syzbot


INFO: task hung in __do_page_fault

Status: public: reported C repro on 2019/04/14 08:51
Reported-by: syzbot+df76c99689b1ae5ce6c8@syzkaller.appspotmail.com
First crash: 2245d, last: 1874d
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 2106d 2048d 0/2 public: reported C repro on 2019/04/14 00:00
linux-4.14 INFO: task hung in __do_page_fault C error 16 705d 2043d 0/1 upstream: reported C repro on 2019/04/19 08:53
upstream INFO: task hung in __do_page_fault (2) C done error 34 1933d 2217d 0/28 closed as invalid on 2022/02/08 10:55
linux-4.19 INFO: task hung in __do_page_fault gfs2 C error 31 687d 1993d 0/1 upstream: reported C repro on 2019/06/08 06:01
android-414 INFO: task hung in __do_page_fault C 7 1883d 2050d 0/1 public: reported C repro on 2019/04/12 00:01
upstream INFO: task hung in __do_page_fault fs 1 2411d 2411d 5/28 fixed on 2018/05/17 10:02

Sample crash report:
INFO: task syz-executor288:2541 blocked for more than 140 seconds.
      Not tainted 4.9.135+ #60
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor288 D28584  2541   2152 0x00000004
 ffff8801c4be17c0 0000000000000000 ffff8801ca1d6e00 ffffffff8302a180
 ffff8801db621018 ffff8801ca2afc50 ffffffff827f93d2 ffff8801ca2afc28
 ffffffff81206ab7 0000000000000000 00ff8801c4be2068 ffff8801db6218f0
Call Trace:
 [<ffffffff827fa8ff>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff8280565c>] rwsem_down_read_failed+0x26c/0x400 kernel/locking/rwsem-xadd.c:260
 [<ffffffff81b69148>] call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 [<ffffffff82803432>] __down_read arch/x86/include/asm/rwsem.h:65 [inline]
 [<ffffffff82803432>] down_read+0x52/0xb0 kernel/locking/rwsem.c:24
 [<ffffffff810b2e6b>] __do_page_fault+0x7db/0xa60 arch/x86/mm/fault.c:1342
 [<ffffffff810b3147>] do_page_fault+0x27/0x30 arch/x86/mm/fault.c:1469
 [<ffffffff8280a675>] page_fault+0x25/0x30 arch/x86/entry/entry_64.S:951

Showing all locks held in the system:
2 locks held by khungtaskd/24:
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131bb4c>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131bb4c>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff813fe314>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/2022:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff82807722>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff81d2b032>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor288/2541:
 #0:  (&mm->mmap_sem){++++++}, at: [<ffffffff810b2e6b>] __do_page_fault+0x7db/0xa60 arch/x86/mm/fault.c:1342
1 lock held by syz-executor288/2542:
 #0:  (&mm->mmap_sem){++++++}, at: [<ffffffff810e6681>] exit_mm kernel/exit.c:480 [inline]
 #0:  (&mm->mmap_sem){++++++}, at: [<ffffffff810e6681>] do_exit+0x3c1/0x29d0 kernel/exit.c:820
1 lock held by syz-executor288/2543:
 #0:  (&mm->mmap_sem){++++++}, at: [<ffffffff810e6681>] exit_mm kernel/exit.c:480 [inline]
 #0:  (&mm->mmap_sem){++++++}, at: [<ffffffff810e6681>] do_exit+0x3c1/0x29d0 kernel/exit.c:820

