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INFO: task can't die in usb_start_wait_urb

Status: upstream: reported C repro on 2020/08/31 16:47
Reported-by: syzbot+c3df2ca09fe4beef4d67@syzkaller.appspotmail.com
First crash: 676d, last: 659d

Cause bisection: failed (bisect log)

Sample crash report:
INFO: task syz-executor787:6840 can't die for more than 143 seconds.
task:syz-executor787 state:D stack:26864 pid: 6840 ppid:  6833 flags:0x00000004
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1855
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion_timeout+0x15e/0x270 kernel/sched/completion.c:157
 usb_start_wait_urb+0x144/0x2b0 drivers/usb/core/message.c:63
 usb_bulk_msg+0x226/0x550 drivers/usb/core/message.c:254
 do_proc_bulk+0x39b/0x710 drivers/usb/core/devio.c:1231
 proc_bulk drivers/usb/core/devio.c:1268 [inline]
 usbdev_do_ioctl drivers/usb/core/devio.c:2542 [inline]
 usbdev_ioctl+0x586/0x3360 drivers/usb/core/devio.c:2708
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x449659
Code: Bad RIP value.
RSP: 002b:00007f02ac79cdb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000006dac28 RCX: 0000000000449659
RDX: 0000000020000000 RSI: 00000000c0185502 RDI: 0000000000000003
RBP: 00000000006dac20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dac2c
R13: 00007ffe8f1fe93f R14: 00007f02ac79d9c0 R15: 20c49ba5e353f7cf
INFO: task syz-executor787:6840 blocked for more than 143 seconds.
      Not tainted 5.9.0-rc2-next-20200828-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor787 state:D stack:26864 pid: 6840 ppid:  6833 flags:0x00000004
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1855
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion_timeout+0x15e/0x270 kernel/sched/completion.c:157
 usb_start_wait_urb+0x144/0x2b0 drivers/usb/core/message.c:63
 usb_bulk_msg+0x226/0x550 drivers/usb/core/message.c:254
 do_proc_bulk+0x39b/0x710 drivers/usb/core/devio.c:1231
 proc_bulk drivers/usb/core/devio.c:1268 [inline]
 usbdev_do_ioctl drivers/usb/core/devio.c:2542 [inline]
 usbdev_ioctl+0x586/0x3360 drivers/usb/core/devio.c:2708
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x449659
Code: Bad RIP value.
RSP: 002b:00007f02ac79cdb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000006dac28 RCX: 0000000000449659
RDX: 0000000020000000 RSI: 00000000c0185502 RDI: 0000000000000003
RBP: 00000000006dac20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dac2c
R13: 00007ffe8f1fe93f R14: 00007f02ac79d9c0 R15: 20c49ba5e353f7cf

Showing all locks held in the system:
1 lock held by khungtaskd/1173:
 #0: ffffffff89c67640 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5825
1 lock held by in:imklog/6531:
 #0: ffff888098a9c130 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930

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

NMI backtrace for cpu 0
CPU: 0 PID: 1173 Comm: khungtaskd Not tainted 5.9.0-rc2-next-20200828-syzkaller #0
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+0x18f/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline]
 watchdog+0xd89/0xf30 kernel/hung_task.c:339
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3891 Comm: systemd-journal Not tainted 5.9.0-rc2-next-20200828-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3109 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3128 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3183 [inline]
RIP: 0010:__lock_acquire+0x1750/0x5640 kernel/locking/lockdep.c:4426
Code: 74 5d 49 bd 00 00 00 00 00 fc ff df 48 8b 54 24 08 eb 06 49 83 ec 08 74 46 49 8d 7c 24 18 48 89 f8 48 c1 e8 03 42 80 3c 28 00 <0f> 85 43 2a 00 00 49 8b 44 24 18 48 39 c2 0f 84 26 f5 ff ff 49 8d
RSP: 0018:ffffc90004807b00 EFLAGS: 00000046
RAX: 1ffffffff1806a53 RBX: 0000000000003fe4 RCX: ffffffff815a153b
RDX: 62386d250e98b09e RSI: 0000000000000008 RDI: ffffffff8c035298
RBP: ffff888093da49f0 R08: 0000000000000000 R09: ffffffff8c6a59f7
R10: fffffbfff18d4b3e R11: 0000000000000000 R12: ffffffff8c035280
R13: dffffc0000000000 R14: ffff888093da4100 R15: 0000000000000001
FS:  00007ff896ba08c0(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff893f44000 CR3: 000000009398b000 CR4: 00000000001506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 lock_acquire+0x1f1/0xad0 kernel/locking/lockdep.c:5005
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151
 spin_lock include/linux/spinlock.h:354 [inline]
 __alloc_fd+0x34/0x600 fs/file.c:500
 do_sys_openat2+0x134/0x420 fs/open.c:1166
 do_sys_open fs/open.c:1184 [inline]
 __do_sys_open fs/open.c:1192 [inline]
 __se_sys_open fs/open.c:1188 [inline]
 __x64_sys_open+0x119/0x1c0 fs/open.c:1188
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7ff896130840
Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24
RSP: 002b:00007fffa7dee6b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fffa7dee9c0 RCX: 00007ff896130840
RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 0000560b7f41acd0
RBP: 000000000000000d R08: 000000000000ffc0 R09: 00000000ffffffff
R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000560b7f40f040 R14: 00007fffa7dee980 R15: 0000560b7f41aaf0

Crashes (5):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-linux-next-kasan-gce-root 2020/08/29 21:22 linux-next b36c969764ab d5a3ae1f .config log report syz C
ci-upstream-linux-next-kasan-gce-root 2020/08/29 16:22 linux-next b36c969764ab d5a3ae1f .config log report syz C
ci-upstream-linux-next-kasan-gce-root 2020/09/15 08:41 linux-next f965d3ec86fa 6989d6f6 .config log report info
ci-upstream-linux-next-kasan-gce-root 2020/09/06 20:19 linux-next 7a6956579ce6 abf9ba4f .config log report
ci-upstream-linux-next-kasan-gce-root 2020/09/03 16:13 linux-next 7a6956579ce6 abf9ba4f .config log report