Hello,
syzbot found the following crash on:
HEAD commit: b36fdc6853a3 Merge tag 'gpio-v4.19-2' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=143a64d1400000
kernel config: https://syzkaller.appspot.com/x/.config?x=6c9564cd177daf0c
dashboard link: https://syzkaller.appspot.com/bug?extid=7a7613e5ba9ae7bd15f9
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
Unfortunately, I don't have any reproducer for this crash yet.
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+7a7613e5ba9ae7bd15f9@xxxxxxxxxxxxxxxxxxxxxxxxx
INFO: task syz-executor3:10234 blocked for more than 140 seconds.
Not tainted 4.19.0-rc2+ #3
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3 D23224 10234 7516 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2825 [inline]
__schedule+0x87c/0x1df0 kernel/sched/core.c:3473
schedule+0xfb/0x450 kernel/sched/core.c:3517
schedule_timeout+0x1cc/0x260 kernel/time/timer.c:1780
do_wait_for_common kernel/sched/completion.c:83 [inline]
__wait_for_common kernel/sched/completion.c:104 [inline]
wait_for_common kernel/sched/completion.c:115 [inline]
wait_for_completion_timeout+0x45f/0x960 kernel/sched/completion.c:155
usb_start_wait_urb+0x18b/0x360 drivers/usb/core/message.c:62
usb_bulk_msg+0x22e/0x550 drivers/usb/core/message.c:253
proc_bulk+0x590/0xaa0 drivers/usb/core/devio.c:1193
usbdev_do_ioctl+0x19fc/0x3b30 drivers/usb/core/devio.c:2401
usbdev_ioctl+0x25/0x30 drivers/usb/core/devio.c:2551
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:501 [inline]
do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685
ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702
__do_sys_ioctl fs/ioctl.c:709 [inline]
__se_sys_ioctl fs/ioctl.c:707 [inline]
__x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457099
Code: Bad RIP value.
RSP: 002b:00007f408a01ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f408a01f6d4 RCX: 0000000000457099
RDX: 0000000020000240 RSI: 00000000c0185502 RDI: 0000000000000003
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004cebc0 R14: 00000000004c503e R15: 0000000000000000
Showing all locks held in the system:
1 lock held by khungtaskd/792:
#0: 00000000935370f1 (rcu_read_lock){....}, at:
debug_show_all_locks+0xd0/0x428 kernel/locking/lockdep.c:4436
1 lock held by rsyslogd/4545:
2 locks held by getty/4666:
#0: 000000001c78bb1f (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353
#1: 00000000fd476690 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140
2 locks held by getty/4667:
#0: 000000003636bd05 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353
#1: 0000000080b0e131 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140
2 locks held by getty/4668:
#0: 00000000784da20e (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353
#1: 00000000f35d11ec (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140
2 locks held by getty/4669:
#0: 0000000050e62864 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353
#1: 0000000013be2de2 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140
2 locks held by getty/4670:
#0: 0000000076405ad8 (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353
#1: 000000006c5d932d (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140
2 locks held by getty/4671:
#0: 00000000a94de6ea (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353
#1: 000000004906f867 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140
2 locks held by getty/4672:
#0: 00000000664d51ab (&tty->ldisc_sem){++++}, at:
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:353
#1: 00000000cdc5bd8f (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 792 Comm: khungtaskd Not tainted 4.19.0-rc2+ #3
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+0x1c9/0x2b4 lib/dump_stack.c:113
nmi_cpu_backtrace.cold.3+0x48/0x88 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x151/0x192 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:144 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline]
watchdog+0xb39/0x1040 kernel/hung_task.c:265
kthread+0x35a/0x420 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.19.0-rc2+ #3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__wrmsr arch/x86/include/asm/msr.h:105 [inline]
RIP: 0010:native_apic_msr_eoi_write+0xf/0x20 arch/x86/include/asm/apic.h:214
Code: ff ff e9 13 ff ff ff e8 9f 8f 87 00 e9 de fe ff ff e8 35 58 13 00 90
90 90 90 90 55 31 c0 b9 0b 08 00 00 89 c2 48 89 e5 0f 30 <5d> c3 0f 1f 44
00 00 66 2e 0f 1f 84 00 00 00 00 00 c3 0f 1f 44 00
RSP: 0018:ffff8801db107e90 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 1ffff1003b620fd4 RCX: 000000000000080b
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000000000b0
RBP: ffff8801db107e90 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff87f2d300
R13: ffff8801db107fc0 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 00000001b7c96000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
apic_eoi arch/x86/include/asm/apic.h:402 [inline]
ack_APIC_irq arch/x86/include/asm/apic.h:448 [inline]
smp_reschedule_interrupt+0xe4/0x5e0 arch/x86/kernel/smp.c:262
reschedule_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:888
</IRQ>
RIP: 0010:native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:57
Code: c7 48 89 45 d8 e8 fa fc e4 fa 48 8b 45 d8 e9 d2 fe ff ff 48 89 df e8
e9 fc e4 fa eb 8a 90 90 90 90 90 90 90 55 48 89 e5 fb f4 <5d> c3 0f 1f 84
00 00 00 00 00 55 48 89 e5 f4 5d c3 90 90 90 90 90
RSP: 0018:ffff8801d9f27c30 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff02
RAX: dffffc0000000000 RBX: 1ffff1003b3e4f8a RCX: 0000000000000000
RDX: 1ffffffff10237c8 RSI: 0000000000000001 RDI: ffffffff8811be40
RBP: ffff8801d9f27c30 R08: ffff8801d9f1a380 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: ffff8801d9f27cf0 R14: 0000000000000001 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
default_idle+0xc2/0x410 arch/x86/kernel/process.c:498
arch_cpu_idle+0x10/0x20 arch/x86/kernel/process.c:489
default_idle_call+0x6d/0x90 kernel/sched/idle.c:93
cpuidle_idle_call kernel/sched/idle.c:153 [inline]
do_idle+0x3aa/0x580 kernel/sched/idle.c:262
cpu_startup_entry+0x10c/0x120 kernel/sched/idle.c:368
start_secondary+0x433/0x5d0 arch/x86/kernel/smpboot.c:271
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242
---
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