INFO: task syz-executor.3:25194 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.3 state:D stack:28296 pid:25194 ppid: 6745 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 del_gendisk+0x598/0x860 block/genhd.c:623 loop_remove+0x39/0xf0 drivers/block/loop.c:2080 loop_control_remove drivers/block/loop.c:2137 [inline] loop_control_ioctl+0x445/0x4a0 drivers/block/loop.c:2175 __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: 0023:0xf6f38549 RSP: 002b:00000000f45115fc EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000004c81 RDX: 0000000000000000 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/6236: #0: ffff888071c10870 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 ============================================= 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: 2961 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:unwind_next_frame+0xd26/0x1ce0 arch/x86/kernel/unwind_orc.c:540 Code: 08 4c 8b 64 24 60 48 c1 ea 03 80 3c 02 00 0f 85 86 0e 00 00 48 8b 14 24 4d 89 66 38 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 44 0e 00 00 49 8d 7e 58 49 c7 46 50 00 00 00 00 RSP: 0018:ffffc90001f5f870 EFLAGS: 00000a06 RAX: dffffc0000000000 RBX: 1ffff920003ebf16 RCX: ffffffff8e18266f RDX: 1ffff920003ebf33 RSI: ffffc90001f5fc80 RDI: ffffc90001f5fc80 RBP: 0000000000000001 R08: ffffffff8e18266a R09: 0000000000000001 R10: fffff520003ebf34 R11: 000000000008808a R12: ffffc90001f5fc88 R13: ffffc90001f5f97d R14: ffffc90001f5f948 R15: ffffffff8e18266e FS: 00007f1f40bed8c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1f3e173000 CR3: 0000000022df9000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:46 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free mm/kasan/common.c:328 [inline] __kasan_slab_free+0xff/0x130 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:1723 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1749 slab_free mm/slub.c:3513 [inline] kmem_cache_free+0x92/0x5e0 mm/slub.c:3529 putname fs/namei.c:270 [inline] putname+0xfe/0x140 fs/namei.c:256 do_sys_openat2+0x153/0x4d0 fs/open.c:1221 do_sys_open fs/open.c:1228 [inline] __do_sys_open fs/open.c:1236 [inline] __se_sys_open fs/open.c:1232 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1232 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: 0033:0x7f1f4017c840 Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24 RSP: 002b:00007ffe170797d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007ffe17079ae0 RCX: 00007f1f4017c840 RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 00005567d915cf30 RBP: 000000000000000d R08: 000000000000c0ff R09: 00000000ffffffff R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff R13: 00005567d9150040 R14: 00007ffe17079aa0 R15: 00005567d915d920 ---------------- Code disassembly (best guess): 0: 08 4c 8b 64 or %cl,0x64(%rbx,%rcx,4) 4: 24 60 and $0x60,%al 6: 48 c1 ea 03 shr $0x3,%rdx a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) e: 0f 85 86 0e 00 00 jne 0xe9a 14: 48 8b 14 24 mov (%rsp),%rdx 18: 4d 89 66 38 mov %r12,0x38(%r14) 1c: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 23: fc ff df 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 0f 85 44 0e 00 00 jne 0xe78 34: 49 8d 7e 58 lea 0x58(%r14),%rdi 38: 49 c7 46 50 00 00 00 movq $0x0,0x50(%r14) 3f: 00