INFO: task systemd-udevd:16051 blocked for more than 143 seconds. Not tainted 5.14.0-rc5-next-20210813-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:systemd-udevd state:D stack:28368 pid:16051 ppid: 2984 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4711 [inline] __schedule+0x93a/0x26f0 kernel/sched/core.c:5966 schedule+0xd3/0x270 kernel/sched/core.c:6045 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6104 __mutex_lock_common kernel/locking/mutex.c:1036 [inline] __mutex_lock+0xa46/0x1300 kernel/locking/mutex.c:1096 del_gendisk+0x84/0x6f0 block/genhd.c:597 nbd_dev_remove drivers/block/nbd.c:241 [inline] nbd_put.part.0+0x82/0x160 drivers/block/nbd.c:263 nbd_put drivers/block/nbd.c:1527 [inline] nbd_release+0x14d/0x1a0 drivers/block/nbd.c:1526 blkdev_put_whole fs/block_dev.c:1096 [inline] blkdev_put+0x2fb/0x9e0 fs/block_dev.c:1387 blkdev_close+0x8c/0xb0 fs/block_dev.c:1397 __fput+0x288/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fbfd0765270 RSP: 002b:00007ffcb2fbb9a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007fbfd0765270 RDX: 000000000aba9500 RSI: 0000000000000000 RDI: 0000000000000007 RBP: 00007fbfd161f710 R08: 0000000000000045 R09: 0000000000000018 R10: 0000561f78676798 R11: 0000000000000246 R12: 0000000000000000 R13: 0000561f78676330 R14: 0000000000000003 R15: 000000000000000e INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 PID: 26 Comm: khungtaskd Not tainted 5.14.0-rc5-next-20210813-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:254 [inline] watchdog+0xcb7/0xed0 kernel/hung_task.c:339 kthread+0x3e5/0x4d0 kernel/kthread.c:319 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: 8977 Comm: kworker/u4:7 Not tainted 5.14.0-rc5-next-20210813-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: phy6 ieee80211_iface_work RIP: 0010:__sanitizer_cov_trace_cmp8+0xc/0x70 kernel/kcov.c:263 Code: e8 48 c7 44 38 e0 07 00 00 00 48 89 4c 38 f0 4e 89 54 c8 20 48 89 10 c3 66 0f 1f 44 00 00 49 89 f8 bf 03 00 00 00 4c 8b 14 24 <48> 89 f1 65 48 8b 34 25 40 f0 01 00 e8 c3 f1 ff ff 84 c0 74 48 48 RSP: 0018:ffffc900057df3d8 EFLAGS: 00000086 RAX: 00000000ffffffaa RBX: ffffffff9028a8c8 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff88823bd31000 RDI: 0000000000000003 RBP: ffff88823bd31000 R08: ffff88823bd30241 R09: ffffffff8eee504f R10: ffffffff81bbb9f0 R11: 0000000000000001 R12: ffff888010c41640 R13: 0000000000000028 R14: ffff88823bd30241 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007faefadb9000 CR3: 000000000b68e000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: for_each_canary mm/kfence/core.c:254 [inline] kfence_guarded_alloc mm/kfence/core.c:321 [inline] __kfence_alloc+0x710/0xca0 mm/kfence/core.c:779 kfence_alloc include/linux/kfence.h:123 [inline] slab_alloc_node mm/slub.c:3091 [inline] slab_alloc mm/slub.c:3181 [inline] __kmalloc+0x220/0x320 mm/slub.c:4354 kmalloc include/linux/slab.h:596 [inline] ieee802_11_parse_elems_crc+0x121/0xfe0 net/mac80211/util.c:1465 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2186 [inline] ieee80211_rx_mgmt_probe_beacon+0x17f/0x17c0 net/mac80211/ibss.c:1612 ieee80211_ibss_rx_queued_mgmt+0xd30/0x1610 net/mac80211/ibss.c:1642 ieee80211_iface_process_skb net/mac80211/iface.c:1426 [inline] ieee80211_iface_work+0x7f7/0xa40 net/mac80211/iface.c:1462 process_one_work+0x98d/0x1630 kernel/workqueue.c:2275 worker_thread+0x658/0x11f0 kernel/workqueue.c:2421 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: e8 48 c7 44 38 callq 0x3844c74d 5: e0 07 loopne 0xe 7: 00 00 add %al,(%rax) 9: 00 48 89 add %cl,-0x77(%rax) c: 4c 38 f0 rex.WR cmp %r14b,%al f: 4e 89 54 c8 20 mov %r10,0x20(%rax,%r9,8) 14: 48 89 10 mov %rdx,(%rax) 17: c3 retq 18: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) 1e: 49 89 f8 mov %rdi,%r8 21: bf 03 00 00 00 mov $0x3,%edi 26: 4c 8b 14 24 mov (%rsp),%r10 2a: 48 89 f1 mov %rsi,%rcx <-- trapping instruction 2d: 65 48 8b 34 25 40 f0 mov %gs:0x1f040,%rsi 34: 01 00 36: e8 c3 f1 ff ff callq 0xfffff1fe 3b: 84 c0 test %al,%al 3d: 74 48 je 0x87 3f: 48 rex.W