there since > 2.6.36-rc5-mmotm0922 (oldest kernel I have lying around). Thanks for the report. In fact, it is a false positive caused by the fact that EXT4(inode)->i_data_sem for quota file inode would need a special locking class (or subclass) but does not have one. I'll have a look into implementing that sometime next week hopefully. Honza > The last few relevant commands from rc.sysinit: > > /sbin/quotaon -aug > dd if=/dev/urandom of=/var/lib/random-seed count=1 bs=512 <- this triggers the trace > > [ 48.967833] ======================================================= > [ 48.968162] [ INFO: possible circular locking dependency detected ] > [ 48.968411] 2.6.37-rc1-mmotm1109 #1 > [ 48.968553] ------------------------------------------------------- > [ 48.968592] dd/3253 is trying to acquire lock: > [ 48.968592] (&s->s_dquot.dqio_mutex){+.+...}, at: [<ffffffff81141b0a>] dquot_commit+0x26/0xda > [ 48.968592] > [ 48.968592] but task is already holding lock: > [ 48.968592] (&s->s_dquot.dqptr_sem){++++..}, at: [<ffffffff81143e70>] __dquot_free_space+0x66/0x16b > [ 48.968592] > [ 48.968592] which lock already depends on the new lock. > [ 48.968592] > [ 48.968592] > [ 48.968592] the existing dependency chain (in reverse order) is: > [ 48.968592] > [ 48.968592] -> #2 (&s->s_dquot.dqptr_sem){++++..}: > [ 48.968592] [<ffffffff8106b441>] lock_acquire+0x100/0x126 > [ 48.968592] [<ffffffff81565615>] down_read+0x42/0x51 > [ 48.968592] [<ffffffff81143e70>] __dquot_free_space+0x66/0x16b > [ 48.968592] [<ffffffff81199a70>] dquot_free_block+0x19/0x2a > [ 48.968592] [<ffffffff8119fc4f>] ext4_free_blocks+0x75b/0x810 > [ 48.968592] [<ffffffff81196f0f>] ext4_ext_truncate+0x3af/0x853 > [ 48.968592] [<ffffffff8117a02e>] ext4_truncate+0x98/0x51a > [ 48.968592] [<ffffffff810c46a4>] vmtruncate+0x3f/0x4b > [ 48.968592] [<ffffffff8117af55>] ext4_setattr+0x305/0x3a7 > [ 48.968592] [<ffffffff8110c6d9>] notify_change+0x1a1/0x2a1 > [ 48.968592] [<ffffffff810f49fa>] do_truncate+0x67/0x84 > [ 48.968592] [<ffffffff811029f5>] do_last+0x4ce/0x5b2 > [ 48.968592] [<ffffffff81102d21>] do_filp_open+0x248/0x64a > [ 48.968592] [<ffffffff810f5481>] do_sys_open+0x60/0xfb > [ 48.968592] [<ffffffff810f5537>] sys_open+0x1b/0x1d > [ 48.968592] [<ffffffff810027eb>] system_call_fastpath+0x16/0x1b > [ 48.968592] > [ 48.968592] -> #1 (&ei->i_data_sem){++++..}: > [ 48.968592] [<ffffffff8106b441>] lock_acquire+0x100/0x126 > [ 48.968592] [<ffffffff81565615>] down_read+0x42/0x51 > [ 48.968592] [<ffffffff81179383>] ext4_map_blocks+0x3e/0x20e > [ 48.968592] [<ffffffff81179e0b>] ext4_getblk+0x71/0x19b > [ 48.968592] [<ffffffff81179f46>] ext4_bread+0x11/0x61 > [ 48.968592] [<ffffffff8118b297>] ext4_quota_read+0x86/0xf0 > [ 48.968592] [<ffffffff81145131>] v2_read_header+0x1e/0x4f > [ 