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INFO: task hung in lookup_slow (2)

Status: auto-closed as invalid on 2019/11/26 02:54
Subsystems: fs
[Documentation on labels]
First crash: 1708d, last: 1696d
▶ ▼ Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in lookup_slow exfat 148 1917d 2210d 0/26 closed as dup on 2018/09/08 15:36
linux-6.1 INFO: task hung in lookup_slow 3 2d10h 5d06h 0/3 upstream: reported on 2024/04/14 05:59
linux-5.15 INFO: task hung in lookup_slow (2) 4 2d07h 4d08h 0/3 upstream: reported on 2024/04/15 04:02
upstream INFO: task hung in lookup_slow (3) exfat arm C unreliable 118 57m 525d 0/26 upstream: reported C repro on 2022/11/11 00:21
android-49 INFO: task hung in lookup_slow syz 36 1722d 1832d 0/3 public: reported syz repro on 2019/04/14 08:51
linux-4.14 INFO: task hung in lookup_slow C error 1 595d 625d 0/1 upstream: reported C repro on 2022/08/03 08:46
linux-4.19 INFO: task hung in lookup_slow 1 1404d 1404d 0/1 auto-closed as invalid on 2020/10/13 00:17
linux-5.15 INFO: task hung in lookup_slow 2 368d 373d 0/3 auto-obsoleted due to no activity on 2023/08/15 05:05

Sample crash report:
INFO: task syz-executor.1:9143 blocked for more than 143 seconds.
      Not tainted 5.3.0-rc6+ #128
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D29048  9143   9822 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xd9/0x260 kernel/sched/core.c:3947
 rwsem_down_read_slowpath+0x4cc/0xfb0 kernel/locking/rwsem.c:1090
 __down_read kernel/locking/rwsem.c:1320 [inline]
 down_read+0x1f4/0x3f0 kernel/locking/rwsem.c:1463
 inode_lock_shared include/linux/fs.h:788 [inline]
 lookup_slow+0x4a/0x80 fs/namei.c:1685
 walk_component+0x747/0x2000 fs/namei.c:1808
 lookup_last fs/namei.c:2271 [inline]
 path_lookupat.isra.0+0x1f5/0x8d0 fs/namei.c:2316
 filename_lookup+0x1b0/0x410 fs/namei.c:2346
 user_path_at_empty+0x43/0x50 fs/namei.c:2606
 user_path_at include/linux/namei.h:60 [inline]
 ksys_chdir+0x98/0x1f0 fs/open.c:459
 __do_sys_chdir fs/open.c:481 [inline]
 __se_sys_chdir fs/open.c:479 [inline]
 __x64_sys_chdir+0x31/0x40 fs/open.c:479
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459879
Code: 30 48 c7 44 24 38 00 00 00 00 48 c7 44 24 40 00 00 00 00 48 c7 44 24 48 00 00 00 00 e8 b0 67 ff ff 48 8b 44 24 50 48 8b 4c 24 <58> 48 89 01 48 8b 6c 24 60 48 83 c4 68 c3 e8 14 06 fd ff 0f 0b e8
RSP: 002b:00007f6f1f11fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000050
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000459879
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000000
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6f1f1206d4
R13: 00000000004bf0ea R14: 00000000004d1a20 R15: 00000000ffffffff
INFO: task syz-executor.1:9144 blocked for more than 143 seconds.
      Not tainted 5.3.0-rc6+ #128
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D28624  9144   9822 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xd9/0x260 kernel/sched/core.c:3947
 rwsem_down_read_slowpath+0x4cc/0xfb0 kernel/locking/rwsem.c:1090
 __down_read kernel/locking/rwsem.c:1320 [inline]
 down_read+0x1f4/0x3f0 kernel/locking/rwsem.c:1463
 inode_lock_shared include/linux/fs.h:788 [inline]
 lookup_slow+0x4a/0x80 fs/namei.c:1685
 walk_component+0x747/0x2000 fs/namei.c:1808
 lookup_last fs/namei.c:2271 [inline]
 path_lookupat.isra.0+0x1f5/0x8d0 fs/namei.c:2316
 filename_lookup+0x1b0/0x410 fs/namei.c:2346
 user_path_at_empty+0x43/0x50 fs/namei.c:2606
 user_path_at include/linux/namei.h:60 [inline]
 path_listxattr+0x98/0x160 fs/xattr.c:639
 __do_sys_listxattr fs/xattr.c:654 [inline]
 __se_sys_listxattr fs/xattr.c:651 [inline]
 __x64_sys_listxattr+0x78/0xb0 fs/xattr.c:651
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459879
Code: 30 48 c7 44 24 38 00 00 00 00 48 c7 44 24 40 00 00 00 00 48 c7 44 24 48 00 00 00 00 e8 b0 67 ff ff 48 8b 44 24 50 48 8b 4c 24 <58> 48 89 01 48 8b 6c 24 60 48 83 c4 68 c3 e8 14 06 fd ff 0f 0b e8
RSP: 002b:00007f6f1f0fec78 EFLAGS: 00000246 ORIG_RAX: 00000000000000c2
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459879
RDX: 00000000000000b1 RSI: 00000000200004c0 RDI: 0000000020000140
RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6f1f0ff6d4
R13: 00000000004c0149 R14: 00000000004da4c8 R15: 00000000ffffffff
INFO: task syz-executor.1:9145 blocked for more than 144 seconds.
