INFO: task syz-executor.1:20069 blocked for more than 143 seconds. Not tainted 5.14.0-rc6-next-20210820-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:22224 pid:20069 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4756 [inline] __schedule+0x943/0x2700 kernel/sched/core.c:6029 schedule+0xd7/0x280 kernel/sched/core.c:6108 fsnotify_sb_delete+0x3fc/0x4e0 fs/notify/fsnotify.c:97 generic_shutdown_super+0xb7/0x380 fs/super.c:456 kill_anon_super fs/super.c:1057 [inline] kill_litter_super+0x6e/0xa0 fs/super.c:1066 deactivate_locked_super+0x94/0x160 fs/super.c:335 deactivate_super+0xb5/0xe0 fs/super.c:366 cleanup_mnt+0x3a3/0x540 fs/namespace.c:1137 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x467a47 RSP: 002b:00007fffb47ca4a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000467a47 RDX: 00007fffb47ca57a RSI: 0000000000000002 RDI: 00007fffb47ca570 RBP: 00007fffb47ca570 R08: 00000000ffffffff R09: 00007fffb47ca340 R10: 00000000020bf8e3 R11: 0000000000000246 R12: 00000000004bee90 R13: 00007fffb47cb640 R14: 00000000020bf810 R15: 00007fffb47cb680 INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 PID: 26 Comm: khungtaskd Not tainted 5.14.0-rc6-next-20210820-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:254 [inline] watchdog+0xccb/0xef0 kernel/hung_task.c:339 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2964 Comm: systemd-journal Not tainted 5.14.0-rc6-next-20210820-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:49 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:342 [inline] RIP: 0010:deref_stack_reg+0x81/0x160 arch/x86/kernel/unwind_orc.c:352 Code: 85 c3 00 00 00 49 8d 7c 24 10 4d 8b 6c 24 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 94 00 00 00 <49> 39 ed 49 8b 44 24 10 77 13 48 39 e8 76 0e 48 8d 55 08 48 39 d0 RSP: 0018:ffffc900024cf598 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffffc900024cf700 RCX: 0000000000000000 RDX: 1ffff92000499eda RSI: ffffc900024cfa38 RDI: ffffc900024cf6d0 RBP: ffffc900024cfa38 R08: ffffffff8df2260c R09: 0000000000000001 R10: fffff52000499ee3 R11: 0000000000086089 R12: ffffc900024cf6c0 R13: ffffc900024c8000 R14: ffffc900024cf6c0 R15: ffffc900024cf6f4 FS: 00007fe935a628c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe9326cec00 CR3: 000000001c8a2000 CR4: 00000000001526e0 Call Trace: unwind_next_frame+0x13e0/0x1ce0 arch/x86/kernel/unwind_orc.c:587 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:121 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_record_aux_stack+0xed/0x120 mm/kasan/generic.c:348 task_work_add+0x3a/0x190 kernel/task_work.c:38 fput_many.part.0+0xbb/0x170 fs/file_table.c:341 fput_many fs/file_table.c:336 [inline] fput+0x3f/0x50 fs/file_table.c:357 path_openat+0x1a56/0x28b0 fs/namei.c:3570 do_filp_open+0x1aa/0x400 fs/namei.c:3588 do_sys_openat2+0x16d/0x4e0 fs/open.c:1204 do_sys_open fs/open.c:1220 [inline] __do_sys_open fs/open.c:1228 [inline] __se_sys_open fs/open.c:1224 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1224 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fe934ff1840 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:00007ffc62a2cb78 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffc62a2ce80 RCX: 00007fe934ff1840 RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 00005606b14324c0 RBP: 000000000000000d R08: 000000000000ffc0 R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff R13: 00005606b1425040 R14: 00007ffc62a2ce40 R15: 00005606b14322e0 ---------------- Code disassembly (best guess): 0: 85 c3 test %eax,%ebx 2: 00 00 add %al,(%rax) 4: 00 49 8d add %cl,-0x73(%rcx) 7: 7c 24 jl 0x2d 9: 10 4d 8b adc %cl,-0x75(%rbp) c: 6c insb (%dx),%es:(%rdi) d: 24 08 and $0x8,%al f: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 16: fc ff df 19: 48 89 fa mov %rdi,%rdx 1c: 48 c1 ea 03 shr $0x3,%rdx 20: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 24: 0f 85 94 00 00 00 jne 0xbe * 2a: 49 39 ed cmp %rbp,%r13 <-- trapping instruction 2d: 49 8b 44 24 10 mov 0x10(%r12),%rax 32: 77 13 ja 0x47 34: 48 39 e8 cmp %rbp,%rax 37: 76 0e jbe 0x47 39: 48 8d 55 08 lea 0x8(%rbp),%rdx 3d: 48 39 d0 cmp %rdx,%rax