INFO: task syz-executor.2:10077 can't die for more than 143 seconds.
task:syz-executor.2  state:D stack:28352 pid:10077 ppid:  8442 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:4324 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5075
 schedule+0xcf/0x270 kernel/sched/core.c:5154
 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1868
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x168/0x270 kernel/sched/completion.c:138
 io_sq_thread_finish+0x96/0x580 fs/io_uring.c:7152
 io_sq_offload_create fs/io_uring.c:7929 [inline]
 io_uring_create fs/io_uring.c:9465 [inline]
 io_uring_setup+0x1fb2/0x2c20 fs/io_uring.c:9550
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x465ef9
RSP: 002b:00007f74524fb188 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465ef9
RDX: 0000000000000000 RSI: 0000000020000100 RDI: 00000000000022c3
RBP: 00000000004bcd1c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007fffc714866f R14: 00007f74524fb300 R15: 0000000000022000
INFO: task syz-executor.2:10077 blocked for more than 143 seconds.
      Not tainted 5.11.0-next-20210225-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:28352 pid:10077 ppid:  8442 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:4324 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5075
 schedule+0xcf/0x270 kernel/sched/core.c:5154
 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1868
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x168/0x270 kernel/sched/completion.c:138
 io_sq_thread_finish+0x96/0x580 fs/io_uring.c:7152
 io_sq_offload_create fs/io_uring.c:7929 [inline]
 io_uring_create fs/io_uring.c:9465 [inline]
 io_uring_setup+0x1fb2/0x2c20 fs/io_uring.c:9550
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x465ef9
RSP: 002b:00007f74524fb188 EFLAGS: 00000246 ORIG_RAX: 00000000000001a9
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465ef9
RDX: 0000000000000000 RSI: 0000000020000100 RDI: 00000000000022c3
RBP: 00000000004bcd1c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007fffc714866f R14: 00007f74524fb300 R15: 0000000000022000
INFO: task iou-sqp-10077:10092 can't die for more than 143 seconds.
task:iou-sqp-10077   state:D stack:30296 pid:10092 ppid:  8442 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:4324 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5075
 schedule+0xcf/0x270 kernel/sched/core.c:5154
 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1868
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x168/0x270 kernel/sched/completion.c:138
 io_sq_thread+0x27d/0x19a0 fs/io_uring.c:6731
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
INFO: task iou-sqp-10077:10092 blocked for more than 143 seconds.
      Not tainted 5.11.0-next-20210225-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:iou-sqp-10077   state:D stack:30296 pid:10092 ppid:  8442 flags:0x00004004
Call Trace:
 context_switch kernel/sched/core.c:4324 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5075
 schedule+0xcf/0x270 kernel/sched/core.c:5154
 schedule_timeout+0x1db/0x250 kernel/time/timer.c:1868
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x168/0x270 kernel/sched/completion.c:138
 io_sq_thread+0x27d/0x19a0 fs/io_uring.c:6731
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Showing all locks held in the system:
1 lock held by khungtaskd/1668:
 #0: ffffffff8bf744e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6327
1 lock held by in:imklog/8123:
 #0: ffff888013c6c0f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:961

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 1668 Comm: khungtaskd Not tainted 5.11.0-next-20210225-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0xfa/0x151 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline]
 watchdog+0xd8e/0xf40 kernel/hung_task.c:338
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 8548 Comm: kworker/u4:0 Not tainted 5.11.0-next-20210225-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: phy8 ieee80211_iface_work
RIP: 0010:compound_head include/linux/page-flags.h:187 [inline]
RIP: 0010:virt_to_head_page include/linux/mm.h:880 [inline]
RIP: 0010:kmem_cache_free+0x77/0x730 mm/slub.c:3177
Code: c1 e8 0c 4c 89 6c 24 30 48 c7 44 24 38 00 00 00 00 49 89 c4 48 b8 00 00 00 00 00 ea ff ff 49 c1 e4 06 49 01 c4 49 8b 44 24 08 <48> 8d 50 ff a8 01 4c 0f 45 e2 48 8d 54 24 38 e8 35 86 ff ff 84 c0
RSP: 0018:ffffc90002197bf8 EFLAGS: 00000282
RAX: dead000000000100 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88801be11c00 RSI: ffffc90002197c28 RDI: ffff8881406fbc80
RBP: ffff8881406fbc80 R08: 0000000000000000 R09: 000000000000002e
R10: ffffffff813332fa R11: 000000000000003f R12: ffffea0000516540
R13: ffff888014595140 R14: dffffc0000000000 R15: 0000000000000080
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007feea6f41278 CR3: 0000000011a8a000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:683
 __kfree_skb net/core/skbuff.c:740 [inline]
 kfree_skb net/core/skbuff.c:757 [inline]
 kfree_skb+0x140/0x3f0 net/core/skbuff.c:751
 ieee80211_iface_work+0x2cf/0x9e0 net/mac80211/iface.c:1451
 process_one_work+0x98d/0x1600 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294