INFO: task syz-executor.5:6771 blocked for more than 143 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:28392 pid: 6771 ppid: 6541 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 blk_mq_freeze_queue_wait+0x112/0x160 block/blk-mq.c:178 nbd_add_socket+0x166/0x810 drivers/block/nbd.c:1109 __nbd_ioctl drivers/block/nbd.c:1454 [inline] nbd_ioctl+0x38c/0xb10 drivers/block/nbd.c:1511 blkdev_ioctl+0x37a/0x800 block/ioctl.c:609 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f8edccebae9 RSP: 002b:00007f8eda261188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f8edcdfef60 RCX: 00007f8edccebae9 RDX: 0000000000000005 RSI: 000000000000ab00 RDI: 0000000000000004 RBP: 00007f8edcd45f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe1c345f4f R14: 00007f8eda261300 R15: 0000000000022000 INFO: task syz-executor.5:6774 blocked for more than 143 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:27632 pid: 6774 ppid: 6541 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6382 __mutex_lock_common kernel/locking/mutex.c:680 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740 nbd_ioctl+0x151/0xb10 drivers/block/nbd.c:1504 blkdev_ioctl+0x37a/0x800 block/ioctl.c:609 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f8edccebae9 RSP: 002b:00007f8eda240188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f8edcdff020 RCX: 00007f8edccebae9 RDX: 0000000000000005 RSI: 000000000000ab00 RDI: 0000000000000004 RBP: 00007f8edcd45f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe1c345f4f R14: 00007f8eda240300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8b983b60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 1 lock held by syz-executor.5/6771: #0: ffff88801a589198 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x151/0xb10 drivers/block/nbd.c:1504 1 lock held by syz-executor.5/6774: #0: ffff88801a589198 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x151/0xb10 drivers/block/nbd.c:1504 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.0-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:210 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:295 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 31 Comm: kcompactd1 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__kasan_check_read+0x4/0x10 mm/kasan/shadow.c:31 Code: 39 07 48 85 db 0f 85 6e e2 3a 07 48 83 c4 60 5b 5d 41 5c 41 5d c3 c3 e9 6e e3 3a 07 cc cc cc cc cc cc cc cc cc cc 48 8b 0c 24 <89> f6 31 d2 e9 f3 f9 ff ff 0f 1f 00 48 8b 0c 24 89 f6 ba 01 00 00 RSP: 0018:ffffc90000e6fd78 EFLAGS: 00000002 RAX: 0000000000000282 RBX: 0000000000000001 RCX: ffffffff81594b87 RDX: 1ffff11047fff7ab RSI: 0000000000000008 RDI: ffff8880139e3a00 RBP: ffff8880139e3a00 R08: 0000000000000001 R09: 0000000000000003 R10: fffff520001cdf9e R11: 0000000000000001 R12: ffffc90000e6fe70 R13: ffff88823fffbd48 R14: 0000000000000282 R15: 000000000000005a FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f659621d000 CR3: 000000001fdda000 CR4: 0000000000350ef0 DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] test_ti_thread_flag include/linux/thread_info.h:118 [inline] test_tsk_thread_flag include/linux/sched.h:1984 [inline] signal_pending include/linux/sched/signal.h:380 [inline] signal_pending_state include/linux/sched/signal.h:399 [inline] prepare_to_wait_event+0xe7/0x690 kernel/sched/wait.c:301 kcompactd+0x903/0xf30 mm/compaction.c:2936 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 39 07 cmp %eax,(%rdi) 2: 48 85 db test %rbx,%rbx 5: 0f 85 6e e2 3a 07 jne 0x73ae279 b: 48 83 c4 60 add $0x60,%rsp f: 5b pop %rbx 10: 5d pop %rbp 11: 41 5c pop %r12 13: 41 5d pop %r13 15: c3 retq 16: c3 retq 17: e9 6e e3 3a 07 jmpq 0x73ae38a 1c: cc int3 1d: cc int3 1e: cc int3 1f: cc int3 20: cc int3 21: cc int3 22: cc int3 23: cc int3 24: cc int3 25: cc int3 26: 48 8b 0c 24 mov (%rsp),%rcx * 2a: 89 f6 mov %esi,%esi <-- trapping instruction 2c: 31 d2 xor %edx,%edx 2e: e9 f3 f9 ff ff jmpq 0xfffffa26 33: 0f 1f 00 nopl (%rax) 36: 48 8b 0c 24 mov (%rsp),%rcx 3a: 89 f6 mov %esi,%esi 3c: ba .byte 0xba 3d: 01 00 add %eax,(%rax)