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INFO: task hung in __do_page_fault

Status: upstream: reported C repro on 2019/04/19 08:53
Reported-by: syzbot+2b85df964d939e9d4d98@syzkaller.appspotmail.com
First crash: 2046d, last: 708d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-44 INFO: task hung in __do_page_fault C 1 2109d 2051d 0/2 public: reported C repro on 2019/04/14 00:00
upstream INFO: task hung in __do_page_fault (2) C done error 34 1936d 2220d 0/28 closed as invalid on 2022/02/08 10:55
android-49 INFO: task hung in __do_page_fault C 5 1877d 2051d 0/3 public: reported C repro on 2019/04/14 08:51
linux-4.19 INFO: task hung in __do_page_fault gfs2 C error 31 690d 1996d 0/1 upstream: reported C repro on 2019/06/08 06:01
android-414 INFO: task hung in __do_page_fault C 7 1886d 2053d 0/1 public: reported C repro on 2019/04/12 00:01
upstream INFO: task hung in __do_page_fault fs 1 2414d 2414d 5/28 fixed on 2018/05/17 10:02
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2022/11/10 18:30 9m retest repro linux-4.14.y report log
2022/11/10 17:30 11m retest repro linux-4.14.y report log
2022/11/10 15:30 10m retest repro linux-4.14.y report log
2022/11/10 14:30 9m retest repro linux-4.14.y report log
2022/11/10 13:30 9m retest repro linux-4.14.y report log
2022/11/10 12:30 9m retest repro linux-4.14.y report log
2022/11/10 11:30 9m retest repro linux-4.14.y report log
2022/11/10 10:30 9m retest repro linux-4.14.y report log
2022/11/10 09:30 10m retest repro linux-4.14.y report log
2022/11/10 08:30 11m retest repro linux-4.14.y report log
▶ ▼ Fix bisection attempts (7)
Created Duration User Patch Repo Result
2020/07/08 10:51 0m bisect fix linux-4.14.y error job log
2020/05/20 11:52 31m bisect fix linux-4.14.y OK (0) job log log
2020/04/20 11:18 33m bisect fix linux-4.14.y OK (0) job log log
2020/03/21 10:46 32m bisect fix linux-4.14.y OK (0) job log log
2020/02/20 10:14 31m bisect fix linux-4.14.y OK (0) job log log
2019/12/28 23:33 35m bisect fix linux-4.14.y OK (0) job log log
2019/11/28 23:01 31m bisect fix linux-4.14.y OK (0) job log log

Sample crash report:
INFO: task syz-executor122:26218 blocked for more than 140 seconds.
      Not tainted 4.14.284-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor122 D28912 26218   7982 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1e6/0x350 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x14/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 down_read+0x44/0x80 kernel/locking/rwsem.c:26
 __do_page_fault+0x7b8/0xad0 arch/x86/mm/fault.c:1378
 page_fault+0x45/0x50 arch/x86/entry/entry_64.S:1123
RIP: 79c2e4f0:0x7ffd79c2e510
RSP: 0064:0000000000000032 EFLAGS: 7f547e84a4bc
INFO: task syz-executor122:26237 blocked for more than 140 seconds.
