INFO: task syz-executor380:3423 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-executor380 D28648 3423 8109 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 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x20a/0x390 kernel/locking/rwsem-xadd.c:309 call_rwsem_down_read_failed+0x14/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0x44/0x80 kernel/locking/rwsem.c:26 __do_page_fault+0x97f/0xd60 arch/x86/mm/fault.c:1348 page_fault+0x1e/0x30 arch/x86/entry/entry_64.S:1205 RIP: 0033:0x7f4326ba0468 Code: Bad RIP value. RSP: 002b:00007ffcbec3e978 EFLAGS: 00010202 RAX: 00007f4326bd3bb0 RBX: 00007f4326bd2198 RCX: 0000000000000001 RDX: 00007f4326b0de60 RSI: 0000000000000000 RDI: 00007f4326bd3bb0 RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffc0000000a R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f4326bdb180 R15: 0000000000000001 INFO: task syz-executor380:3444 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-executor380 D28128 3444 8109 0x80000004 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 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x20a/0x390 kernel/locking/rwsem-xadd.c:309 call_rwsem_down_read_failed+0x14/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:83 [inline] down_read+0x44/0x80 kernel/locking/rwsem.c:26 exit_mm kernel/exit.c:512 [inline] do_exit+0x6e4/0x2be0 kernel/exit.c:857 do_group_exit+0x125/0x310 kernel/exit.c:967 get_signal+0x3f2/0x1f70 kernel/signal.c:2589 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:799 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f4326b52ce9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 91 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f43262d4218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f4326bd44b8 RCX: 00007f4326b52ce9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f4326bd44b8 RBP: 00007f4326bd44b0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4326bd44bc R13: 00007ffcbec3e94f R14: 00007f43262d4300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1571: #0: 000000003c7b458c (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7799: #0: 000000008e8a1fa1 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 1 lock held by syz-executor380/3423: #0: 0000000032c73c31 (&mm->mmap_sem){++++}, at: __do_page_fault+0x97f/0xd60 arch/x86/mm/fault.c:1348 1 lock held by syz-executor380/3428: 1 lock held by syz-executor380/3444: #0: 0000000032c73c31 (&mm->mmap_sem){++++}, at: exit_mm kernel/exit.c:512 [inline] #0: 0000000032c73c31 (&mm->mmap_sem){++++}, at: do_exit+0x6e4/0x2be0 kernel/exit.c:857 2 locks held by kworker/0:1/25239: #0: 000000000d23bd8f ((wq_completion)"rcu_gp"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 0000000029084961 ((work_completion)(&rew.rew_work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 1 lock held by syz-executor380/5072: #0: 0000000091421172 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x152/0x200 mm/util.c:355 2 locks held by syz-executor380/5076: #0: 0000000091421172 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x152/0x200 mm/util.c:355 #1: 000000004e26f6e4 (&event->mmap_mutex){+.+.}, at: perf_mmap+0x693/0x1810 kernel/events/core.c:5713 1 lock held by syz-executor380/5074: #0: 000000005705b783 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x152/0x200 mm/util.c:355 3 locks held by syz-executor380/5078: #0: 000000005705b783 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x152/0x200 mm/util.c:355 #1: 00000000b8deb9e0 (&event->mmap_mutex){+.+.