INFO: task syz-executor.4:12257 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.4 state:D stack:27680 pid:12257 ppid: 9400 flags:0x00004004 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 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: 0033:0x7fcc4a5dcae9 RSP: 002b:00007fcc47b31188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fcc4a6f0020 RCX: 00007fcc4a5dcae9 RDX: 0000000000000000 RSI: 0000000000004c81 RDI: 0000000000000005 RBP: 00007fcc4a636f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff433868df R14: 00007fcc47b31300 R15: 0000000000022000 Showing all locks held in the system: 3 locks held by kworker/u4:0/8: #0: ffff8880b9d39a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:478 #1: ffff8880b9d279c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x3a6/0x490 kernel/sched/psi.c:880 #2: ffff88801da78d40 (&wdev->mtx){+.+.}-{3:3}, at: sdata_lock net/mac80211/ieee80211_i.h:1013 [inline] #2: ffff88801da78d40 (&wdev->mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0x90/0xe80 net/mac80211/ibss.c:1681 1 lock held by khungtaskd/27: #0: ffffffff8bb83ae0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 3 locks held by kworker/u4:3/90: #0: ffff8880b9d39a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:478 #1: ffff888011fee098 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xab/0x15a0 kernel/sched/core.c:4003 #2: ffffffff8bb83ae0 (rcu_read_lock){....}-{1:2}, at: batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:410 [inline] #2: ffffffff8bb83ae0 (rcu_read_lock){....}-{1:2}, at: batadv_nc_worker+0xf3/0xfa0 net/batman-adv/network-coding.c:723 1 lock held by in:imklog/6212: #0: ffff8880735de870 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 ============================================= NMI backtrace for cpu 0 CPU: 0 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 45 Comm: kworker/u4:2 Not tainted 5.16.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_mcast_mla_update RIP: 0010:check_region_inline mm/kasan/generic.c:170 [inline] RIP: 0010:kasan_check_range+0x12c/0x180 mm/kasan/generic.c:189 Code: 00 74 ef 49 8d 04 2c 48 85 d2 75 0b 48 89 da 48 29 c2 e9 55 ff ff ff 49 39 d2 75 17 49 0f be 02 41 83 e1 07 49 39 c1 7d 0a 5b 01 00 00 00 5d 41 5c c3 44 89 c2 e8 53 ef ff ff 5b 83 f0 01 5d RSP: 0018:ffffc9000114fc18 EFLAGS: 00000246 RAX: fffffbfff1b22e6b RBX: 1ffff92000229f88 RCX: ffffffff815d0368 RDX: fffffbfff1b22e6b RSI: 0000000000000008 RDI: ffffffff8d917350 RBP: fffffbfff1b22e6a R08: 0000000000000000 R09: ffffffff8d917357 R10: fffffbfff1b22e6a R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffc9000114fdb0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f798e7a9000 CR3: 0000000018f3c000 CR4: 0000000000350ee0 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] cpumask_test_cpu include/linux/cpumask.h:344 [inline] cpu_online include/linux/cpumask.h:895 [inline] trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0xb8/0x510 kernel/locking/lockdep.c:5608 process_one_work+0x921/0x1690 kernel/workqueue.c:2274 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 00 74 ef 49 add %dh,0x49(%rdi,%rbp,8) 4: 8d 04 2c lea (%rsp,%rbp,1),%eax 7: 48 85 d2 test %rdx,%rdx a: 75 0b jne 0x17 c: 48 89 da mov %rbx,%rdx f: 48 29 c2 sub %rax,%rdx 12: e9 55 ff ff ff jmpq 0xffffff6c 17: 49 39 d2 cmp %rdx,%r10 1a: 75 17 jne 0x33 1c: 49 0f be 02 movsbq (%r10),%rax 20: 41 83 e1 07 and $0x7,%r9d 24: 49 39 c1 cmp %rax,%r9 27: 7d 0a jge 0x33 29: 5b pop %rbx * 2a: b8 01 00 00 00 mov $0x1,%eax <-- trapping instruction 2f: 5d pop %rbp 30: 41 5c pop %r12 32: c3 retq 33: 44 89 c2 mov %r8d,%edx 36: e8 53 ef ff ff callq 0xffffef8e 3b: 5b pop %rbx 3c: 83 f0 01 xor $0x1,%eax 3f: 5d pop %rbp