      Not tainted 4.14.284-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor122 D28976 26237   7982 0x80000004
Call Trace:
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1e6/0x350 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x14/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 down_read+0x44/0x80 kernel/locking/rwsem.c:26
 exit_mm kernel/exit.c:511 [inline]
 do_exit+0x598/0x2850 kernel/exit.c:855
 do_group_exit+0x100/0x2e0 kernel/exit.c:965
 get_signal+0x38d/0x1ca0 kernel/signal.c:2412
 do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:792
 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f547e7c76d9
RSP: 002b:00007f547df48218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f547e84a4b8 RCX: 00007f547e7c76d9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f547e84a4b8
RBP: 00007f547e84a4b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f547e84a4bc
R13: 00007ffd79c2e43f R14: 00007f547df48300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1533:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff87028029>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
1 lock held by syz-executor122/26218:
 #0:  (&mm->mmap_sem){++++}, at: [<ffffffff812418a8>] __do_page_fault+0x7b8/0xad0 arch/x86/mm/fault.c:1378
1 lock held by syz-executor122/26237:
 #0:  (&mm->mmap_sem){++++}, at: [<ffffffff8131cb58>] exit_mm kernel/exit.c:511 [inline]
 #0:  (&mm->mmap_sem){++++}, at: [<ffffffff8131cb58>] do_exit+0x598/0x2850 kernel/exit.c:855

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 1533 Comm: khungtaskd Not tainted 4.14.284-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5b9/0xb40 kernel/hung_task.c:274
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 23630 Comm: syz-executor122 Not tainted 4.14.284-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88809746c040 task.stack: ffff8880a32d0000
RIP: 0010:perf_log_itrace_start+0xa0/0x4a0 kernel/events/core.c:7450
RSP: 0018:ffff8880a32d7300 EFLAGS: 00000046
RAX: 1ffff11013705c8f RBX: 0000000000000000 RCX: ffffffff88fcd220
RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff88809b82e478
RBP: ffff8880a32d75a8 R08: 1ffffffff11993ac R09: ffff88823fff700f
R10: ffff88823fff7017 R11: 000001702acbaaf0 R12: 1ffff1101465ae60
R13: ffff88809b82e1c0 R14: ffff88809b82e248 R15: 00000000000778e6
FS:  00007f547df69700(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000100 CR3: 000000009c55f000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 event_sched_in+0x447/0xdb0 kernel/events/core.c:2132
 group_sched_in+0xfb/0x400 kernel/events/core.c:2174
 ctx_flexible_sched_in kernel/events/core.c:3199 [inline]
 ctx_sched_in+0x1303/0x1860 kernel/events/core.c:3245
 perf_event_sched_in+0x69/0xa0 kernel/events/core.c:2332
 perf_event_context_sched_in kernel/events/core.c:3285 [inline]
 __perf_event_task_sched_in+0x5a3/0x8c0 kernel/events/core.c:3324
 perf_event_task_sched_in include/linux/perf_event.h:1087 [inline]
 finish_task_switch+0x3c9/0x610 kernel/sched/core.c:2667
 context_switch kernel/sched/core.c:2814 [inline]
 __schedule+0x893/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 _synchronize_rcu_expedited+0x522/0x770 kernel/rcu/tree_exp.h:615
 synchronize_rcu+0x98/0x130 kernel/rcu/tree_plugin.h:762
 ring_buffer_attach+0x34a/0x5e0 kernel/events/core.c:5112
 perf_mmap+0xd25/0x1390 kernel/events/core.c:5495
 call_mmap include/linux/fs.h:1785 [inline]
 mmap_region+0xa1a/0x1220 mm/mmap.c:1717
 do_mmap+0x5b3/0xcb0 mm/mmap.c:1495
 do_mmap_pgoff include/linux/mm.h:2185 [inline]
 vm_mmap_pgoff+0x14e/0x1a0 mm/util.c:333
 SYSC_mmap_pgoff mm/mmap.c:1545 [inline]
