sr 1:0:0:0: [sr0] tag#0 unaligned transfer
I/O error, dev sr0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 2 prio class 0
Please do not flush events_freezable_power_ WQ.
======================================================
WARNING: possible circular locking dependency detected
5.17.0-rc5-next-20220222 #1 Not tainted
------------------------------------------------------
syz-executor.4/18846 is trying to acquire lock:
ffffffff851162a0 (console_owner){-.-.}-{0:0}, at: console_unlock+0x34e/0xd40 kernel/printk/printk.c:2771

but task is already holding lock:
ffff88806ce37418 (&pool->lock){-.-.}-{2:2}, at: start_flush_work kernel/workqueue.c:3036 [inline]
ffff88806ce37418 (&pool->lock){-.-.}-{2:2}, at: __flush_work+0x17f/0xae0 kernel/workqueue.c:3091

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&pool->lock){-.-.}-{2:2}:
       __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
       _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
       __queue_work+0x39f/0x10a0 kernel/workqueue.c:1474
       queue_work_on+0xae/0xc0 kernel/workqueue.c:1545
       queue_work include/linux/workqueue.h:514 [inline]
       schedule_work include/linux/workqueue.h:575 [inline]
       p9_pollwake+0xb9/0x170 net/9p/trans_fd.c:534
       __wake_up_common+0x14c/0x4c0 kernel/sched/wait.c:108
       __wake_up_common_lock+0xd0/0x130 kernel/sched/wait.c:138
       tty_write_unlock drivers/tty/tty_io.c:945 [inline]
       do_tty_write drivers/tty/tty_io.c:1049 [inline]
       file_tty_write.constprop.0+0x62f/0x910 drivers/tty/tty_io.c:1095
       __kernel_write+0x59e/0xb40 fs/read_write.c:536
       kernel_write fs/read_write.c:565 [inline]
       kernel_write+0xe2/0x550 fs/read_write.c:555
       p9_fd_write net/9p/trans_fd.c:428 [inline]
       p9_write_work+0x25a/0xc30 net/9p/trans_fd.c:479
       process_one_work+0xa1c/0x16a0 kernel/workqueue.c:2289
       worker_thread+0x637/0x1250 kernel/workqueue.c:2436
       kthread+0x2f0/0x3a0 kernel/kthread.c:376
       ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:295

-> #2 (&tty->write_wait){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162
       __wake_up_common_lock+0xb4/0x130 kernel/sched/wait.c:137
       tty_port_default_wakeup+0x26/0x40 drivers/tty/tty_port.c:51
       serial8250_tx_chars+0x50b/0xb00 drivers/tty/serial/8250/8250_port.c:1853
       serial8250_handle_irq.part.0+0x3f1/0x4c0 drivers/tty/serial/8250/8250_port.c:1940
       serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1913 [inline]
       serial8250_default_handle_irq+0xb8/0x230 drivers/tty/serial/8250/8250_port.c:1957
       serial8250_interrupt+0xf4/0x1a0 drivers/tty/serial/8250/8250_core.c:126
       __handle_irq_event_percpu+0x20f/0x820 kernel/irq/handle.c:158
       handle_irq_event_percpu kernel/irq/handle.c:193 [inline]
       handle_irq_event+0xa7/0x1e0 kernel/irq/handle.c:210
       handle_edge_irq+0x262/0xd10 kernel/irq/chip.c:817
       generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
       handle_irq arch/x86/kernel/irq.c:231 [inline]
       __common_interrupt+0x92/0x1d0 arch/x86/kernel/irq.c:250
       common_interrupt+0x9f/0xc0 arch/x86/kernel/irq.c:240
       asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629
       native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
       arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
       default_idle+0xb/0x10 arch/x86/kernel/process.c:733
       default_idle_call+0x87/0xd0 kernel/sched/idle.c:112
       cpuidle_idle_call kernel/sched/idle.c:194 [inline]
       do_idle+0x3b9/0x530 kernel/sched/idle.c:306
       cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
       secondary_startup_64_no_verify+0xd5/0xdb

