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BUG: soft lockup in umount_tree

Status: auto-closed as invalid on 2019/02/22 13:39
First crash: 2117d, last: 2101d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-49 BUG: soft lockup in umount_tree C 1 2108d 1831d 0/3 public: reported C repro on 2019/04/14 08:51

Sample crash report:
NMI watchdog: BUG: soft lockup - CPU#1 stuck for 134s! [syz-executor6:10780]
Modules linked in:
irq event stamp: 916070
hardirqs last  enabled at (916069): [<ffffffff838c2469>] restore_regs_and_iret+0x0/0x1d
hardirqs last disabled at (916070): [<ffffffff838c33cb>] apic_timer_interrupt+0x9b/0xb0 arch/x86/entry/entry_64.S:741
softirqs last  enabled at (916068): [<ffffffff838c4fdf>] __do_softirq+0x4df/0xa1a kernel/softirq.c:299
softirqs last disabled at (916063): [<ffffffff8113f8ad>] invoke_softirq kernel/softirq.c:350 [inline]
softirqs last disabled at (916063): [<ffffffff8113f8ad>] irq_exit+0x10d/0x140 kernel/softirq.c:391
CPU: 1 PID: 10780 Comm: syz-executor6 Not tainted 4.4.139-g7ba5557 #65
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801cc3a6000 task.stack: ffff8801bb220000
RIP: 0010:[<ffffffff815b29d2>]  [<ffffffff815b29d2>] do_make_slave fs/pnode.c:83 [inline]
RIP: 0010:[<ffffffff815b29d2>]  [<ffffffff815b29d2>] change_mnt_propagation+0xe2/0xb70 fs/pnode.c:130
RSP: 0018:ffff8801bb227b08  EFLAGS: 00000246
RAX: 1ffff10015b1e356 RBX: ffff8800b5aaca00 RCX: ffffc900032a3000
RDX: 0000000000040000 RSI: ffffffff815b29b0 RDI: ffff8800ad8f1ab0
RBP: ffff8801bb227b60 R08: ffff8800b5aaca68 R09: 0000000000000001
R10: 0000000000000000 R11: ffff8801cc3a6000 R12: ffff8800ad8f1a00
R13: 0000000000040000 R14: dffffc0000000000 R15: ffff8800ad8f1cb0
FS:  00007f620501e700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5dc05b2140 CR3: 00000001d3023000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff8157e63d ffff8800b5aaca00 0000000000000000 ffff8800b5aaca20
 ffff8800b5aacae0 ffffed0016b55944 ffff8800b5aaca90 dffffc0000000000
 ffff8800b5aaca00 ffff8801d2dc9a20 ffff8801bb227c00 ffff8801bb227c28
Call Trace:
 [<ffffffff8157ed56>] umount_tree+0x326/0x810 fs/namespace.c:1501
 [<ffffffff8158714c>] attach_recursive_mnt+0x74c/0x8e0 fs/namespace.c:2035
 [<ffffffff8158744f>] graft_tree+0x16f/0x1f0 fs/namespace.c:2099
 [<ffffffff81589ce8>] do_loopback fs/namespace.c:2220 [inline]
 [<ffffffff81589ce8>] do_mount+0x20e8/0x2860 fs/namespace.c:2827
 [<ffffffff8158ae70>] SYSC_mount fs/namespace.c:3027 [inline]
 [<ffffffff8158ae70>] SyS_mount+0x130/0x1d0 fs/namespace.c:3005
 [<ffffffff838c1865>] entry_SYSCALL_64_fastpath+0x22/0x9e
Code: 13 02 00 00 e8 00 eb d9 ff 49 8d bc 24 b0 00 00 00 48 89 f8 48 c1 e8 03 42 80 3c 30 00 0f 85 41 08 00 00 4d 8b bc 24 b0 00 00 00 <49> 8d 97 50 ff ff ff 48 39 d3 49 89 d4 75 90 48 89 55 d0 e8 c6 
Sending NMI to other CPUs:
NMI backtrace for cpu 0
CPU: 0 PID: 1 Comm: init Not tainted 4.4.139-g7ba5557 #65
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d99a8000 task.stack: ffff8801d99b0000
RIP: 0010:[<ffffffff81547701>]  [<ffffffff81547701>] rep_nop arch/x86/include/asm/processor.h:562 [inline]
RIP: 0010:[<ffffffff81547701>]  [<ffffffff81547701>] cpu_relax arch/x86/include/asm/processor.h:567 [inline]
RIP: 0010:[<ffffffff81547701>]  [<ffffffff81547701>] __read_seqcount_begin include/linux/seqlock.h:114 [inline]
RIP: 0010:[<ffffffff81547701>]  [<ffffffff81547701>] raw_read_seqcount_begin include/linux/seqlock.h:147 [inline]
RIP: 0010:[<ffffffff81547701>]  [<ffffffff81547701>] read_seqcount_begin include/linux/seqlock.h:164 [inline]
RIP: 0010:[<ffffffff81547701>]  [<ffffffff81547701>] read_seqbegin include/linux/seqlock.h:430 [inline]
RIP: 0010:[<ffffffff81547701>]  [<ffffffff81547701>] path_init+0x1331/0x1910 fs/namei.c:2052
RSP: 0018:ffff8801d99b7af8  EFLAGS: 00000293
RAX: ffff8801d99a8000 RBX: ffff8801d99b7c30 RCX: ffffffff844095c0
RDX: 0000000000000000 RSI: ffffffff815476ff RDI: 0000000000000246
RBP: ffff8801d99b7b98 R08: ffffffff85348370 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: fffffbfff08812b8
R13: ffffffff844095c0 R14: 0000000000000041 R15: ffff8800b19ed51c
FS:  00007f1eeb0877a0(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4c91903c60 CR3: 00000000b660a000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff8154b92a 0000000000000001 ffff8801d99b7b88 0000000000000046
 0000000000000000 ffffffff81e6eb8e ffff8801d99a88d8 0000000200000000
 ffff8801d99a88e0 0000000000000046 ffffffff841e96b8 ffff8801d99b7c68
Call Trace:
 [<ffffffff8154b92a>] path_lookupat.isra.36+0x2a/0x410 fs/namei.c:2148
 [<ffffffff81550657>] filename_lookup.part.53+0x177/0x370 fs/namei.c:2188
 [<ffffffff81550a13>] filename_lookup fs/namei.c:2181 [inline]
 [<ffffffff81550a13>] user_path_at_empty+0x53/0x70 fs/namei.c:2362
 [<ffffffff8152b2b6>] user_path_at include/linux/namei.h:52 [inline]
 [<ffffffff8152b2b6>] vfs_fstatat+0xc6/0x170 fs/stat.c:106
 [<ffffffff8152c456>] vfs_stat fs/stat.c:123 [inline]
 [<ffffffff8152c456>] SYSC_newstat+0x86/0xf0 fs/stat.c:270
 [<ffffffff8152c85d>] SyS_newstat+0x1d/0x30 fs/stat.c:266
 [<ffffffff838c1865>] entry_SYSCALL_64_fastpath+0x22/0x9e
Code: ed ff ff e8 b2 21 fb ff e9 ba ed ff ff 48 b8 00 00 00 00 00 fc ff df 49 89 cc 49 89 cd 49 c1 ec 03 49 01 c4 e8 b1 9d e0 ff f3 90 <41> 0f b6 04 24 84 c0 74 08 3c 03 0f 8e 50 04 00 00 41 8b 45 00 

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/07/03 19:22 https://android.googlesource.com/kernel/common android-4.4 7ba55570970c 317fc8ea .config console log report ci-android-44-kasan-gce
2018/07/01 23:41 https://android.googlesource.com/kernel/common android-4.4 cf21a9ac5ee4 dba0b50e .config console log report ci-android-44-kasan-gce
2018/07/18 00:21 https://android.googlesource.com/kernel/common android-4.4 b1bad9e2324d 6d5bd5b5 .config console log report ci-android-44-kasan-gce-386
* Struck through repros no longer work on HEAD.