On 2009-01-30 11:23, Andrea Righi wrote: > On 2009-01-30 05:15, Andrey Borzenkov wrote: >> On 29 of January 2009 12:10:11 Geert Uytterhoeven wrote: >>> On Tue, 27 Jan 2009, Andrey Borzenkov wrote: >>>> I do not know if this is new; I usually do not hibernate at all and >>>> was testing another driver actually. I do not remember such issues >>>> in 2.6.28 though. Dmesg follows; config attached. >>>> >>>> [11715.652498] >>>> ======================================================= >>>> [11715.652520] [ INFO: possible circular locking dependency >>>> detected ] [11715.652534] 2.6.29-rc2-1avb #11 >>>> [11715.652541] >>>> ------------------------------------------------------- >>>> [11715.652550] s2disk/25519 is trying to acquire lock: >>>> [11715.652562] (&fb_info->lock){--..}, at: [<c0223017>] >>>> fb_mmap+0x97/0x170 [11715.652623] >>>> [11715.652625] but task is already holding lock: >>>> [11715.652632] (&mm->mmap_sem){----}, at: [<c010639e>] >>>> sys_mmap2+0x8e/0xc0 [11715.652669] >>>> [11715.652671] which lock already depends on the new lock. >>>> [11715.652675] >>>> [11715.652681] >>>> [11715.652683] the existing dependency chain (in reverse order) is: >>>> [11715.652691] >>>> [11715.652693] -> #1 (&mm->mmap_sem){----}: >>>> [11715.652707] [<c0144ecf>] __lock_acquire+0x129f/0x1930 >>>> [11715.652730] [<c01455bc>] lock_acquire+0x5c/0x80 >>>> [11715.652742] [<c0181e57>] might_fault+0x77/0xa0 >>>> [11715.652764] [<c0209325>] copy_from_user+0x35/0x130 >>>> [11715.652782] [<c0223ef5>] fb_ioctl+0x1d5/0x3f0 >>>> [11715.652797] [<c01a51d0>] vfs_ioctl+0x20/0x80 >>>> [11715.652832] [<c01a53e2>] do_vfs_ioctl+0x72/0x570 >>>> [11715.652845] [<c01a5919>] sys_ioctl+0x39/0x70 >>>> [11715.652857] [<c0103371>] sysenter_do_call+0x12/0x31 >>>> [11715.652870] [<ffffffff>] 0xffffffff >>>> [11715.652973] >>>> [11715.652975] -> #0 (&fb_info->lock){--..}: >>>> [11715.652988] [<c014503c>] __lock_acquire+0x140c/0x1930 >>>> [11715.653000] [<c01455bc>] lock_acquire+0x5c/0x80 >>>> [11715.653011] [<c030761a>] mutex_lock_nested+0xba/0x2f0 >>>> [11715.653032] [<c0223017>] fb_mmap+0x97/0x170 >>>> [11715.653044] [<c0188996>] mmap_region+0x1d6/0x530 >>>> [11715.653067] [<c0188ec3>] do_mmap_pgoff+0x1d3/0x2f0 >>>> [11715.653079] [<c01063bd>] sys_mmap2+0xad/0xc0 >>>> [11715.653091] [<c0103371>] sysenter_do_call+0x12/0x31 >>>> [11715.653102] [<ffffffff>] 0xffffffff >>>> [11715.653116] >>>> [11715.653119] other info that might help us debug this: >>>> [11715.653122] >>>> [11715.653130] 1 lock held by s2disk/25519: >>>> [11715.653137] #0: (&mm->mmap_sem){----}, at: [<c010639e>] >>>> sys_mmap2+0x8e/0xc0 >>>> [11715.653156] >>>> [11715.653158] stack backtrace: >>>> [11715.653170] Pid: 25519, comm: s2disk Not