48.968592] [<ffffffff811455de>] v2_read_file_info+0x20/0x2ae > [ 48.968592] [<ffffffff81144423>] vfs_load_quota_inode+0x292/0x448 > [ 48.968592] [<ffffffff8114480e>] dquot_quota_on_path+0x4c/0x55 > [ 48.968592] [<ffffffff8118bc97>] ext4_quota_on+0x123/0x175 > [ 48.968592] [<ffffffff81146cf2>] do_quotactl+0x1d1/0x465 > [ 48.968592] [<ffffffff81147083>] sys_quotactl+0xfd/0x11a > [ 48.968592] [<ffffffff810027eb>] system_call_fastpath+0x16/0x1b > [ 48.968592] > [ 48.968592] -> #0 (&s->s_dquot.dqio_mutex){+.+...}: > [ 48.968592] [<ffffffff8106ac2d>] __lock_acquire+0xa4c/0xd4e > [ 48.968592] [<ffffffff8106b441>] lock_acquire+0x100/0x126 > [ 48.968592] [<ffffffff81564bbf>] __mutex_lock_common+0x5d/0x56c > [ 48.968592] [<ffffffff81565174>] mutex_lock_nested+0x34/0x39 > [ 48.968592] [<ffffffff81141b0a>] dquot_commit+0x26/0xda > [ 48.968592] [<ffffffff8118d622>] ext4_write_dquot+0x65/0x87 > [ 48.968592] [<ffffffff8118d682>] ext4_mark_dquot_dirty+0x3e/0x49 > [ 48.968592] [<ffffffff81141790>] mark_all_dquot_dirty+0x22/0x48 > [ 48.968592] [<ffffffff81143f43>] __dquot_free_space+0x139/0x16b > [ 48.968592] [<ffffffff81199a70>] dquot_free_block+0x19/0x2a > [ 48.968592] [<ffffffff8119fc4f>] ext4_free_blocks+0x75b/0x810 > [ 48.968592] [<ffffffff81196f0f>] ext4_ext_truncate+0x3af/0x853 > [ 48.968592] [<ffffffff8117a02e>] ext4_truncate+0x98/0x51a > [ 48.968592] [<ffffffff810c46a4>] vmtruncate+0x3f/0x4b > [ 48.968592] [<ffffffff8117af55>] ext4_setattr+0x305/0x3a7 > [ 48.968592] [<ffffffff8110c6d9>] notify_change+0x1a1/0x2a1 > [ 48.968592] [<ffffffff810f49fa>] do_truncate+0x67/0x84 > [ 48.968592] [<ffffffff811029f5>] do_last+0x4ce/0x5b2 > [ 48.968592] [<ffffffff81102d21>] do_filp_open+0x248/0x64a > [ 48.968592] [<ffffffff810f5481>] do_sys_open+0x60/0xfb > [ 48.968592] [<ffffffff810f5537>] sys_open+0x1b/0x1d > [ 48.968592] [<ffffffff810027eb>] system_call_fastpath+0x16/0x1b > [ 48.968592] > [ 48.968592] other info that might help us debug this: > [ 48.968592] > [ 49.458584] 5 locks held by dd/3253: > [ 49.458584] #0: (&sb->s_type->i_mutex_key#13){+.+.+.}, at: [<ffffffff810f49ee>] do_truncate+0x5b/0x84 > [ 49.458584] #1: (&sb->s_type->i_alloc_sem_key#5){+.+...}, at: [<ffffffff8110c6c1>] notify_change+0x189/0x2a1 > [ 49.458584] #2: (jbd2_handle){+.+...}, at: [<ffffffff811ad5b4>] start_this_handle+0x57a/0x605 > [ 49.458584] #3: (&ei->i_data_sem){++++..}, at: [<ffffffff81196bf1>] ext4_ext_truncate+0x91/0x853 > [ 49.458584] #4: (&s->s_dquot.dqptr_sem){++++..}, at: [<ffffffff81143e70>] __dquot_free_space+0x66/0x16b > [ 49.458584] > [ 49.458584] stack backtrace: > [ 49.458584] Pid: 3253, comm: dd Not tainted 2.6.37-rc1-mmotm1109 #1 > [ 49.458584] Call Trace: > [ 49.458584] [<ffffffff81069591>] print_circular_bug+0xa8/0xb7 > [ 49.458584] [<ffffffff8106ac2d>] __lock_acquire+0xa4c/0xd4e > [ 49.458584] [<ffffffff81141b0a>] ? dquot_commit+0x26/0xda > [ 49.458584] [<ffffffff8106b441>] lock_acquire+0x100/0x126 > [ 49.458584] [<ffffffff81141b0a>] ? dquot_commit+0x26/0xda > [ 49.458584] [<ffffffff81564bbf>] __mutex_lock_common+0x5d/0x56c > [ 49.458584] [<ffffffff81141b0a>] ? dquot_commit+0x26/0xda > [ 49.458584] [<ffffffff81141ef2>] ? dquot_mark_dquot_dirty+0x27/0x7a > [ 49.458584] [<ffffffff81141b0a>] ? dquot_commit+0x26/0xda > [ 49.458584] [<ffffffff81565174>] mutex_lock_nested+0x34/0x39 > [ 49.458584] [<ffffffff81141b0a>] dquot_commit+0x26/0xda > [ 49.458584] [<ffffffff8118d622>] ext4_write_dquot+0x65/0x87 > [ 49.458584] [<ffffffff8118d682>] ext4_mark_dquot_dirty+0x3e/0x49 > [ 49.458584] [<ffffffff81141790>] mark_all_dquot_dirty+0x22/0x48 > [ 49.458584] [<ffffffff81143f43>] __dquot_free_space+0x139/0x16b > [ 49.458584] [<ffffffff81199a70>] dquot_free_block+0x19/0x2a > [ 49.458584] [<ffffffff8119fc4f>] ext4_free_blocks+0x75b/0x810 > [ 49.458584] [<ffffffff811ada1d>] ? jbd2_journal_extend+0x5d/0xb8 > [ 49.458584] [<ffffffff81196f0f>] ext4_ext_truncate+0x3af/0x853 > [ 49.458584] [<ffffffff810a5759>] ? trace_preempt_on+0x15/0x28 > [ 49.458584] [<ffffffff810d63f6>] ? unmap_mapping_range+0x279/0x288 > [ 49.458584] [<ffffffff8117a02e>] ext4_truncate+0x98/0x51a > [ 49.458584] [<ffffffff810d63f6>] ? unmap_mapping_range+0x279/0x288 > [ 49.458584] [<ffffffff8106b861>] ? trace_hardirqs_on_caller+0x117/0x13b > [ 49.458584] [<ffffffff8106b892>] ? trace_hardirqs_on+0xd/0xf > [ 49.458584] [<ffffffff810c46a4>] vmtruncate+0x3f/0x4b > [ 49.458584] [<ffffffff8117af55>] ext4_setattr+0x305/0x3a7 > [ 49.458584] [<ffffffff8110c6d9>] notify_change+0x1a1/0x2a1 > [ 49.458584] [<ffffffff810f49fa>] do_truncate+0x67/0x84 > [ 49.458584] [<ffffffff810ff92d>] ? get_write_access+0x49/0x50 > [ 49.458584] [<ffffffff81566794>] ? _raw_spin_unlock+0x30/0x69 > [ 49.458584] [<ffffffff8156a040>] ? sub_preempt_count+0x35/0x48 > [ 49.458584] [<ffffffff811e0833>] ? security_path_truncate+0x48/0x4d > [ 49.458584] [<ffffffff811029f5>] do_last+0x4ce/0x5b2 > [ 49.458584] [<ffffffff81102d21>] do_filp_open+0x248/0x64a > [ 49.458584] [<ffffffff810a5759>] ? trace_preempt_on+0x15/0x28 > [ 49.458584] [<ffffffff8110d8ce>] ? alloc_fd+0x17c/0x18e > [ 49.458584] [<ffffffff81566794>] ? _raw_spin_unlock+0x30/0x69 > [ 49.458584] [<ffffffff8156a040>] ? sub_preempt_count+0x35/0x48 > [ 49.458584] [<ffffffff8110d8ce>] ? alloc_fd+0x17c/0x18e > [ 49.458584] [<ffffffff810f5481>] do_sys_open+0x60/0xfb > [ 49.458584] [<ffffffff81565fde>] ? trace_hardirqs_on_thunk+0x3a/0x3f > [ 49.458584] [<ffffffff810f5537>] sys_open+0x1b/0x1d > [ 49.458584] [<ffffffff810027eb>] system_call_fastpath+0x16/0x1b > > -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
