INFO: task syz-executor.0:9873 blocked for more than 143 seconds. Not tainted 5.16.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:27496 pid: 9873 ppid: 6546 flags:0x20004004 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6253 schedule+0xd2/0x260 kernel/sched/core.c:6326 blk_mq_freeze_queue_wait+0x112/0x160 block/blk-mq.c:178 loop_set_status+0x440/0x930 drivers/block/loop.c:1264 loop_set_status_compat+0xac/0x100 drivers/block/loop.c:1674 lo_compat_ioctl+0xeb/0x110 drivers/block/loop.c:1700 compat_blkdev_ioctl+0x3b8/0x810 block/ioctl.c:674 __do_compat_sys_ioctl+0x1c7/0x290 fs/ioctl.c:972 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf6f37549 RSP: 002b:00000000f45105fc EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000004c02 RDX: 00000000200000c0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8bb83a60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 1 lock held by in:imklog/6433: #0: ffff88801dcc74f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 1 lock held by syz-executor.0/9873: #0: ffff88801a57eb60 (&lo->lo_mutex){+.+.}-{3:3}, at: loop_set_status+0x2a/0x930 drivers/block/loop.c:1248 2 locks held by systemd-udevd/9872: #0: ffff88801a62b118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0x9b/0xb50 block/bdev.c:819 #1: ffff88801a57eb60 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_open+0x75/0x120 drivers/block/loop.c:1733 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.16.0-rc1-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: 2965 Comm: systemd-journal Not tainted 5.16.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rcu_is_watching+0x75/0xb0 kernel/rcu/tree.c:1122 Code: ff df 48 89 da 48 c1 ea 03 0f b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 19 8b 03 83 e0 01 65 ff 0d 5b 23 9f 7e <74> 03 5b 5d c3 e8 90 f8 9c ff 5b 5d c3 48 89 df e8 e6 52 5b 00 eb RSP: 0018:ffffc90001f6fd50 EFLAGS: 00000282 RAX: 0000000000000001 RBX: ffff8880b9c3aa50 RCX: ffffffff815d0368 RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffffffff8b5648a0 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8d9172d7 R10: fffffbfff1b22e5a R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: ffffffff8bca8120 R15: 0000000000000000 FS: 00007f2c9b97a8c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2c98daf000 CR3: 000000001bf59000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:108 [inline] rcu_read_lock_sched_held+0x1c/0x70 kernel/rcu/update.c:123 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0x442/0x510 kernel/locking/lockdep.c:5608 __fs_reclaim_acquire mm/page_alloc.c:4535 [inline] fs_reclaim_acquire+0x115/0x160 mm/page_alloc.c:4549 might_alloc include/linux/sched/mm.h:227 [inline] slab_pre_alloc_hook mm/slab.h:492 [inline] slab_alloc_node mm/slub.c:3148 [inline] slab_alloc mm/slub.c:3242 [inline] kmem_cache_alloc+0x3e/0x3a0 mm/slub.c:3247 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138 getname_flags include/linux/audit.h:323 [inline] getname fs/namei.c:217 [inline] __do_sys_mkdir fs/namei.c:3929 [inline] __se_sys_mkdir fs/namei.c:3927 [inline] __x64_sys_mkdir+0xda/0x140 fs/namei.c:3927 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: 0033:0x7f2c9ac35687 Code: 00 b8 ff ff ff ff c3 0f 1f 40 00 48 8b 05 09 d8 2b 00 64 c7 00 5f 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 b8 53 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 d7 2b 00 f7 d8 64 89 01 48 RSP: 002b:00007ffcee372b28 EFLAGS: 00000293 ORIG_RAX: 0000000000000053 RAX: ffffffffffffffda RBX: 00007ffcee375a40 RCX: 00007f2c9ac35687 RDX: 00007f2c9b6a6a00 RSI: 00000000000001ed RDI: 00005626e85d58a0 RBP: 00007ffcee372b60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000069 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffcee375a40 R15: 00007ffcee373050 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 48 89 da mov %rbx,%rdx 3: 48 c1 ea 03 shr $0x3,%rdx 7: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx b: 48 89 d8 mov %rbx,%rax e: 83 e0 07 and $0x7,%eax 11: 83 c0 03 add $0x3,%eax 14: 38 d0 cmp %dl,%al 16: 7c 04 jl 0x1c 18: 84 d2 test %dl,%dl 1a: 75 19 jne 0x35 1c: 8b 03 mov (%rbx),%eax 1e: 83 e0 01 and $0x1,%eax 21: 65 ff 0d 5b 23 9f 7e decl %gs:0x7e9f235b(%rip) # 0x7e9f2383 * 28: 74 03 je 0x2d <-- trapping instruction 2a: 5b pop %rbx 2b: 5d pop %rbp 2c: c3 retq 2d: e8 90 f8 9c ff callq 0xff9cf8c2 32: 5b pop %rbx 33: 5d pop %rbp 34: c3 retq 35: 48 89 df mov %rbx,%rdi 38: e8 e6 52 5b 00 callq 0x5b5323 3d: eb .byte 0xeb