}, at: perf_mmap+0x693/0x1810 kernel/events/core.c:5713 #2: 000000008bc78536 (rcu_preempt_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #2: 000000008bc78536 (rcu_preempt_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited+0x256/0x6f0 kernel/rcu/tree_exp.h:667 1 lock held by syz-executor380/5077: #0: 00000000d9c0bd2c (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x152/0x200 mm/util.c:355 2 locks held by syz-executor380/5079: #0: 00000000d9c0bd2c (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x152/0x200 mm/util.c:355 #1: 0000000088895713 (&event->mmap_mutex){+.+.}, at: perf_mmap+0x693/0x1810 kernel/events/core.c:5713 1 lock held by syz-executor380/5080: #0: 000000007b5051dc (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x152/0x200 mm/util.c:355 2 locks held by syz-executor380/5083: #0: 000000007b5051dc (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x152/0x200 mm/util.c:355 #1: 0000000088d26c81 (&event->mmap_mutex){+.+.}, at: perf_mmap+0x693/0x1810 kernel/events/core.c:5713 1 lock held by syz-executor380/5081: #0: 00000000915cd6c7 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x152/0x200 mm/util.c:355 2 locks held by syz-executor380/5082: #0: 00000000915cd6c7 (&mm->mmap_sem){++++}, at: vm_mmap_pgoff+0x152/0x200 mm/util.c:355 #1: 000000003f8b7e84 (&event->mmap_mutex){+.+.}, at: perf_mmap+0x693/0x1810 kernel/events/core.c:5713 ============================================= NMI backtrace for cpu 1 CPU: 1 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 25239 Comm: kworker/0:1 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: rcu_gp wait_rcu_exp_gp RIP: 0010:__lock_release kernel/locking/lockdep.c:3684 [inline] RIP: 0010:lock_release+0x268/0x8b0 kernel/locking/lockdep.c:3927 Code: 4c 89 f7 e8 ba 72 ff ff 48 85 c0 0f 84 a9 03 00 00 48 8d 78 24 48 ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 0f b6 0c 11 <48> 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 19 05 00 00 8b RSP: 0018:ffff8880b2c77860 EFLAGS: 00000803 RAX: ffff8880ab5e2b00 RBX: ffffffff8d243760 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffffffff8d3cd720 RDI: ffff8880ab5e2b24 RBP: ffffffff8d3cd720 R08: 0000000000000086 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff1101658ef0f R13: ffffffff83772ee9 R14: ffff8880ab5e2200 R15: 0000000000000004 FS: 0000000000000000(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000100 CR3: 00000000ab1b0000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:158 [inline] _raw_spin_unlock_irqrestore+0x1b/0xe0 kernel/locking/spinlock.c:184 debug_object_deactivate lib/debugobjects.c:568 [inline] debug_object_deactivate+0x1f9/0x2e0 lib/debugobjects.c:529 debug_timer_deactivate kernel/time/timer.c:723 [inline] debug_deactivate kernel/time/timer.c:779 [inline] detach_timer kernel/time/timer.c:824 [inline] detach_if_pending+0x82/0x460 kernel/time/timer.c:843 try_to_del_timer_sync+0xaa/0x110 kernel/time/timer.c:1240 del_timer_sync+0x1a4/0x270 kernel/time/timer.c:1305 schedule_timeout+0x4d7/0xfe0 kernel/time/timer.c:1819 synchronize_sched_expedited_wait kernel/rcu/tree_exp.h:529 [inline] rcu_exp_wait_wake+0x2ff/0x480 kernel/rcu/tree_exp.h:597 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 ---------------- Code disassembly (best guess): 0: 4c 89 f7 mov %r14,%rdi 3: e8 ba 72 ff ff callq 0xffff72c2 8: 48 85 c0 test %rax,%rax b: 0f 84 a9 03 00 00 je 0x3ba 11: 48 8d 78 24 lea 0x24(%rax),%rdi 15: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx 1c: fc ff df 1f: 48 89 f9 mov %rdi,%rcx 22: 48 c1 e9 03 shr $0x3,%rcx 26: 0f b6 0c 11 movzbl (%rcx,%rdx,1),%ecx * 2a: 48 89 fa mov %rdi,%rdx <-- trapping instruction 2d: 83 e2 07 and $0x7,%edx 30: 83 c2 03 add $0x3,%edx 33: 38 ca cmp %cl,%dl 35: 7c 08 jl 0x3f 37: 84 c9 test %cl,%cl 39: 0f 85 19 05 00 00 jne 0x558 3f: 8b .byte 0x8b