tainted 2.6.29-rc2-1avb >>>> #11 [11715.653179] Call Trace: >>>> [11715.653190] [<c0306248>] ? printk+0x18/0x20 >>>> [11715.653202] [<c01437df>] print_circular_bug_tail+0xcf/0xe0 >>>> [11715.653213] [<c014503c>] __lock_acquire+0x140c/0x1930 >>>> [11715.653224] [<c014328b>] ? trace_hardirqs_on+0xb/0x10 >>>> [11715.653242] [<c0309125>] ? _spin_unlock_irqrestore+0x35/0x60 >>>> [11715.653254] [<c0140dc5>] ? lock_release_holdtime+0x35/0x210 >>>> [11715.653265] [<c01455bc>] lock_acquire+0x5c/0x80 >>>> [11715.653277] [<c0223017>] ? fb_mmap+0x97/0x170 >>>> [11715.653287] [<c030761a>] mutex_lock_nested+0xba/0x2f0 >>>> [11715.653298] [<c0223017>] ? fb_mmap+0x97/0x170 >>>> [11715.653309] [<c0223017>] ? fb_mmap+0x97/0x170 >>>> [11715.653335] [<c019514d>] ? kmem_cache_alloc+0xad/0x100 >>>> [11715.653347] [<c0223017>] fb_mmap+0x97/0x170 >>>> [11715.653358] [<c0188996>] mmap_region+0x1d6/0x530 >>>> [11715.653371] [<c0186a9d>] ? >>>> arch_get_unmapped_area_topdown+0x10d/0x170 [11715.653383] >>>> [<c0188ec3>] do_mmap_pgoff+0x1d3/0x2f0 >>>> [11715.653395] [<c01063bd>] sys_mmap2+0xad/0xc0 >>>> [11715.653406] [<c0103371>] sysenter_do_call+0x12/0x31 >>> Is this fixed by http://patchwork.kernel.org/patch/3259/? >>> >> No. It just makes stack a bit more deep :) > > yep! :) > > Probably we should simply use an atomic notifier there, instead of blocking. > I'll do some tests and post a new fix. No, the solution is no so trivial. Some notifier callbacks can sleep, so the usage of a blocking notifier is mandatory. It seems we need a more complicated solution to totally fix it. At least the previous fix avoids the circular locking of fb_info->lock and mm->mmap_sem due to copy_from/to_user() called with fb_info->lock held... -Andrea > > Thanks, > -Andrea > >> [ 408.267429] ======================================================= >> [ 408.267448] [ INFO: possible circular locking dependency detected ] >> [ 408.267462] 2.6.29-rc3-1avb #14 >> [ 408.267469] ------------------------------------------------------- >> [ 408.267478] s2disk/5695 is trying to acquire lock: >> [ 408.267487] (&fb_info->lock){--..}, at: [<c02235e7>] >> fb_mmap+0x97/0x170 >> [ 408.267544] >> [ 408.267546] but task is already holding lock: >> [ 408.267553] (&mm->mmap_sem){----}, at: [<c010639e>] >> sys_mmap2+0x8e/0xc0 >> [ 408.267591] >> [ 408.267593] which lock already depends on the new lock. >> [ 408.267596] >> [ 408.267603] >> [ 408.267604] the existing dependency chain (in reverse order) is: >> [ 408.267612] >> [ 408.267614] -> #3 (&mm->mmap_sem){----}: >> [ 408.267628] [<c014520f>] __lock_acquire+0x129f/0x1930 >> [ 408.267650] [<c01458fc>] lock_acquire+0x5c/0x80 >> [ 408.267661] [<c0182117>] might_fault+0x77/0xa0 >> [ 408.267683] [<c0209916>] copy_to_user+0x36/0x120 >> [ 408.267699] [<c01a60f7>] filldir+0x97/0xe0 >> [ 408.267735] [<c01de339>] sysfs_readdir+0x129/0x220 >> [ 408.267751] [<c01a62a6>] vfs_readdir+0x86/0xa0 >> [ 408.267763] [<c01a63e8>] sys_getdents+0x68/0xc0 >> [ 408.267775] [<c010344a>] syscall_call+0x7/0xb >> [ 408.267787] [<ffffffff>] 0xffffffff >> [ 408.267862] >> [ 408.267864] -> #2 (sysfs_mutex){--..