INFO: task syz-executor109:16912 blocked for more than 140 seconds. Not tainted 4.14.274-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor109 D28912 16912 7968 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x1e6/0x350 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:66 [inline] down_read+0x44/0x80 kernel/locking/rwsem.c:26 __do_page_fault+0x7b8/0xad0 arch/x86/mm/fault.c:1378 page_fault+0x45/0x50 arch/x86/entry/entry_64.S:1123 RIP: 5367041c:0x7ffc02057030 RSP: 0064:0000000000000032 EFLAGS: 7ffc02057010 INFO: task syz-executor109:16913 blocked for more than 140 seconds. Not tainted 4.14.274-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor109 D29112 16913 7968 0x80000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x1e6/0x350 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:66 [inline] down_read+0x44/0x80 kernel/locking/rwsem.c:26 exit_mm kernel/exit.c:511 [inline] do_exit+0x598/0x2850 kernel/exit.c:855 do_group_exit+0x100/0x2e0 kernel/exit.c:965 get_signal+0x38d/0x1ca0 kernel/signal.c:2412 do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:792 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f10535e8b39 RSP: 002b:00007f105359a318 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f1053670408 RCX: 00007f10535e8b39 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f1053670408 RBP: 00007f1053670400 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f105363e074 R13: 00007ffc02056f5f R14: 00007f105359a400 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1532: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 1 lock held by syz-executor109/16912: #0: (&mm->mmap_sem){++++}, at: [] __do_page_fault+0x7b8/0xad0 arch/x86/mm/fault.c:1378 1 lock held by syz-executor109/16913: #0: (&mm->mmap_sem){++++}, at: [] exit_mm kernel/exit.c:511 [inline] #0: (&mm->mmap_sem){++++}, at: [] do_exit+0x598/0x2850 kernel/exit.c:855 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1532 Comm: khungtaskd Not tainted 4.14.274-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 16914 Comm: syz-executor109 Not tainted 4.14.274-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff88809aa10580 task.stack: ffff888093a08000 RIP: 0010:__lock_release kernel/locking/lockdep.c:3804 [inline] RIP: 0010:lock_release+0x528/0x870 kernel/locking/lockdep.c:4017 RSP: 0018:ffff888093a0fb00 EFLAGS: 00000806 RAX: 0000000000000000 RBX: 1ffff11012741f63 RCX: 1ffff110135421c6 RDX: 1ffff110135421c0 RSI: 0000000000000002 RDI: ffff88809aa10580 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: ffff88809aa10580 R12: 7c16b83a7c1411fc R13: 0000000000000003 R14: ffff88809aa10580 R15: 0000000000000002 FS: 00007f1053579700(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1e1958c000 CR3: 000000009adb2000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __mutex_unlock_slowpath+0x75/0x770 kernel/locking/mutex.c:1018 perf_mmap+0x635/0x1390 kernel/events/core.c:5436 call_mmap include/linux/fs.h:1785 [inline] mmap_region+0xa1a/0x1220 mm/mmap.c:1717 do_mmap+0x5b3/0xcb0 mm/mmap.c:1495 do_mmap_pgoff include/linux/mm.h:2185 [inline] vm_mmap_pgoff+0x14e/0x1a0 mm/util.c:333 SYSC_mmap_pgoff mm/mmap.c:1545 [inline] SyS_mmap_pgoff+0x249/0x510 mm/mmap.c:1503 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f10535e8b39 RSP: 002b:00007f1053579308 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f1053670418 RCX: 00007f10535e8b39 RDX: 0000000000000000 RSI: 0000000000002000 RDI: 0000000020395000 RBP: 00007f1053670410 R08: 0000000000000003 R09: 0000000000000000 R10: 0000000000000011 R11: 0000000000000246 R12: 00007f105363e074 R13: 00007ffc02056f5f R14: 00007f1053579400 R15: 0000000000022000 Code: 0f ad c0 7e 0f 85 42 fc ff ff e8 c0 49 be ff e9 38 fc ff ff 48 b8 00 00 00 00 00 fc ff df 48 8b 54 24 08 48 c1 ea 03 0f b6 04 02 <84> c0 74 08 3c 03 0f 8e de 02 00 00 45 8d 4f ff 45 39 8e 80 08 ---------------- Code disassembly (best guess), 4 bytes skipped: 0: 0f 85 42 fc ff ff jne 0xfffffc48 6: e8 c0 49 be ff callq 0xffbe49cb b: e9 38 fc ff ff jmpq 0xfffffc48 10: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 17: fc ff df 1a: 48 8b 54 24 08 mov 0x8(%rsp),%rdx 1f: 48 c1 ea 03 shr $0x3,%rdx 23: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax * 27: 84 c0 test %al,%al <-- trapping instruction 29: 74 08 je 0x33 2b: 3c 03 cmp $0x3,%al 2d: 0f 8e de 02 00 00 jle 0x311 33: 45 8d 4f ff lea -0x1(%r15),%r9d 37: 45 rex.RB 38: 39 .byte 0x39 39: 8e .byte 0x8e 3a: 80 .byte 0x80 3b: 08 .byte 0x8