      Not tainted 5.3.0-rc6+ #128
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D29936  9145   9822 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xd9/0x260 kernel/sched/core.c:3947
 rwsem_down_write_slowpath+0x708/0xf60 kernel/locking/rwsem.c:1214
 __down_write kernel/locking/rwsem.c:1365 [inline]
 down_write_nested+0x140/0x160 kernel/locking/rwsem.c:1597
 inode_lock_nested include/linux/fs.h:813 [inline]
 filename_create+0x17c/0x4f0 fs/namei.c:3634
 user_path_create fs/namei.c:3692 [inline]
 do_mkdirat+0xb5/0x2a0 fs/namei.c:3830
 __do_sys_mkdir fs/namei.c:3854 [inline]
 __se_sys_mkdir fs/namei.c:3852 [inline]
 __x64_sys_mkdir+0x5c/0x80 fs/namei.c:3852
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459879
Code: 30 48 c7 44 24 38 00 00 00 00 48 c7 44 24 40 00 00 00 00 48 c7 44 24 48 00 00 00 00 e8 b0 67 ff ff 48 8b 44 24 50 48 8b 4c 24 <58> 48 89 01 48 8b 6c 24 60 48 83 c4 68 c3 e8 14 06 fd ff 0f 0b e8
RSP: 002b:00007f6f1f0ddc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000459879
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000080
RBP: 000000000075c118 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6f1f0de6d4
R13: 00000000004bf081 R14: 00000000004da720 R15: 00000000ffffffff
INFO: task syz-executor.1:9146 blocked for more than 144 seconds.
      Not tainted 5.3.0-rc6+ #128
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D29600  9146   9822 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xd9/0x260 kernel/sched/core.c:3947
 rwsem_down_read_slowpath+0x4cc/0xfb0 kernel/locking/rwsem.c:1090
 __down_read kernel/locking/rwsem.c:1320 [inline]
 down_read+0x1f4/0x3f0 kernel/locking/rwsem.c:1463
 inode_lock_shared include/linux/fs.h:788 [inline]
 lookup_slow+0x4a/0x80 fs/namei.c:1685
 walk_component+0x747/0x2000 fs/namei.c:1808
 lookup_last fs/namei.c:2271 [inline]
 path_lookupat.isra.0+0x1f5/0x8d0 fs/namei.c:2316
 filename_lookup+0x1b0/0x410 fs/namei.c:2346
 user_path_at_empty+0x43/0x50 fs/namei.c:2606
 user_path include/linux/namei.h:65 [inline]
 do_mount+0x150/0x1c30 fs/namespace.c:3049
 ksys_mount+0xdb/0x150 fs/namespace.c:3320
 __do_sys_mount fs/namespace.c:3334 [inline]
 __se_sys_mount fs/namespace.c:3331 [inline]
 __x64_sys_mount+0xbe/0x150 fs/namespace.c:3331
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459879
Code: Bad RIP value.
RSP: 002b:00007f6f1f0bcc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459879
RDX: 0000000020000300 RSI: 0000000020000200 RDI: 0000000000000000
RBP: 000000000075c1c0 R08: 00000000200005c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6f1f0bd6d4
R13: 00000000004c5e2f R14: 00000000004da930 R15: 00000000ffffffff
INFO: task syz-executor.1:9147 blocked for more than 144 seconds.