}: >> [ 408.267877] [<c014520f>] __lock_acquire+0x129f/0x1930 >> [ 408.267889] [<c01458fc>] lock_acquire+0x5c/0x80 >> [ 408.267899] [<c0307f3a>] mutex_lock_nested+0xba/0x2f0 >> [ 408.267921] [<c01de6cc>] sysfs_addrm_start+0x2c/0xc0 >> [ 408.267933] [<c01dec80>] create_dir+0x40/0x90 >> [ 408.267944] [<c01decfb>] sysfs_create_dir+0x2b/0x50 >> [ 408.267955] [<c02036bc>] kobject_add_internal+0xbc/0x1b0 >> [ 408.267984] [<c0203881>] kobject_add_varg+0x31/0x50 >> [ 408.267996] [<c02038fc>] kobject_add+0x2c/0x60 >> [ 408.268008] [<c0273448>] device_add+0xa8/0x550 >> [ 408.268041] [<c0273902>] device_register+0x12/0x20 >> [ 408.268053] [<c02739bb>] device_create_vargs+0xab/0xc0 >> [ 408.268065] [<c02739f8>] device_create+0x28/0x30 >> [ 408.268077] [<c026cc6d>] register_con_driver+0xed/0x130 >> [ 408.268090] [<c026e18b>] take_over_console+0x1b/0x50 >> [ 408.268102] [<c023052d>] fbcon_takeover+0x5d/0xb0 >> [ 408.268125] [<c02311a0>] fbcon_event_notify+0x820/0x900 >> [ 408.268137] [<c030c3b3>] notifier_call_chain+0x53/0xa0 >> [ 408.268161] [<c0138ab4>] >> __blocking_notifier_call_chain+0x44/0x60 >> [ 408.268184] [<c0138aea>] >> blocking_notifier_call_chain+0x1a/0x20 >> [ 408.268197] [<c0222f81>] fb_notifier_call_chain+0x11/0x20 >> [ 408.268209] [<c0223f08>] register_framebuffer+0x168/0x220 >> [ 408.268223] [<c0414ba2>] vesafb_probe+0x542/0x783 >> [ 408.268250] [<c02765af>] platform_drv_probe+0xf/0x20 >> [ 408.268269] [<c02757c7>] driver_probe_device+0x87/0x1b0 >> [ 408.268281] [<c0275988>] __device_attach+0x8/0x10 >> [ 408.268291] [<c0274e0b>] bus_for_each_drv+0x5b/0x80 >> [ 408.268308] [<c0275a36>] device_attach+0x76/0x80 >> [ 408.268319] [<c0274c27>] bus_attach_device+0x47/0x70 >> [ 408.268331] [<c02736c3>] device_add+0x323/0x550 >> [ 408.268342] [<c0276f85>] platform_device_add+0x175/0x1c0 >> [ 408.268358] [<c0414e7d>] vesafb_init+0x9a/0x1ec >> [ 408.268370] [<c010111a>] do_one_initcall+0x2a/0x160 >> [ 408.268382] [<c04004d5>] kernel_init+0x83/0xd5 >> [ 408.268411] [<c0103a77>] kernel_thread_helper+0x7/0x10 >> [ 408.268423] [<ffffffff>] 0xffffffff >> [ 408.268436] >> [ 408.268438] -> #1 ((fb_notifier_list).rwsem){----}: >> [ 408.268451] [<c014520f>] __lock_acquire+0x129f/0x1930 >> [ 408.268463] [<c01458fc>] lock_acquire+0x5c/0x80 >> [ 408.268474] [<c0308879>] down_read+0x49/0x90 >> [ 