-> #1 (&port_lock_key){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162
       serial8250_console_write+0x90e/0xb20 drivers/tty/serial/8250/8250_port.c:3359
       call_console_drivers kernel/printk/printk.c:1953 [inline]
       console_unlock+0x8c7/0xd40 kernel/printk/printk.c:2775
       register_console kernel/printk/printk.c:3122 [inline]
       register_console+0x378/0x7d0 kernel/printk/printk.c:3013
       univ8250_console_init+0x3a/0x46 drivers/tty/serial/8250/8250_core.c:679
       console_init+0x3c1/0x58d kernel/printk/printk.c:3232
       start_kernel+0x301/0x4aa init/main.c:1068
       secondary_startup_64_no_verify+0xd5/0xdb

-> #0 (console_owner){-.-.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3096 [inline]
       check_prevs_add kernel/locking/lockdep.c:3219 [inline]
       validate_chain kernel/locking/lockdep.c:3834 [inline]
       __lock_acquire+0x2c2f/0x6120 kernel/locking/lockdep.c:5060
       lock_acquire kernel/locking/lockdep.c:5672 [inline]
       lock_acquire+0x1a2/0x4d0 kernel/locking/lockdep.c:5637
       console_lock_spinning_enable kernel/printk/printk.c:1795 [inline]
       console_unlock+0x3a1/0xd40 kernel/printk/printk.c:2772
       vprintk_emit+0x1b4/0x550 kernel/printk/printk.c:2273
       vprintk+0x80/0x90 kernel/printk/printk_safe.c:50
       _printk+0xba/0xed kernel/printk/printk.c:2294
       warn_flush_attempt kernel/workqueue.c:2613 [inline]
       check_flush_dependency.cold+0x18/0x4e kernel/workqueue.c:2635
       start_flush_work kernel/workqueue.c:3049 [inline]
       __flush_work+0x246/0xae0 kernel/workqueue.c:3091
       __cancel_work_timer+0x398/0x4d0 kernel/workqueue.c:3179
       disk_block_events+0x102/0x130 block/disk-events.c:93
       blkdev_get_by_dev+0xe4/0xcb0 block/bdev.c:805
       blkdev_open+0x154/0x2e0 block/fops.c:498
       do_dentry_open+0x4b7/0x1110 fs/open.c:957
       do_open fs/namei.c:3476 [inline]
       path_openat+0x1a3e/0x28a0 fs/namei.c:3609
       do_filp_open+0x1aa/0x400 fs/namei.c:3636
       do_sys_openat2+0x16d/0x4d0 fs/open.c:1347
       do_sys_open fs/open.c:1363 [inline]
       __do_sys_openat fs/open.c:1379 [inline]
       __se_sys_openat fs/open.c:1374 [inline]
       __x64_sys_openat+0x13f/0x1f0 fs/open.c:1374
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x44/0xae

other info that might help us debug this:

Chain exists of:
  console_owner --> &tty->write_wait --> &pool->lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&pool->lock);
                               lock(&tty->write_wait);
                               lock(&pool->lock);
  lock(console_owner);

 *** DEADLOCK ***

4 locks held by syz-executor.4/18846:
 #0: ffff88800ef9dcc0 (&ev->block_mutex){+.+.}-{3:3}, at: disk_block_events+0x5b/0x130 block/disk-events.c:86
 #1: ffffffff85202f00 (rcu_read_lock){....}-{1:2}, at: __flush_work+0xf9/0xae0 kernel/workqueue.c:3086
 #2: ffff88806ce37418 (&pool->lock){-.-.}-{2:2}, at: start_flush_work kernel/workqueue.c:3036 [inline]
 #2: ffff88806ce37418 (&pool->lock){-.-.}-{2:2}, at: __flush_work+0x17f/0xae0 kernel/workqueue.c:3091
 #3: ffffffff851f66e0 (console_lock){+.+.}-{0:0}, at: vprintk+0x80/0x90 kernel/printk/printk_safe.c:50

