INFO: task syz-executor402:8197 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor402 D29600 8197 8078 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1016 [inline] __mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078 mutex_lock_double kernel/events/core.c:10470 [inline] __perf_event_ctx_lock_double kernel/events/core.c:10529 [inline] __do_sys_perf_event_open kernel/events/core.c:10784 [inline] __se_sys_perf_event_open+0x1863/0x2720 kernel/events/core.c:10549 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fd76da75a99 Code: Bad RIP value. RSP: 002b:00007fd76da27318 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007fd76dafd3e8 RCX: 00007fd76da75a99 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000020000000 RBP: 00007fd76dafd3e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 00007fd76dafd3ec R13: 00007ffda3c4f79f R14: 00007fd76da27400 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1571: #0: 0000000058914efa (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7758: #0: 00000000029ead48 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 2 locks held by syz-executor402/8197: #0: 000000007fd7c365 (&cpuctx_mutex){+.+.}, at: mutex_lock_double kernel/events/core.c:10469 [inline] #0: 000000007fd7c365 (&cpuctx_mutex){+.+.}, at: __perf_event_ctx_lock_double kernel/events/core.c:10529 [inline] #0: 000000007fd7c365 (&cpuctx_mutex){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10784 [inline] #0: 000000007fd7c365 (&cpuctx_mutex){+.+.}, at: __se_sys_perf_event_open+0x1856/0x2720 kernel/events/core.c:10549 #1: 000000007fd7c365 (&cpuctx_mutex/1){+.+.}, at: mutex_lock_double kernel/events/core.c:10470 [inline] #1: 000000007fd7c365 (&cpuctx_mutex/1){+.+.}, at: __perf_event_ctx_lock_double kernel/events/core.c:10529 [inline] #1: 000000007fd7c365 (&cpuctx_mutex/1){+.+.}, at: __do_sys_perf_event_open kernel/events/core.c:10784 [inline] #1: 000000007fd7c365 (&cpuctx_mutex/1){+.+.}, at: __se_sys_perf_event_open+0x1863/0x2720 kernel/events/core.c:10549 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1571 Comm: khungtaskd Not tainted 4.19.211-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+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4694 Comm: systemd-journal Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_release kernel/locking/lockdep.c:3705 [inline] RIP: 0010:lock_release+0x35e/0x8b0 kernel/locking/lockdep.c:3927 Code: 03 80 3c 11 00 0f 85 cc 04 00 00 49 8d be 78 08 00 00 4c 8b 28 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 be 04 00 00 4d 89 ae 78 08 00 00 8d 55 01 44 89 fe 4c 89 f7 RSP: 0018:ffff8880a0fa7e48 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffffffff8d243760 RCX: 1ffff110141f3dd1 RDX: 1ffff110141f3dcf RSI: ffffffff89f85fa0 RDI: ffff8880a0f9ee78 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff110141f4fcc R13: 0000000000000000 R14: ffff8880a0f9e600 R15: 0000000000000001 FS: 00007fae6dda98c0(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fae6b178000 CR3: 00000000a082c000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_release include/linux/rcupdate.h:247 [inline] rcu_read_unlock include/linux/rcupdate.h:681 [inline] __task_pid_nr_ns+0x28c/0x4c0 kernel/pid.c:432 task_tgid_vnr include/linux/sched.h:1305 [inline] __ia32_sys_getpid+0x1a/0x20 kernel/sys.c:890 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fae6d041f17 Code: ff ff ff 48 8b 4d a0 0f b7 51 fe 48 8b 4d a8 66 89 54 08 fe e9 1a ff ff ff 66 2e 0f 1f 84 00 00 00 00 00 b8 27 00 00 00 0f 05 0f 1f 84 00 00 00 00 00 b8 6e 00 00 00 0f 05 c3 0f 1f 84 00 00 RSP: 002b:00007fff0b3b0968 EFLAGS: 00000202 ORIG_RAX: 0000000000000027 RAX: ffffffffffffffda RBX: 000055caaf9991e0 RCX: 00007fae6d041f17 RDX: 00000000000000e0 RSI: 0000000000000000 RDI: 000055caaf9991e0 RBP: 0000000000000000 R08: 000055caaf998a7c R09: 000055caaf99925c R10: 000055caaf9991e0 R11: 0000000000000202 R12: 0000000000001256 R13: 00007fff0b3b0aa8 R14: 000055caaef8c958 R15: 0005e1176d415ec7 ---------------- Code disassembly (best guess): 0: 03 80 3c 11 00 0f add 0xf00113c(%rax),%eax 6: 85 cc test %ecx,%esp 8: 04 00 add $0x0,%al a: 00 49 8d add %cl,-0x73(%rcx) d: be 78 08 00 00 mov $0x878,%esi 12: 4c 8b 28 mov (%rax),%r13 15: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 1c: fc ff df 1f: 48 89 fa mov %rdi,%rdx 22: 48 c1 ea 03 shr $0x3,%rdx 26: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) * 2a: 0f 85 be 04 00 00 jne 0x4ee <-- trapping instruction 30: 4d 89 ae 78 08 00 00 mov %r13,0x878(%r14) 37: 8d 55 01 lea 0x1(%rbp),%edx 3a: 44 89 fe mov %r15d,%esi 3d: 4c 89 f7 mov %r14,%rdi