Possible irq lock inversion dependency detected in JBD
Hello,
During testing I had the below trace from lockdep. After some googling seems it wasn't reported. The complete trace attached, it's almost 800K uncompressed.
=========================================================
[ INFO: possible irq lock inversion dependency detected ] 2.6.31-scst-dbg #3
---------------------------------------------------------
kswapd0/290 just changed the state of lock:
(jbd_handle){+.+.-.}, at: [<7826a6fa>] journal_start+0xd4/0x13a
but this lock took another, RECLAIM_FS-unsafe lock in the past:
(&type->s_lock_key){+.+.+.}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
no locks held by kswapd0/290.
the first lock's dependencies:
-> (jbd_handle){+.+.-.} ops: 0 {
HARDIRQ-ON-W at:
[<781719d9>] __lock_acquire+0x4e0/0x102d
[<7817260e>] lock_acquire+0xe8/0x127
[<7826a725>] journal_start+0xff/0x13a
[<78261d2e>] ext3_journal_start_sb+0x39/0x70
[<7825d7d5>] ext3_create+0x81/0x10b
[<781ffbbc>] vfs_create+0xa9/0xbd
[<7820296f>] do_filp_open+0x862/0x941
[<781f2943>] do_sys_open+0x7e/0x13a
[<781f2a80>] sys_open+0x33/0x4c
[<7810328b>] sysenter_do_call+0x12/0x32
[<ffffffff>] 0xffffffff
SOFTIRQ-ON-W at:
[<781719ff>] __lock_acquire+0x506/0x102d
[<7817260e>] lock_acquire+0xe8/0x127
[<7826a725>] journal_start+0xff/0x13a
[<78261d2e>] ext3_journal_start_sb+0x39/0x70
[<7825d7d5>] ext3_create+0x81/0x10b
[<781ffbbc>] vfs_create+0xa9/0xbd
[<7820296f>] do_filp_open+0x862/0x941
[<781f2943>] do_sys_open+0x7e/0x13a
[<781f2a80>] sys_open+0x33/0x4c
[<7810328b>] sysenter_do_call+0x12/0x32
[<ffffffff>] 0xffffffff
IN-RECLAIM_FS-W at:
[<78171876>] __lock_acquire+0x37d/0x102d
[<7817260e>] lock_acquire+0xe8/0x127
[<7826a725>] journal_start+0xff/0x13a
[<78261d2e>] ext3_journal_start_sb+0x39/0x70
[<78256ffb>] ext3_ordered_writepage+0xb8/0x1dc
[<781ce157>] shrink_page_list+0x64a/0x7cb
[<781ce966>] shrink_zone+0x68e/0xa6f
[<781cf341>] kswapd+0x5fa/0x625
[<7815ac79>] kthread+0x84/0x8d
[<78103f57>] kernel_thread_helper+0x7/0x10
[<ffffffff>] 0xffffffff
INITIAL USE at:
[<78171677>] __lock_acquire+0x17e/0x102d
[<7817260e>] lock_acquire+0xe8/0x127
[<7826a725>] journal_start+0xff/0x13a
[<78261d2e>] ext3_journal_start_sb+0x39/0x70
[<7825d7d5>] ext3_create+0x81/0x10b
[<781ffbbc>] vfs_create+0xa9/0xbd
[<7820296f>] do_filp_open+0x862/0x941
[<781f2943>] do_sys_open+0x7e/0x13a
[<781f2a80>] sys_open+0x33/0x4c
[<7810328b>] sysenter_do_call+0x12/0x32
[<ffffffff>] 0xffffffff
}
... key at: [<7ad3e6d4>] jbd_handle_key+0x0/0x8
-> (inode_lock){+.+.-.} ops: 0 {
HARDIRQ-ON-W at:
[<781719d9>] __lock_acquire+0x4e0/0x102d
[<7817260e>] lock_acquire+0xe8/0x127
[<7849aca4>] _spin_lock+0x4d/0x8e
[<7820afe4>] ifind_fast+0x29/0xa4
[<7820b310>] iget_locked+0x3d/0x148
[<7824da34>] sysfs_get_inode+0x27/0x1e1
[<7825077e>] sysfs_fill_super+0x59/0xdb
[<781f7b30>] get_sb_single+0x9b/0xc0
[<7825070b>] sysfs_get_sb+0x2e/0x48
[<781f68af>] vfs_kern_mount+0x51/0xab
[<781f692f>] kern_mount_data+0x26/0x3c
[<78657314>] sysfs_init+0x8f/0xc8
[<78655e07>] mnt_init+0x97/0x1b0
[<786558ab>] vfs_caches_init+0xb1/0x155
[<78638b03>] start_kernel+0x319/0x40a
[<78638085>] __init_begin+0x85/0xb0
[<ffffffff>] 0xffffffff
SOFTIRQ-ON-W at:
[<781719ff>] __lock_acquire+0x506/0x102d