stack backtrace:
CPU: 1 PID: 18846 Comm: syz-executor.4 Not tainted 5.17.0-rc5-next-20220222 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x8b/0xb3 lib/dump_stack.c:106
 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2176
 check_prev_add kernel/locking/lockdep.c:3096 [inline]
 check_prevs_add kernel/locking/lockdep.c:3219 [inline]
 validate_chain kernel/locking/lockdep.c:3834 [inline]
 __lock_acquire+0x2c2f/0x6120 kernel/locking/lockdep.c:5060
 lock_acquire kernel/locking/lockdep.c:5672 [inline]
 lock_acquire+0x1a2/0x4d0 kernel/locking/lockdep.c:5637
 console_lock_spinning_enable kernel/printk/printk.c:1795 [inline]
 console_unlock+0x3a1/0xd40 kernel/printk/printk.c:2772
 vprintk_emit+0x1b4/0x550 kernel/printk/printk.c:2273
 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50
 _printk+0xba/0xed kernel/printk/printk.c:2294
 warn_flush_attempt kernel/workqueue.c:2613 [inline]
 check_flush_dependency.cold+0x18/0x4e kernel/workqueue.c:2635
 start_flush_work kernel/workqueue.c:3049 [inline]
 __flush_work+0x246/0xae0 kernel/workqueue.c:3091
 __cancel_work_timer+0x398/0x4d0 kernel/workqueue.c:3179
 disk_block_events+0x102/0x130 block/disk-events.c:93
 blkdev_get_by_dev+0xe4/0xcb0 block/bdev.c:805
 blkdev_open+0x154/0x2e0 block/fops.c:498
 do_dentry_open+0x4b7/0x1110 fs/open.c:957
 do_open fs/namei.c:3476 [inline]
 path_openat+0x1a3e/0x28a0 fs/namei.c:3609
 do_filp_open+0x1aa/0x400 fs/namei.c:3636
 do_sys_openat2+0x16d/0x4d0 fs/open.c:1347
 do_sys_open fs/open.c:1363 [inline]
 __do_sys_openat fs/open.c:1379 [inline]
 __se_sys_openat fs/open.c:1374 [inline]
 __x64_sys_openat+0x13f/0x1f0 fs/open.c:1374
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fe050fa9b19
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe04e51f188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fe0510bcf60 RCX: 00007fe050fa9b19
RDX: 0000000000040b01 RSI: 0000000020000000 RDI: ffffffffffffff9c
RBP: 00007fe051003f6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff2b8f9f8f R14: 00007fe04e51f300 R15: 0000000000022000
 </TASK>
CPU: 1 PID: 18846 Comm: syz-executor.4 Not tainted 5.17.0-rc5-next-20220222 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x8b/0xb3 lib/dump_stack.c:106
 warn_flush_attempt kernel/workqueue.c:2614 [inline]
 check_flush_dependency.cold+0x1d/0x4e kernel/workqueue.c:2635
 start_flush_work kernel/workqueue.c:3049 [inline]
 __flush_work+0x246/0xae0 kernel/workqueue.c:3091
 __cancel_work_timer+0x398/0x4d0 kernel/workqueue.c:3179
 disk_block_events+0x102/0x130 block/disk-events.c:93
 blkdev_get_by_dev+0xe4/0xcb0 block/bdev.c:805
 blkdev_open+0x154/0x2e0 block/fops.c:498
 do_dentry_open+0x4b7/0x1110 fs/open.c:957
 do_open fs/namei.c:3476 [inline]
 path_openat+0x1a3e/0x28a0 fs/namei.c:3609
 do_filp_open+0x1aa/0x400 fs/namei.c:3636
 do_sys_openat2+0x16d/0x4d0 fs/open.c:1347
 do_sys_open fs/open.c:1363 [inline]
 __do_sys_openat fs/open.c:1379 [inline]
 __se_sys_openat fs/open.c:1374 [inline]
 __x64_sys_openat+0x13f/0x1f0 fs/open.c:1374
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fe050fa9b19
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe04e51f188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fe0510bcf60 RCX: 00007fe050fa9b19
RDX: 0000000000040b01 RSI: 0000000020000000 RDI: ffffffffffffff9c
RBP: 00007fe051003f6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff2b8f9f8f R14: 00007fe04e51f300 R15: 0000000000022000
 </TASK>