      Not tainted 5.3.0-rc6+ #128
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D29936  9147   9822 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xd9/0x260 kernel/sched/core.c:3947
 rwsem_down_write_slowpath+0x708/0xf60 kernel/locking/rwsem.c:1214
 __down_write kernel/locking/rwsem.c:1365 [inline]
 down_write_nested+0x140/0x160 kernel/locking/rwsem.c:1597
 inode_lock_nested include/linux/fs.h:813 [inline]
 filename_create+0x17c/0x4f0 fs/namei.c:3634
 user_path_create fs/namei.c:3692 [inline]
 do_mknodat fs/namei.c:3753 [inline]
 do_mknodat+0x1a4/0x480 fs/namei.c:3741
 __do_sys_mknod fs/namei.c:3793 [inline]
 __se_sys_mknod fs/namei.c:3791 [inline]
 __x64_sys_mknod+0x7b/0xb0 fs/namei.c:3791
 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459879
Code: Bad RIP value.
RSP: 002b:00007f6f1f09bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000085
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459879
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000180
RBP: 000000000075c268 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6f1f09c6d4
R13: 00000000004c5d4c R14: 00000000004da780 R15: 00000000ffffffff
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 PID: 1057 Comm: khungtaskd Not tainted 5.3.0-rc6+ #128
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
 watchdog+0x9d0/0xef0 kernel/hung_task.c:289
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0-rc6+ #128
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__kasan_check_write+0x0/0x20 mm/kasan/common.c:97
Code: 1a bc af ff e9 da ee ff ff 90 55 89 f6 31 d2 48 89 e5 48 8b 4d 08 e8 cf 26 00 00 5d c3 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 <55> 89 f6 ba 01 00 00 00 48 89 e5 48 8b 4d 08 e8 ac 26 00 00 5d c3
RSP: 0018:ffff8880ae809e90 EFLAGS: 00000202
RAX: ffff8880ae800000 RBX: ffff8880ae835680 RCX: 0000000000000000
RDX: 1ffffffff1139028 RSI: 0000000000000004 RDI: ffff8880ae8356e0
RBP: ffff8880ae809ed8 R08: ffffffff889c8140 R09: ffffed1015d06add
R10: ffffed1015d06adc R11: ffff8880ae8356e3 R12: ffff8880ae835680
R13: ffff8880ae836148 R14: 0000000000000001 R15: ffff8880ae8356e0
FS:  0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c42c762c00 CR3: 00000000a3eb7000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __do_softirq+0x262/0x98c kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x19b/0x1e0 kernel/softirq.c:413
 scheduler_ipi+0x3ae/0x640 kernel/sched/core.c:2228
 smp_reschedule_interrupt+0x78/0x4c0 arch/x86/kernel/smp.c:276
 reschedule_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:854
 </IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: 48 c2 6e fa eb 8a 90 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 04 6d 4a 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d f4 6c 4a 00 fb f4 <c3> 90 55 48 89 e5 41 57 41 56 41 55 41 54 53 e8 6e 83 22 fa e8 29
RSP: 0018:ffffffff88c07ce8 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff02
RAX: 1ffffffff11a5e8d RBX: ffffffff88c7a1c0 RCX: 1ffffffff134b5de
RDX: dffffc0000000000 RSI: ffffffff8177f03e RDI: ffffffff873db36c
RBP: ffffffff88c07d18 R08: ffffffff88c7a1c0 R09: fffffbfff118f439
R10: fffffbfff118f438 R11: ffffffff88c7a1c7 R12: dffffc0000000000
R13: ffffffff89a57cf8 R14: 0000000000000000 R15: 0000000000000000
 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:571
 default_idle_call+0x84/0xb0 kernel/sched/idle.c:94
 cpuidle_idle_call kernel/sched/idle.c:154 [inline]
 do_idle+0x413/0x760 kernel/sched/idle.c:263
 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:354
 rest_init+0x245/0x37b init/main.c:451
 arch_call_rest_init+0xe/0x1b
 start_kernel+0x912/0x951 init/main.c:785
 x86_64_start_reservations+0x29/0x2b arch/x86/kernel/head64.c:472
 x86_64_start_kernel+0x77/0x7b arch/x86/kernel/head64.c:453
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/08/28 02:50 upstream 6525771f58cb fd37b39e .config console log report ci-upstream-kasan-gce-root
2019/08/15 18:29 upstream 41de59634046 0d298d6b .config console log report ci-upstream-kasan-gce-selinux-root
* Struck through repros no longer work on HEAD.