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

NMI backtrace for cpu 1
CPU: 1 PID: 24 Comm: khungtaskd Not tainted 4.9.135+ #60
 ffff8801d9907d08 ffffffff81b36bf9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff81098330 ffff8801d9907d40
 ffffffff81b41d09 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81b36bf9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b36bf9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81b41d09>] nmi_cpu_backtrace.cold.0+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81b41c9c>] nmi_trigger_cpumask_backtrace+0x12c/0x151 lib/nmi_backtrace.c:60
 [<ffffffff81098434>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff8131c0dd>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff8131c0dd>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8131c0dd>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8131c0dd>] watchdog+0x6ad/0xa20 kernel/hung_task.c:239
 [<ffffffff811428dd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff8280981c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 2544 Comm: syz-executor288 Not tainted 4.9.135+ #60
task: ffff8801c4be4740 task.stack: ffff8801c9cb0000
RIP: 0010:[<ffffffff81205761>] c [<ffffffff81205761>] mark_lock+0x1/0x1290 kernel/locking/lockdep.c:3032
RSP: 0018:ffff8801c9cb7af8  EFLAGS: 00000002
RAX: 0000000000000004 RBX: 0000000000000000 RCX: 1ffff1003897ca02
RDX: 0000000000000006 RSI: ffff8801c4be4ff0 RDI: ffff8801c4be4740
RBP: ffff8801c9cb7b48 R08: ffff8801c4be5010 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801c4be4ff0
R13: ffffed003897c9fd R14: ffff8801c4be4740 R15: dffffc0000000000
FS:  00007fc08a2be700(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc160e55fe0 CR3: 00000001ca5ac000 CR4: 00000000001606b0
Stack:
 ffff8801c9cb7b48c ffffffff81206ab7c ffff8801ca3de060c ffff8801c4be4fe8c
 0000000600000007c ffff8801c4be4740c ffffffff8280209bc 1ffff10039396f72c
 0000000000000246c ffff8801c9cb7bb0c ffff8801c9cb7b68c ffffffff81206eabc
Call Trace:
 [<ffffffff81206eab>] __trace_hardirqs_on_caller kernel/locking/lockdep.c:2689 [inline]
 [<ffffffff81206eab>] trace_hardirqs_on_caller+0x38b/0x590 kernel/locking/lockdep.c:2736
 [<ffffffff812070bd>] trace_hardirqs_on+0xd/0x10 kernel/locking/lockdep.c:2743
 [<ffffffff8280209b>] __mutex_unlock_common_slowpath kernel/locking/mutex.c:753 [inline]
 [<ffffffff8280209b>] __mutex_unlock_slowpath+0x25b/0x3c0 kernel/locking/mutex.c:765
 [<ffffffff82802209>] mutex_unlock+0x9/0x10 kernel/locking/mutex.c:437
 [<ffffffff813d98aa>] perf_mmap+0x64a/0x1430 kernel/events/core.c:5278
 [<ffffffff814b417c>] mmap_region+0x80c/0xf90 mm/mmap.c:1726
 [<ffffffff814b4e3d>] do_mmap+0x53d/0xbb0 mm/mmap.c:1505
 [<ffffffff81469e48>] do_mmap_pgoff include/linux/mm.h:2032 [inline]
 [<ffffffff81469e48>] vm_mmap_pgoff+0x168/0x1b0 mm/util.c:329
 [<ffffffff814af4ee>] SYSC_mmap_pgoff mm/mmap.c:1555 [inline]
 [<ffffffff814af4ee>] SyS_mmap_pgoff+0xfe/0x1b0 mm/mmap.c:1513
 [<ffffffff8105d376>] SYSC_mmap arch/x86/kernel/sys_x86_64.c:96 [inline]
 [<ffffffff8105d376>] SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:87
 [<ffffffff810056ef>] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
 [<ffffffff82809653>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: c16 c04 c03 c85 cc0 c0f c84 cc6 ca8 c1f c00 c48 c83 cc4 c40 c31 cc0 c5b c41 c5c c41 c5d c41 c5e c41 c5f c5d cc3 c4c c89 cff ce8 c36 cd8 c2e c00 ceb cd7 c0f c1f c40 c00 c55 c<4c> c8d c46 c20 c89 cd1 c48 cb8 c00 c00 c00 c00 c00 cfc cff cdf c48 c89 ce5 c41 c57 c

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/10/27 00:13 https://android.googlesource.com/kernel/common android-4.9 322089173588 a8292de9 .config console log report syz C ci-android-49-kasan-gce-root
2019/10/05 05:14 https://android.googlesource.com/kernel/common android-4.9 7fe05eede1c8 f3f7d9c8 .config console log report ci-android-49-kasan-gce-root
2019/04/18 22:27 https://android.googlesource.com/kernel/common android-4.9 5d68df32998c b0e8efcb .config console log report ci-android-49-kasan-gce-root
2018/10/11 08:00 https://android.googlesource.com/kernel/common android-4.9 38f2b4a8c277 5f818b4b .config console log report ci-android-49-kasan-gce-root
2018/09/29 06:40 https://android.googlesource.com/kernel/common android-4.9 4fc79c48d27f 41e4b329 .config console log report ci-android-49-kasan-gce-root
* Struck through repros no longer work on HEAD.