On Tue, 27 Nov 2012, Dave Jones wrote: > Hugh, > > We had a user report hitting the BUG_ON at the end of shmem_evict_inode. > I see in 3.7 you changed this to a WARN instead. > > Does the trace below match the one you described chasing in commit > 0f3c42f522dc1ad7e27affc0a4aa8c790bce0a66 ? The trace fits (apart from, I hit mine in the days before task_work_run was used for fput), but that doesn't tell us anything much. > > Full report at https://bugzilla.redhat.com/show_bug.cgi?id=879422, though > there's not much more than the trace tbh. It does say "system was idle", which makes me think that this has to have a different cause from my race between eviction and swapout. Of course, the change from BUG_ON to WARN_ON would equally neuter this crash, but it looks to me like a sign of... something else. Please do let me know if more keep coming. Hugh > > Dave > > > :kernel BUG at mm/shmem.c:657! > :invalid opcode: 0000 [#1] SMP > :CPU 1 > :Pid: 1017, comm: kwin Not tainted 3.6.6-1.fc17.x86_64 #1 System manufacturer P5E-VM HDMI/P5E-VM HDMI > :RIP: 0010:[<ffffffff81145792>] [<ffffffff81145792>] shmem_evict_inode+0x112/0x120 > :RSP: 0018:ffff88012b94ddb8 EFLAGS: 00010282 > :RAX: 0000000050aeab47 RBX: ffff880117a424a8 RCX: 0000000000000018 > :RDX: 000000001fea11fd RSI: 0000000005537c1c RDI: ffffffff81f1d500 > :RBP: ffff88012b94ddd8 R08: 0000000000000000 R09: 0000000000000000 > :R10: 0000000000000000 R11: 0000000000000000 R12: ffff880117a424a8 > :R13: ffff880117a424a8 R14: ffff880117a424b8 R15: ffff880139a79220 > :FS: 00007fa606014880(0000) GS:ffff88013fc80000(0000) knlGS:0000000000000000 > :CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > :CR2: 00007fa5f0021010 CR3: 000000012c2d0000 CR4: 00000000000007e0 > :DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > :DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 > :Process kwin (pid: 1017, threadinfo ffff88012b94c000, task ffff880134f30000) > :Stack: > : ffff880117a424b8 ffff880117a425b0 ffffffff81812f80 ffffffff81812f80 > : ffff88012b94de08 ffffffff811a8da2 ffff88012b94dde8 ffff880117a424b8 > : ffff880117a42540 ffff880139a34000 ffff88012b94de38 ffffffff811a8fa3 > :Call Trace: > : [<ffffffff811a8da2>] evict+0xa2/0x1a0 > : [<ffffffff811a8fa3>] iput+0x103/0x1f0 > : [<ffffffff811a50e8>] d_kill+0xd8/0x110 > : [<ffffffff811a5782>] dput+0xe2/0x1b0 > : [<ffffffff811900d6>] __fput+0x166/0x240 > : [<ffffffff811901be>] ____fput+0xe/0x10 > : [<ffffffff8107beab>] task_work_run+0x6b/0x90 > : [<ffffffff81013921>] do_notify_resume+0x71/0xb0 > : [<ffffffff81625be2>] int_signal+0x12/0x17 > :Code: c7 80 1c c4 81 e8 8f 5a 4d 00 48 89 df e8 77 80 1a 00 49 89 5e e0 49 89 5e e8 48 c7 c7 80 1c c4 81 e8 13 5a 4d 00 e9 1c ff ff ff <0f> 0b 66 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 41 > :RIP [<ffffffff81145792>] shmem_evict_inode+0x112/0x120 > : RSP <ffff88012b94ddb8> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>