[<7817260e>] lock_acquire+0xe8/0x127
[<7849aca4>] _spin_lock+0x4d/0x8e
[<7820afe4>] ifind_fast+0x29/0xa4
[<7820b310>] iget_locked+0x3d/0x148
[<7824da34>] sysfs_get_inode+0x27/0x1e1
[<7825077e>] sysfs_fill_super+0x59/0xdb
[<781f7b30>] get_sb_single+0x9b/0xc0
[<7825070b>] sysfs_get_sb+0x2e/0x48
[<781f68af>] vfs_kern_mount+0x51/0xab
[<781f692f>] kern_mount_data+0x26/0x3c
[<78657314>] sysfs_init+0x8f/0xc8
[<78655e07>] mnt_init+0x97/0x1b0
[<786558ab>] vfs_caches_init+0xb1/0x155
[<78638b03>] start_kernel+0x319/0x40a
[<78638085>] __init_begin+0x85/0xb0
[<ffffffff>] 0xffffffff
IN-RECLAIM_FS-W at:
[<78171876>] __lock_acquire+0x37d/0x102d
[<7817260e>] lock_acquire+0xe8/0x127
[<7849aca4>] _spin_lock+0x4d/0x8e
[<782a0bcf>] _atomic_dec_and_lock+0x63/0x84
[<78209b05>] iput+0x33/0x75
[<7825006f>] sysfs_d_iput+0x39/0x57
[<78206d24>] dentry_iput+0x6d/0xfc
[<78206eb5>] d_kill+0x30/0x5e
[<782070f5>] __shrink_dcache_sb+0x212/0x2e7
[<78207308>] shrink_dcache_memory+0x13e/0x1b6
[<781cd543>] shrink_slab+0x146/0x1b8
[<781cf248>] kswapd+0x501/0x625
[<7815ac79>] kthread+0x84/0x8d
[<78103f57>] kernel_thread_helper+0x7/0x10
[<ffffffff>] 0xffffffff
INITIAL USE at:
[<78171677>] __lock_acquire+0x17e/0x102d
[<7817260e>] lock_acquire+0xe8/0x127
[<7849aca4>] _spin_lock+0x4d/0x8e
[<7820afe4>] ifind_fast+0x29/0xa4
[<7820b310>] iget_locked+0x3d/0x148
[<7824da34>] sysfs_get_inode+0x27/0x1e1
[<7825077e>] sysfs_fill_super+0x59/0xdb
[<781f7b30>] get_sb_single+0x9b/0xc0
[<7825070b>] sysfs_get_sb+0x2e/0x48
[<781f68af>] vfs_kern_mount+0x51/0xab
[<781f692f>] kern_mount_data+0x26/0x3c
[<78657314>] sysfs_init+0x8f/0xc8
[<78655e07>] mnt_init+0x97/0x1b0
[<786558ab>] vfs_caches_init+0xb1/0x155
[<78638b03>] start_kernel+0x319/0x40a
[<78638085>] __init_begin+0x85/0xb0
[<ffffffff>] 0xffffffff
}...
stack backtrace: Pid: 290, comm: kswapd0 Not tainted 2.6.31-scst-dbg #3 Call Trace: [<78497768>] ? printk+0x28/0x40 [<7816f9e1>] print_irq_inversion_bug+0x123/0x13a [<7816fd20>] check_usage_forwards+0x65/0xb0 [<7817056d>] mark_lock+0x18f/0x3b3 [<7816fcbb>] ? check_usage_forwards+0x0/0xb0 [<78171876>] __lock_acquire+0x37d/0x102d [<7816ee05>] ? put_lock_stats+0x18/0x45 [<78170313>] ? lock_release_holdtime+0xaa/0x175 [<7826a6fa>] ? journal_start+0xd4/0x13a [<7849e1ea>] ? sub_preempt_count+0x9a/0xd3 [<7849b42f>] ? _spin_unlock+0x3a/0x6d [<7826a43a>] ? start_this_handle+0x313/0x41a [<7826a6fa>] ? journal_start+0xd4/0x13a [<7817260e>] lock_acquire+0xe8/0x127 [<7826a6fa>] ? journal_start+0xd4/0x13a [<7826a725>] journal_start+0xff/0x13a [<7826a6fa>] ? journal_start+0xd4/0x13a [<78261d2e>] ext3_journal_start_sb+0x39/0x70 [<78256ffb>] ext3_ordered_writepage+0xb8/0x1dc [<78170b60>] ? trace_hardirqs_on+0x19/0x2e [<781ce157>] shrink_page_list+0x64a/0x7cb [<781ce966>] shrink_zone+0x68e/0xa6f [<7815fe6f>] ? up_read+0x29/0x5a [<781cf341>] kswapd+0x5fa/0x625 [<781cc7ed>] ? isolate_pages_global+0x0/0x1fa [<7815b03d>] ? autoremove_wake_function+0x0/0x5b [<781ced47>] ? kswapd+0x0/0x625 [<7815ac79>] kthread+0x84/0x8d [<7815abf5>] ? kthread+0x0/0x8d [<78103f57>] kernel_thread_helper+0x7/0x10
Vlad
Hello,
Quoted 12 lines
During testing I had the below trace from lockdep. After some googling seems it wasn't reported. The complete trace attached, it's almost 800K uncompressed.
=========================================================
[ INFO: possible irq lock inversion dependency detected ] 2.6.31-scst-dbg #3
---------------------------------------------------------
kswapd0/290 just changed the state of lock:
(jbd_handle){+.+.-.}, at: [<7826a6fa>]journal_start+0xd4/0x13a
but this lock took another, RECLAIM_FS-unsafe lock in the past:
(&type->s_lock_key){+.+.+.}
Quoted 5 lines
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
no locks held by kswapd0/290.
Thanks for the report. If I'm reading the lockdep messages right, it
complains that page reclaim can be run with sb->s_lock held but we also start a transaction in the page reclaim path and we take sb->s_lock after starting a transaction in some paths.
The warning seems to be false positive to me since we don't really
acquire sb->s_lock in the reclaim path. It would be nice if we could get this sorted out but I don't see an easy way out of this...
Honza
Signature · 2 lines
Jan Kara <[email protected]> SuSE CR Labs
Quoted 19 lines · Jan Kara, on 12/08/2009 06:13 PM wrote:
Hello,
Quoted 12 lines
During testing I had the below trace from lockdep. After some googling seems it wasn't reported. The complete trace attached, it's almost 800K uncompressed.
=========================================================
[ INFO: possible irq lock inversion dependency detected ] 2.6.31-scst-dbg #3
---------------------------------------------------------
kswapd0/290 just changed the state of lock:
(jbd_handle){+.+.-.}, at: [<7826a6fa>]journal_start+0xd4/0x13a
but this lock took another, RECLAIM_FS-unsafe lock in the past:
(&type->s_lock_key){+.+.+.}Quoted 5 lines
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
no locks held by kswapd0/290.
Quoted 7 lines
Thanks for the report. If I'm reading the lockdep messages right, it
complains that page reclaim can be run withsb->s_lockheld but we also start a transaction in the page reclaim path and we takesb->s_lockafter starting a transaction in some paths.
The warning seems to be false positive to me since we don't really
acquiresb->s_lockin the reclaim path. It would be nice if we could get this sorted out but I don't see an easy way out of this...
In my experience lockdep has never complained about acquiring a lock, where it had never been acquired, so I would rather take the complaint seriously. However, a false possitive can be if the same lock acquired for another object. I have swap as a file on a different ext3 partition.
Quoted 1 line
From other side, during further tests I yesterday had the following lockup.
It seems to be somehow related. 2.6.29 works just fine.
[ 8298.566616] BUG: spinlock lockup on CPU#0, xfsbufd/2726, f6b52e58 [ 8298.566632] NMI backtrace for cpu 1 [ 8298.566632] ------------[ cut here ]------------ [ 8298.566632] WARNING: at kernel/sched.c:5175 add_preempt_count+0x82/0xdd() [ 8298.566632] Hardware name: X5DPA [ 8298.566632] Modules linked in: iscsi_scst scst_user scst_disk scst_vdisk scst libcrc32c cryptomgr aead pcompress crypto_blkcipher crc32c crypto_hash crypto_algapi tcp_highspeed scsi_debug w83627hf hwmon_vid adm1021 binfmt_misc xfs exportfs dm_mirror dm_region_hash dm_log dm_mod pci_slot floppy uhci_hcd sg e1000 ata_generic pcspkr i2c_i801 libata i2c_core e7xxx_edac parport_pc parport [last unloaded: scst] [ 8298.566632] Pid: 14244, comm: vdisk_fileid2_7 Not tainted 2.6.31-scst-dbg #3 [ 8298.566632] Call Trace: [ 8298.566632] [<78497768>] ? printk+0x28/0x40 [ 8298.566632] [<7849e2a5>] ? add_preempt_count+0x82/0xdd [ 8298.566632] [<78140225>] warn_slowpath_common+0x7e/0xda [ 8298.566632] [<7849e2a5>] ? add_preempt_count+0x82/0xdd [ 8298.566632] [<781402a7>] warn_slowpath_null+0x26/0x3c [ 8298.566632] [<7849e2a5>] add_preempt_count+0x82/0xdd [ 8298.566632] [<7849ae42>] _spin_lock_irqsave+0x2d/0x9a [ 8298.566632] [<78160551>] down_trylock+0x21/0x54 [ 8298.566632] [<781407f5>] try_acquire_console_sem+0x20/0x6e [ 8298.566632] [<78140fe1>] vprintk+0x114/0x427 [ 8298.566632] [<78497768>] printk+0x28/0x40 [ 8298.566632] [<7849cef8>] nmi_watchdog_tick+0x1e3/0x20b [ 8298.566632] [<7849c03d>] do_nmi+0x18e/0x33a [ 8298.566632] [<7849bcc4>] nmi_stack_correct+0x2f/0x34 [ 8298.566632] [<781700e0>] ? check_irq_usage+0x31/0xda [ 8298.566632] [<781586c6>] ? __kernel_text_address+0x21/0x80 [ 8298.566632] [<781070c3>] print_context_stack+0x82/0x13f [ 8298.566632] [<78105e75>] dump_trace+0xa1/0xfb [ 8298.566632] [<7810e0e2>] save_stack_trace+0x3b/0x68 [ 8298.566632] [<782c1fb9>] dma_entry_alloc+0x79/0xb7 [ 8298.566632] [<782c33bb>] debug_dma_map_sg+0x4a/0x167 [ 8298.566632] [<78357de5>] scsi_dma_map+0xc9/0x104 [ 8298.566632] [<78372c98>] ahd_linux_queue+0x48/0x39a [ 8298.566632] [<7849ae94>] ? _spin_lock_irqsave+0x7f/0x9a [ 8298.566632] [<7834f218>] ? scsi_dispatch_cmd+0x106/0x275 [ 8298.566632] [<7834f25d>] scsi_dispatch_cmd+0x14b/0x275 [ 8298.566632] [<7849e1ea>] ? sub_preempt_count+0x9a/0xd3 [ 8298.566632] [<78355e0a>] scsi_request_fn+0x398/0x4de [ 8298.566632] [<7828acc0>] __generic_unplug_device+0x3e/0x5b [ 8298.566632] [<7828343d>] elv_insert+0x208/0x272 [ 8298.566632] [<781928b4>] ? __rcu_read_unlock+0x9b/0xac [ 8298.566632] [<78283520>] __elv_add_request+0x79/0xc7 [ 8298.566632] [<7828f242>] __make_request+0x12d/0x412 [ 8298.566632] [<7828e116>] generic_make_request+0x42c/0x5f8 [ 8298.566632] [<7849e1ea>] ? sub_preempt_count+0x9a/0xd3 [ 8298.566632] [<78170b60>] ? trace_hardirqs_on+0x19/0x2e [ 8298.566632] [<781c3db7>] ? mempool_alloc_slab+0x22/0x38 [ 8298.566632] [<781c3db7>] ? mempool_alloc_slab+0x22/0x38 [ 8298.566632] [<781c3db7>] ? mempool_alloc_slab+0x22/0x38 [ 8298.566632] [<7828f9c6>] submit_bio+0x9b/0x155 [ 8298.566632] [<78219f94>] submit_bh+0x106/0x14a [ 8298.566632] [<7821c0d8>] __block_write_full_page+0x222/0x394 [ 8298.566632] [<7821c73d>] ? end_buffer_async_write+0x0/0x238 [ 8298.566632] [<7821ce27>] block_write_full_page_endio+0x133/0x13d [ 8298.566632] [<7821c73d>] ? end_buffer_async_write+0x0/0x238 [ 8298.566632] [<7821c73d>] ? end_buffer_async_write+0x0/0x238 [ 8298.566632] [<7821ce55>] block_write_full_page+0x24/0x3c [ 8298.566632] [<7821c73d>] ? end_buffer_async_write+0x0/0x238 [ 8298.566632] [<78257228>] ext3_writeback_writepage+0x109/0x13f [ 8298.566632] [<782565c6>] ? buffer_unmapped+0x0/0x34 [ 8298.566632] [<781ce157>] shrink_page_list+0x64a/0x7cb [ 8298.566632] [<7849780b>] ? io_schedule_timeout+0x8b/0xc0 [ 8298.566632] [<781d7d49>] ? congestion_wait+0x72/0x8d [ 8298.566632] [<781ced02>] shrink_zone+0xa2a/0xa6f [ 8298.566632] [<781cd56e>] ? shrink_slab+0x171/0x1b8 [ 8298.566632] [<7815fe6f>] ? up_read+0x29/0x5a [ 8298.566632] [<781cf57e>] try_to_free_pages+0x212/0x364 [ 8298.566632] [<781cc7ed>] ? isolate_pages_global+0x0/0x1fa [ 8298.566632] [<781c7acd>] __alloc_pages_nodemask+0x3bb/0x5db [ 8298.566632] [<781707fb>] ? mark_held_locks+0x6a/0x9a [ 8298.566632] [<781ee2c6>] __slab_alloc+0x1b9/0x5d3 [ 8298.566632] [<783d6db9>] ? __alloc_skb+0x39/0x13b [ 8298.566632] [<781ee873>] kmem_cache_alloc+0x193/0x19f [ 8298.566632] [<783d6db9>] ? __alloc_skb+0x39/0x13b [ 8298.566632] [<783d6db9>] ? __alloc_skb+0x39/0x13b [ 8298.566632] [<783d6db9>] __alloc_skb+0x39/0x13b [ 8298.566632] [<783d2ec7>] ? lock_sock_nested+0xd5/0xee [ 8298.566632] [<784144d1>] sk_stream_alloc_skb+0x3f/0xf0 [ 8298.566632] [<78417007>] tcp_sendmsg+0x402/0x99b [ 8298.566632] [<781099cf>] ? sched_clock+0x1e/0x80 [ 8298.566632] [<7840dfef>] ? ip_finish_output+0x14c/0x310 [ 8298.566632] [<783cf1f8>] sock_aio_write+0x10f/0x129 [ 8298.566632] [<781099cf>] ? sched_clock+0x1e/0x80 [ 8298.566632] [<783cf0e9>] ? sock_aio_write+0x0/0x129 [ 8298.566632] [<781f46d8>] do_sync_readv_writev+0xdb/0x125 [ 8298.566632] [<7815b03d>] ? autoremove_wake_function+0x0/0x5b [ 8298.566632] [<781f44ee>] ? rw_copy_check_uvector+0x80/0x12f [ 8298.566632] [<781f5692>] do_readv_writev+0xb8/0x229 [ 8298.566632] [<783cf0e9>] ? sock_aio_write+0x0/0x129 [ 8298.566632] [<7814811a>] ? local_bh_enable_ip+0x75/0xfb [ 8298.566632] [<78170af9>] ? trace_hardirqs_on_caller+0x13a/0x188 [ 8298.566632] [<ffde4a78>] ? write_data+0xce/0xabf [iscsi_scst] [ 8298.566632] [<781f5862>] vfs_writev+0x5f/0x77 [ 8298.566632] [<ffde4b48>] write_data+0x19e/0xabf [iscsi_scst] [ 8298.566632] [<7816ee05>] ? put_lock_stats+0x18/0x45 [ 8298.566632] [<78170313>] ? lock_release_holdtime+0xaa/0x175 [ 8298.566632] [<ffddd309>] ? cmnd_set_sn+0x6f/0xa6 [iscsi_scst] [ 8298.566632] [<ffde5b3f>] iscsi_do_send+0x2a/0x63 [iscsi_scst] [ 8298.566632] [<ffde5f2e>] iscsi_send+0x1ca/0x359 [iscsi_scst] [ 8298.566632] [<7814811a>] ? local_bh_enable_ip+0x75/0xfb [ 8298.566632] [<ffddd542>] iscsi_try_local_processing+0x15c/0x1bd [iscsi_scst] [ 8298.566632] [<ffde133f>] iscsi_xmit_response+0x197/0x328 [iscsi_scst] [ 8298.566632] [<7816ee05>] ? put_lock_stats+0x18/0x45 [ 8298.566632] [<78170313>] ? lock_release_holdtime+0xaa/0x175 [ 8298.566632] [<f90ef48c>] scst_xmit_response+0x139/0x4ab [scst] [ 8298.566632] [<f90f12e5>] ? scst_pre_xmit_response+0xb0/0x274 [scst] [ 8298.566632] [<78170b60>] ? trace_hardirqs_on+0x19/0x2e [ 8298.566632] [<f90f356a>] scst_process_active_cmd+0x176/0x536 [scst] [ 8298.566632] [<f90ed88d>] ? scst_cmd_atomic+0x62/0xa3 [scst] [ 8298.566632] [<f90f3fc5>] scst_process_redirect_cmd+0x1b0/0x298 [scst] [ 8298.566632] [<f90f42b8>] scst_cmd_done_local+0xff/0x257 [scst] [ 8298.566632] [<f8e3447e>] vdisk_do_job+0x1f9/0xae2 [scst_vdisk] [ 8298.566632] [<78133a93>] ? finish_task_switch+0x69/0x105 [ 8298.566632] [<f90ed88d>] ? scst_cmd_atomic+0x62/0xa3 [scst] [ 8298.566632] [<f90f2a73>] scst_do_real_exec+0xbb/0x3fa [scst] [ 8298.566632] [<f90f2781>] ? scst_do_local_exec+0x143/0x23a [scst] [ 8298.566632] [<f90f2e82>] scst_exec+0xd0/0x25e [scst] [ 8298.566632] [<ffddd3a5>] ? scst_cmd_atomic+0x65/0xa6 [iscsi_scst] [ 8298.566632] [<f90f3150>] scst_send_for_exec+0x140/0x2a5 [scst] [ 8298.566632] [<f90ed67c>] ? scst_tgt_pre_exec+0x77/0x226 [scst] [ 8298.566632] [<f90f37a9>] scst_process_active_cmd+0x3b5/0x536 [scst] [ 8298.566632] [<7849e1ea>] ? sub_preempt_count+0x9a/0xd3 [ 8298.566632] [<f90f39ba>] scst_do_job_active+0x90/0x158 [scst] [ 8298.566632] [<f90f3c22>] scst_cmd_thread+0xc1/0x279 [scst] [ 8298.566632] [<7849b855>] ? _spin_unlock_irqrestore+0x8b/0x90 [ 8298.566632] [<7813b430>] ? default_wake_function+0x0/0x3d [ 8298.566632] [<f90f3b61>] ? scst_cmd_thread+0x0/0x279 [scst] [ 8298.566632] [<7815ac79>] kthread+0x84/0x8d [ 8298.566632] [<7815abf5>] ? kthread+0x0/0x8d [ 8298.566632] [<78103f57>] kernel_thread_helper+0x7/0x10
Thanks,
Vlad
Quoted 28 lines · Vladislav Bolkhovitin
Quoted 19 lines · Jan Kara, on 12/08/2009 06:13 PM wrote:
Hello,
Quoted 12 lines
During testing I had the below trace from lockdep. After some googling seems it wasn't reported. The complete trace attached, it's almost 800K uncompressed.
=========================================================
[ INFO: possible irq lock inversion dependency detected ] 2.6.31-scst-dbg #3
---------------------------------------------------------
kswapd0/290 just changed the state of lock:
(jbd_handle){+.+.-.}, at: [<7826a6fa>]journal_start+0xd4/0x13a
but this lock took another, RECLAIM_FS-unsafe lock in the past:
(&type->s_lock_key){+.+.+.}Quoted 5 lines
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
no locks held by kswapd0/290.Quoted 7 lines
Thanks for the report. If I'm reading the lockdep messages right, it
complains that page reclaim can be run withsb->s_lockheld but we also start a transaction in the page reclaim path and we takesb->s_lockafter starting a transaction in some paths.
The warning seems to be false positive to me since we don't really
acquiresb->s_lockin the reclaim path. It would be nice if we could get this sorted out but I don't see an easy way out of this...
Quoted 4 lines
In my experience lockdep has never complained about acquiring a lock, where it had never been acquired, so I would rather take the complaint seriously. However, a false possitive can be if the same lock acquired for another object. I have swap as a file on a different ext3 partition.
Well, I take lockdep warning seriously. It's just that lockdep
establishes following lock dependencies:
1) transaction start -> lock_super
- happens only during unlink, truncate, filesystem resize, sys_write
2) lock_super -> page reclaim
- happens during mount / remount
3) page reclaim -> transaction start
and reports a possible problem. But it follows from the above thatlock_super actually does not happen from the page reclaim path because there we just start a transaction to write inode or allocate blocks to a file. So I agree the locking is kind of convoluted but I see no real problem there...
Quoted 2 lines
From other side, during further tests I yesterday had the following lockup. It seems to be somehow related. 2.6.29 works just fine.
Looks like a bug in the scsi stack... adding linux-scsi to CC.
Honza
Quoted 132 lines
[ 8298.566616] BUG: spinlock lockup on CPU#0, xfsbufd/2726, f6b52e58 [ 8298.566632] NMI backtrace for cpu 1 [ 8298.566632] ------------[ cut here ]------------ [ 8298.566632] WARNING: at kernel/sched.c:5175 add_preempt_count+0x82/0xdd() [ 8298.566632] Hardware name: X5DPA [ 8298.566632] Modules linked in: iscsi_scst scst_user scst_disk scst_vdisk scst libcrc32c cryptomgr aead pcompress crypto_blkcipher crc32c crypto_hash crypto_algapi tcp_highspeed scsi_debug w83627hf hwmon_vid adm1021 binfmt_misc xfs exportfs dm_mirror dm_region_hash dm_log dm_mod pci_slot floppy uhci_hcd sg e1000 ata_generic pcspkr i2c_i801 libata i2c_core e7xxx_edac parport_pc parport [last unloaded: scst] [ 8298.566632] Pid: 14244, comm: vdisk_fileid2_7 Not tainted 2.6.31-scst-dbg #3 [ 8298.566632] Call Trace: [ 8298.566632] [<78497768>] ? printk+0x28/0x40 [ 8298.566632] [<7849e2a5>] ? add_preempt_count+0x82/0xdd [ 8298.566632] [<78140225>] warn_slowpath_common+0x7e/0xda [ 8298.566632] [<7849e2a5>] ? add_preempt_count+0x82/0xdd [ 8298.566632] [<781402a7>] warn_slowpath_null+0x26/0x3c [ 8298.566632] [<7849e2a5>] add_preempt_count+0x82/0xdd [ 8298.566632] [<7849ae42>] _spin_lock_irqsave+0x2d/0x9a [ 8298.566632] [<78160551>] down_trylock+0x21/0x54 [ 8298.566632] [<781407f5>] try_acquire_console_sem+0x20/0x6e [ 8298.566632] [<78140fe1>] vprintk+0x114/0x427 [ 8298.566632] [<78497768>] printk+0x28/0x40 [ 8298.566632] [<7849cef8>] nmi_watchdog_tick+0x1e3/0x20b [ 8298.566632] [<7849c03d>] do_nmi+0x18e/0x33a [ 8298.566632] [<7849bcc4>] nmi_stack_correct+0x2f/0x34 [ 8298.566632] [<781700e0>] ? check_irq_usage+0x31/0xda [ 8298.566632] [<781586c6>] ? __kernel_text_address+0x21/0x80 [ 8298.566632] [<781070c3>] print_context_stack+0x82/0x13f [ 8298.566632] [<78105e75>] dump_trace+0xa1/0xfb [ 8298.566632] [<7810e0e2>] save_stack_trace+0x3b/0x68 [ 8298.566632] [<782c1fb9>] dma_entry_alloc+0x79/0xb7 [ 8298.566632] [<782c33bb>] debug_dma_map_sg+0x4a/0x167 [ 8298.566632] [<78357de5>] scsi_dma_map+0xc9/0x104 [ 8298.566632] [<78372c98>] ahd_linux_queue+0x48/0x39a [ 8298.566632] [<7849ae94>] ? _spin_lock_irqsave+0x7f/0x9a [ 8298.566632] [<7834f218>] ? scsi_dispatch_cmd+0x106/0x275 [ 8298.566632] [<7834f25d>] scsi_dispatch_cmd+0x14b/0x275 [ 8298.566632] [<7849e1ea>] ? sub_preempt_count+0x9a/0xd3 [ 8298.566632] [<78355e0a>] scsi_request_fn+0x398/0x4de [ 8298.566632] [<7828acc0>] __generic_unplug_device+0x3e/0x5b [ 8298.566632] [<7828343d>] elv_insert+0x208/0x272 [ 8298.566632] [<781928b4>] ? __rcu_read_unlock+0x9b/0xac [ 8298.566632] [<78283520>] __elv_add_request+0x79/0xc7 [ 8298.566632] [<7828f242>] __make_request+0x12d/0x412 [ 8298.566632] [<7828e116>] generic_make_request+0x42c/0x5f8 [ 8298.566632] [<7849e1ea>] ? sub_preempt_count+0x9a/0xd3 [ 8298.566632] [<78170b60>] ? trace_hardirqs_on+0x19/0x2e [ 8298.566632] [<781c3db7>] ? mempool_alloc_slab+0x22/0x38 [ 8298.566632] [<781c3db7>] ? mempool_alloc_slab+0x22/0x38 [ 8298.566632] [<781c3db7>] ? mempool_alloc_slab+0x22/0x38 [ 8298.566632] [<7828f9c6>] submit_bio+0x9b/0x155 [ 8298.566632] [<78219f94>] submit_bh+0x106/0x14a [ 8298.566632] [<7821c0d8>] __block_write_full_page+0x222/0x394 [ 8298.566632] [<7821c73d>] ? end_buffer_async_write+0x0/0x238 [ 8298.566632] [<7821ce27>] block_write_full_page_endio+0x133/0x13d [ 8298.566632] [<7821c73d>] ? end_buffer_async_write+0x0/0x238 [ 8298.566632] [<7821c73d>] ? end_buffer_async_write+0x0/0x238 [ 8298.566632] [<7821ce55>] block_write_full_page+0x24/0x3c [ 8298.566632] [<7821c73d>] ? end_buffer_async_write+0x0/0x238 [ 8298.566632] [<78257228>] ext3_writeback_writepage+0x109/0x13f [ 8298.566632] [<782565c6>] ? buffer_unmapped+0x0/0x34 [ 8298.566632] [<781ce157>] shrink_page_list+0x64a/0x7cb [ 8298.566632] [<7849780b>] ? io_schedule_timeout+0x8b/0xc0 [ 8298.566632] [<781d7d49>] ? congestion_wait+0x72/0x8d [ 8298.566632] [<781ced02>] shrink_zone+0xa2a/0xa6f [ 8298.566632] [<781cd56e>] ? shrink_slab+0x171/0x1b8 [ 8298.566632] [<7815fe6f>] ? up_read+0x29/0x5a [ 8298.566632] [<781cf57e>] try_to_free_pages+0x212/0x364 [ 8298.566632] [<781cc7ed>] ? isolate_pages_global+0x0/0x1fa [ 8298.566632] [<781c7acd>] __alloc_pages_nodemask+0x3bb/0x5db [ 8298.566632] [<781707fb>] ? mark_held_locks+0x6a/0x9a [ 8298.566632] [<781ee2c6>] __slab_alloc+0x1b9/0x5d3 [ 8298.566632] [<783d6db9>] ? __alloc_skb+0x39/0x13b [ 8298.566632] [<781ee873>] kmem_cache_alloc+0x193/0x19f [ 8298.566632] [<783d6db9>] ? __alloc_skb+0x39/0x13b [ 8298.566632] [<783d6db9>] ? __alloc_skb+0x39/0x13b [ 8298.566632] [<783d6db9>] __alloc_skb+0x39/0x13b [ 