408.268484] [<c0138a9a>] >> __blocking_notifier_call_chain+0x2a/0x60 >> [ 408.268497] [<c0138aea>] >> blocking_notifier_call_chain+0x1a/0x20 >> [ 408.268509] [<c0222f81>] fb_notifier_call_chain+0x11/0x20 >> [ 408.268521] [<c022459e>] do_fb_ioctl+0x2ae/0x5d0 >> [ 408.268533] [<c02248dd>] fb_ioctl+0x1d/0x20 >> [ 408.268545] [<c01a54b0>] vfs_ioctl+0x20/0x80 >> [ 408.268558] [<c01a56c2>] do_vfs_ioctl+0x72/0x570 >> [ 408.268570] [<c01a5bf9>] sys_ioctl+0x39/0x70 >> [ 408.268581] [<c0103371>] sysenter_do_call+0x12/0x31 >> [ 408.268592] [<ffffffff>] 0xffffffff >> [ 408.268623] >> [ 408.268625] -> #0 (&fb_info->lock){--..}: >> [ 408.268638] [<c014537c>] __lock_acquire+0x140c/0x1930 >> [ 408.268649] [<c01458fc>] lock_acquire+0x5c/0x80 >> [ 408.268661] [<c0307f3a>] mutex_lock_nested+0xba/0x2f0 >> [ 408.268672] [<c02235e7>] fb_mmap+0x97/0x170 >> [ 408.268684] [<c0188c76>] mmap_region+0x1d6/0x530 >> [ 408.268706] [<c01891a3>] do_mmap_pgoff+0x1d3/0x2f0 >> [ 408.268718] [<c01063bd>] sys_mmap2+0xad/0xc0 >> [ 408.268729] [<c0103371>] sysenter_do_call+0x12/0x31 >> [ 408.268740] [<ffffffff>] 0xffffffff >> [ 408.268752] >> [ 408.268754] other info that might help us debug this: >> [ 408.268758] >> [ 408.268767] 1 lock held by s2disk/5695: >> [ 408.268773] #0: (&mm->mmap_sem){----}, at: [<c010639e>] >> sys_mmap2+0x8e/0xc0 >> [ 408.268792] >> [ 408.268794] stack backtrace: >> [ 408.268805] Pid: 5695, comm: s2disk Not tainted 2.6.29-rc3-1avb #14 >> [ 408.268814] Call Trace: >> [ 408.268825] [<c0306b68>] ? printk+0x18/0x20 >> [ 408.268836] [<c0143b1f>] print_circular_bug_tail+0xcf/0xe0 >> [ 408.268847] [<c014537c>] __lock_acquire+0x140c/0x1930 >> [ 408.268862] [<c01487f0>] ? futex_wait+0x170/0x450 >> [ 408.268881] [<c011826c>] ? try_to_wake_up+0x10c/0x120 >> [ 408.268894] [<c0309a45>] ? _spin_unlock_irqrestore+0x35/0x60 >> [ 408.268906] [<c0141105>] ? lock_release_holdtime+0x35/0x210 >> [ 408.268917] [<c01458fc>] lock_acquire+0x5c/0x80 >> [ 408.268928] [<c02235e7>] ? fb_mmap+0x97/0x170 >> [ 408.268939] [<c0307f3a>] mutex_lock_nested+0xba/0x2f0 >> [ 408.268950] [<c02235e7>] ? fb_mmap+0x97/0x170 >> [ 408.268961] [<c02235e7>] ? fb_mmap+0x97/0x170 >> [ 408.268987] [<c019542d>] ? kmem_cache_alloc+0xad/0x100 >> [ 408.268999] [<c02235e7>] fb_mmap+0x97/0x170 >> [ 408.269010] [<c0188c76>] mmap_region+0x1d6/0x530 >> [ 408.269023] [<c0186d7d>] ? >> arch_get_unmapped_area_topdown+0x10d/0x170 >> [ 408.269035] [<c01891a3>] do_mmap_pgoff+0x1d3/0x2f0 >> [ 408.269047] [<c01063bd>] sys_mmap2+0xad/0xc0 >> [ 408.269058] [<c0103371>] sysenter_do_call+0x12/0x31 -- Andrea Righi Jabber ID: righiandr@xxxxxxxxxxxxxxx gpg --keyserver pgp.mit.edu --recv-keys 77CEF397 _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm