INFO: task syz-executor796:8213 can't die for more than 143 seconds. task:syz-executor796 state:D stack:28240 pid: 8213 ppid: 6877 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: 0033:0x44d089 Code: Bad RIP value. RSP: 002b:00007fd456e00db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000006dec58 RCX: 000000000044d089 RDX: 0000000020000000 RSI: 00000000c0185502 RDI: 0000000000000003 RBP: 00000000006dec50 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dec5c R13: 00007ffd794cef4f R14: 00007fd456e019c0 R15: 0000000000000064 INFO: task syz-executor796:8213 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-executor796 state:D stack:28240 pid: 8213 ppid: 6877 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: 0033:0x44d089 Code: Bad RIP value. RSP: 002b:00007fd456e00db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000006dec58 RCX: 000000000044d089 RDX: 0000000020000000 RSI: 00000000c0185502 RDI: 0000000000000003 RBP: 00000000006dec50 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dec5c R13: 00007ffd794cef4f R14: 00007fd456e019c0 R15: 0000000000000064 Showing all locks held in the system: 1 lock held by khungtaskd/1166: #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/6552: #0: ffff88809b9398b0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 2 locks held by kworker/u4:1/6915: 1 lock held by syz-executor796/24309: #0: ffff8880ae735f98 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1292 [inline] #0: ffff8880ae735f98 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x232/0x21e0 kernel/sched/core.c:4445 1 lock held by syz-executor796/24323: #0: ffff8880ae735f98 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1292 [inline] #0: ffff8880ae735f98 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x232/0x21e0 kernel/sched/core.c:4445 1 lock held by syz-executor796/24332: #0: ffff8880ae735f98 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1292 [inline] #0: ffff8880ae735f98 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x232/0x21e0 kernel/sched/core.c:4445 1 lock held by syz-executor796/24342: 1 lock held by syz-executor796/24344: #0: ffff8880ae735f98 (&rq->lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1292 [inline] #0: ffff8880ae735f98 (&rq->lock){-.-.}-{2:2}, at: __schedule+0x232/0x21e0 kernel/sched/core.c:4445 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1166 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: 6875 Comm: syz-executor796 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:kasan_mem_to_shadow include/linux/kasan.h:29 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:134 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:165 [inline] RIP: 0010:check_memory_region_inline mm/kasan/generic.c:183 [inline] RIP: 0010:check_memory_region+0x52/0x180 mm/kasan/generic.c:192 Code: 39 c7 0f 86 05 01 00 00 49 83 e9 01 48 89 fd 48 b8 00 00 00 00 00 fc ff df 4d 89 ca 48 c1 ed 03 49 c1 ea 03 48 01 c5 49 01 c2 <48> 89 e8 49 8d 5a 01 48 89 da 48 29 ea 48 83 fa 10 7e 63 41 89 eb RSP: 0018:ffffc9000531f768 EFLAGS: 00000282 RAX: dffffc0000000000 RBX: ffff888082863250 RCX: ffffffff83b3d99e RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff888082863250 RBP: ffffed101050c64a R08: 0000000000000001 R09: ffff888082863253 R10: ffffed101050c64a R11: 0000000000000000 R12: ffff888082863250 R13: ffff8880877c7c48 R14: ffff8880828630d0 R15: ffff8880877aabe0 FS: 0000000001a24880(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000400200 CR3: 00000000a90fd000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: _atomic_dec_and_lock+0x1e/0x100 include/linux/instrumented.h:101 iput.part.0+0x67/0x850 fs/inode.c:1670 iput+0x58/0x70 fs/inode.c:1668 dentry_unlink_inode+0x2b1/0x3d0 fs/dcache.c:374 __dentry_kill+0x3c0/0x640 fs/dcache.c:579 shrink_dentry_list+0x144/0x480 fs/dcache.c:1141 shrink_dcache_parent+0x219/0x3c0 fs/dcache.c:1568 d_invalidate fs/dcache.c:1677 [inline] d_invalidate+0x13f/0x280 fs/dcache.c:1662 proc_invalidate_siblings_dcache+0x43b/0x600 fs/proc/inode.c:150 release_task+0xc63/0x14d0 kernel/exit.c:221 wait_task_zombie kernel/exit.c:1088 [inline] wait_consider_task+0x2fb3/0x3b20 kernel/exit.c:1315 do_wait_thread kernel/exit.c:1378 [inline] do_wait+0x36a/0x9e0 kernel/exit.c:1449 kernel_wait4+0x14c/0x260 kernel/exit.c:1604 __do_sys_wait4+0x13f/0x150 kernel/exit.c:1632 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x4083ea Code: c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 8b 05 0e d0 2d 00 85 c0 75 36 45 31 d2 48 63 d2 48 63 ff b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 d0 ff ff ff f7 RSP: 002b:00007ffd794cefc8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d RAX: ffffffffffffffda RBX: 00000000000025bc RCX: 00000000004083ea RDX: 0000000040000001 RSI: 00007ffd794cefe0 RDI: ffffffffffffffff RBP: 00000000000bedbe R08: 0000000000000001 R09: 0000000001a24880 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd794cf010 R13: 000000000040a140 R14: 0000000000000000 R15: 0000000000000000