8298.566632] [<783d2ec7>] ? lock_sock_nested+0xd5/0xee [ 8298.566632] [<784144d1>] sk_stream_alloc_skb+0x3f/0xf0 [ 8298.566632] [<78417007>] tcp_sendmsg+0x402/0x99b [ 8298.566632] [<781099cf>] ? sched_clock+0x1e/0x80 [ 8298.566632] [<7840dfef>] ? ip_finish_output+0x14c/0x310 [ 8298.566632] [<783cf1f8>] sock_aio_write+0x10f/0x129 [ 8298.566632] [<781099cf>] ? sched_clock+0x1e/0x80 [ 8298.566632] [<783cf0e9>] ? sock_aio_write+0x0/0x129 [ 8298.566632] [<781f46d8>] do_sync_readv_writev+0xdb/0x125 [ 8298.566632] [<7815b03d>] ? autoremove_wake_function+0x0/0x5b [ 8298.566632] [<781f44ee>] ? rw_copy_check_uvector+0x80/0x12f [ 8298.566632] [<781f5692>] do_readv_writev+0xb8/0x229 [ 8298.566632] [<783cf0e9>] ? sock_aio_write+0x0/0x129 [ 8298.566632] [<7814811a>] ? local_bh_enable_ip+0x75/0xfb [ 8298.566632] [<78170af9>] ? trace_hardirqs_on_caller+0x13a/0x188 [ 8298.566632] [<ffde4a78>] ? write_data+0xce/0xabf [iscsi_scst] [ 8298.566632] [<781f5862>] vfs_writev+0x5f/0x77 [ 8298.566632] [<ffde4b48>] write_data+0x19e/0xabf [iscsi_scst] [ 8298.566632] [<7816ee05>] ? put_lock_stats+0x18/0x45 [ 8298.566632] [<78170313>] ? lock_release_holdtime+0xaa/0x175 [ 8298.566632] [<ffddd309>] ? cmnd_set_sn+0x6f/0xa6 [iscsi_scst] [ 8298.566632] [<ffde5b3f>] iscsi_do_send+0x2a/0x63 [iscsi_scst] [ 8298.566632] [<ffde5f2e>] iscsi_send+0x1ca/0x359 [iscsi_scst] [ 8298.566632] [<7814811a>] ? local_bh_enable_ip+0x75/0xfb [ 8298.566632] [<ffddd542>] iscsi_try_local_processing+0x15c/0x1bd [iscsi_scst] [ 8298.566632] [<ffde133f>] iscsi_xmit_response+0x197/0x328 [iscsi_scst] [ 8298.566632] [<7816ee05>] ? put_lock_stats+0x18/0x45 [ 8298.566632] [<78170313>] ? lock_release_holdtime+0xaa/0x175 [ 8298.566632] [<f90ef48c>] scst_xmit_response+0x139/0x4ab [scst] [ 8298.566632] [<f90f12e5>] ? scst_pre_xmit_response+0xb0/0x274 [scst] [ 8298.566632] [<78170b60>] ? trace_hardirqs_on+0x19/0x2e [ 8298.566632] [<f90f356a>] scst_process_active_cmd+0x176/0x536 [scst] [ 8298.566632] [<f90ed88d>] ? scst_cmd_atomic+0x62/0xa3 [scst] [ 8298.566632] [<f90f3fc5>] scst_process_redirect_cmd+0x1b0/0x298 [scst] [ 8298.566632] [<f90f42b8>] scst_cmd_done_local+0xff/0x257 [scst] [ 8298.566632] [<f8e3447e>] vdisk_do_job+0x1f9/0xae2 [scst_vdisk] [ 8298.566632] [<78133a93>] ? finish_task_switch+0x69/0x105 [ 8298.566632] [<f90ed88d>] ? scst_cmd_atomic+0x62/0xa3 [scst] [ 8298.566632] [<f90f2a73>] scst_do_real_exec+0xbb/0x3fa [scst] [ 8298.566632] [<f90f2781>] ? scst_do_local_exec+0x143/0x23a [scst] [ 8298.566632] [<f90f2e82>] scst_exec+0xd0/0x25e [scst] [ 8298.566632] [<ffddd3a5>] ? scst_cmd_atomic+0x65/0xa6 [iscsi_scst] [ 8298.566632] [<f90f3150>] scst_send_for_exec+0x140/0x2a5 [scst] [ 8298.566632] [<f90ed67c>] ? scst_tgt_pre_exec+0x77/0x226 [scst] [ 8298.566632] [<f90f37a9>] scst_process_active_cmd+0x3b5/0x536 [scst] [ 8298.566632] [<7849e1ea>] ? sub_preempt_count+0x9a/0xd3 [ 8298.566632] [<f90f39ba>] scst_do_job_active+0x90/0x158 [scst] [ 8298.566632] [<f90f3c22>] scst_cmd_thread+0xc1/0x279 [scst] [ 8298.566632] [<7849b855>] ? _spin_unlock_irqrestore+0x8b/0x90 [ 8298.566632] [<7813b430>] ? default_wake_function+0x0/0x3d [ 8298.566632] [<f90f3b61>] ? scst_cmd_thread+0x0/0x279 [scst] [ 8298.566632] [<7815ac79>] kthread+0x84/0x8d [ 8298.566632] [<7815abf5>] ? kthread+0x0/0x8d [ 8298.566632] [<78103f57>] kernel_thread_helper+0x7/0x10Thanks,
Vlad