 SyS_mmap_pgoff+0x249/0x510 mm/mmap.c:1503
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f547e7c76d9
RSP: 002b:00007f547df691f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 000000000000001f RCX: 00007f547e7c76d9
RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffd000
RBP: 00007f547e84a4a0 R08: 0000000000000003 R09: 0000000000000000
R10: 0000000000000011 R11: 0000000000000246 R12: 00007f547e84a4ac
R13: 00007ffd79c2e43f R14: 00007f547df69300 R15: 0000000000022000
Code: c7 40 4c f3 f3 f3 f3 e8 7f d9 f0 ff 49 8d bd b8 02 00 00 48 89 f8 48 c1 e8 03 80 3c 18 00 0f 85 a1 03 00 00 49 8b 9d b8 02 00 00 <48> 85 db 49 0f 44 dd e8 54 d9 f0 ff 48 b8 00 00 00 00 00 fc ff 
----------------
Code disassembly (best guess):
   0:	c7 40 4c f3 f3 f3 f3 	movl   $0xf3f3f3f3,0x4c(%rax)
   7:	e8 7f d9 f0 ff       	callq  0xfff0d98b
   c:	49 8d bd b8 02 00 00 	lea    0x2b8(%r13),%rdi
  13:	48 89 f8             	mov    %rdi,%rax
  16:	48 c1 e8 03          	shr    $0x3,%rax
  1a:	80 3c 18 00          	cmpb   $0x0,(%rax,%rbx,1)
  1e:	0f 85 a1 03 00 00    	jne    0x3c5
  24:	49 8b 9d b8 02 00 00 	mov    0x2b8(%r13),%rbx
* 2b:	48 85 db             	test   %rbx,%rbx <-- trapping instruction
  2e:	49 0f 44 dd          	cmove  %r13,%rbx
  32:	e8 54 d9 f0 ff       	callq  0xfff0d98b
  37:	48                   	rex.W
  38:	b8 00 00 00 00       	mov    $0x0,%eax
  3d:	00 fc                	add    %bh,%ah
  3f:	ff                   	.byte 0xff

Crashes (16):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/06/18 08:41 linux-4.14.y 84bae26850e3 8f633d84 .config console log report syz C ci2-linux-4-14 INFO: task hung in __do_page_fault
2022/06/12 20:35 linux-4.14.y b8f3be299d51 0d5abf15 .config console log report syz C ci2-linux-4-14 INFO: task hung in __do_page_fault
2022/05/15 07:59 linux-4.14.y 569d1abf9402 744a39e2 .config console log report syz C ci2-linux-4-14 INFO: task hung in __do_page_fault
2022/04/24 02:22 linux-4.14.y 15a1c6b6f516 131df97d .config console log report syz C ci2-linux-4-14 INFO: task hung in __do_page_fault
2022/03/30 00:42 linux-4.14.y af1af6ebca0e 6bdac766 .config console log report syz C ci2-linux-4-14 INFO: task hung in __do_page_fault
2022/02/22 15:05 linux-4.14.y a35d65bedfbc 6e821dbf .config console log report syz C ci2-linux-4-14 INFO: task hung in __do_page_fault
2022/02/12 17:55 linux-4.14.y 8034e99d1a01 8b9ca619 .config console log report syz C ci2-linux-4-14 INFO: task hung in __do_page_fault
2022/02/12 10:32 linux-4.14.y 8034e99d1a01 8b9ca619 .config console log report syz C ci2-linux-4-14 INFO: task hung in __do_page_fault
2022/02/10 15:20 linux-4.14.y 21ad423fe521 0b33604d .config console log report syz C ci2-linux-4-14 INFO: task hung in __do_page_fault
2022/02/09 18:07 linux-4.14.y 21ad423fe521 0b33604d .config console log report syz C ci2-linux-4-14 INFO: task hung in __do_page_fault
2022/02/02 15:33 linux-4.14.y b86ee2b7ae42 4ebb2798 .config console log report syz C ci2-linux-4-14 INFO: task hung in __do_page_fault
2019/04/19 07:51 linux-4.14.y 58b454ebf81e b0e8efcb .config console log report syz C ci2-linux-4-14
2022/12/16 16:07 linux-4.14.y c4215ee4771b 05494336 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 INFO: task hung in __do_page_fault
2020/06/08 10:50 linux-4.14.y c6db52a88798 7604bb03 .config console log report ci2-linux-4-14
2020/01/21 10:14 linux-4.14.y c1141b3aab36 8eda0b95 .config console log report ci2-linux-4-14
2020/01/11 00:42 linux-4.14.y b0cdffaa546e 532ec44e .config console log report ci2-linux-4-14
* Struck through repros no longer work on HEAD.