INFO: task syz.7.3121:10034 blocked for more than 122 seconds.
      Not tainted 6.12.30-syzkaller-g153a0a38e976 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.3121      state:D stack:0     pid:10034 tgid:10033 ppid:6831   flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5924 [inline]
 __schedule+0x145b/0x1f10 kernel/sched/core.c:7750
 __schedule_loop kernel/sched/core.c:7831 [inline]
 schedule+0xc6/0x240 kernel/sched/core.c:7846
 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7903
 __mutex_lock_common kernel/locking/mutex.c:692 [inline]
 __mutex_lock+0x836/0x1b60 kernel/locking/mutex.c:786
 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1117
 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:270
 device_lock include/linux/device.h:1025 [inline]
 usbdev_open+0x171/0x840 drivers/usb/core/devio.c:1051
 chrdev_open+0x4de/0x5f0 fs/char_dev.c:414
 do_dentry_open+0x97b/0x1510 fs/open.c:960
 vfs_open+0x86/0x230 fs/open.c:1090
 do_open fs/namei.c:3774 [inline]
 path_openat+0x2b6c/0x34b0 fs/namei.c:3933
 do_filp_open+0x1c6/0x3e0 fs/namei.c:3960
 do_sys_openat2+0x12c/0x1c0 fs/open.c:1438
 do_sys_open fs/open.c:1453 [inline]
 __do_sys_openat fs/open.c:1469 [inline]
 __se_sys_openat fs/open.c:1464 [inline]
 __x64_sys_openat+0x13a/0x170 fs/open.c:1464
 x64_sys_call+0xe69/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fa2d6d8d290
RSP: 002b:00007fa2d7c1bb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000082 RCX: 00007fa2d6d8d290
RDX: 0000000000000082 RSI: 00007fa2d7c1bc10 RDI: 00000000ffffff9c
RBP: 00007fa2d7c1bc10 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd
R13: 0000000000000000 R14: 00007fa2d6fb5fa0 R15: 00007ffe6120f4b8
 </TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted 6.12.30-syzkaller-g153a0a38e976 #0 148e3123b04ac6bd10e65cc50fbc76805c129a8d
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:94
 dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
 dump_stack+0x19/0x20 lib/dump_stack.c:129
 nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:229 [inline]
 watchdog+0xd8f/0xed0 kernel/hung_task.c:385
 kthread+0x2ca/0x370 kernel/kthread.c:389
 ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 15199 Comm: syz.2.4794 Not tainted 6.12.30-syzkaller-g153a0a38e976 #0 148e3123b04ac6bd10e65cc50fbc76805c129a8d
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:folio_test_swapcache include/linux/page-flags.h:589 [inline]
RIP: 0010:folio_mapping+0x9c/0x1b0 mm/util.c:866
Code: 3c 3e 00 74 08 48 89 df e8 d1 be 15 00 4c 8b 23 4c 89 e6 48 81 e6 00 00 04 00 31 ff e8 7d cb bf ff 49 81 e4 00 00 04 00 75 07 <e8> 8f c6 bf ff eb 3e 48 89 df be 08 00 00 00 e8 70 c1 15 00 43 80
RSP: 0018:ffffc900083fe6d0 EFLAGS: 00000246
RAX: ffffffff81c5db43 RBX: ffffea00051ed640 RCX: ffff88811ddd3900
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900083fe6f0 R08: ffffea00051ed647 R09: 1ffffd4000a3dac8
R10: dffffc0000000000 R11: fffff94000a3dac9 R12: 0000000000000000
R13: dffffc0000000000 R14: 1ffffd4000a3dac8 R15: dffffc0000000000
FS:  00007f8d144d06c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8d144aef98 CR3: 0000000119e00000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 __folio_end_writeback+0xea/0x6c0 mm/page-writeback.c:3080
 folio_end_writeback+0xf1/0x300 mm/filemap.c:1661
 end_buffer_async_write+0x220/0x2f0 fs/buffer.c:409
 end_bio_bh_io_sync+0xda/0x150 fs/buffer.c:2771
 bio_endio+0x6f5/0x7f0 block/bio.c:1551
 blk_update_request+0x569/0xf10 block/blk-mq.c:1015
 blk_mq_end_request+0x45/0x80 block/blk-mq.c:1143
 <kernel::block::mq::request::Request<rnull::NullBlkDevice>>::end_ok rust/kernel/block/mq/request.rs:128 [inline]
 <rnull::NullBlkDevice as kernel::block::mq::operations::Operations>::queue_rq drivers/block/rnull.rs:62 [inline]
 <kernel::block::mq::operations::OperationsVTable<rnull::NullBlkDevice>>::queue_rq_callback+0x1b6/0x2a0 rust/kernel/block/mq/operations.rs:93
 blk_mq_dispatch_rq_list+0xa8b/0x1b00 block/blk-mq.c:2131
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline]
 blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline]
 __blk_mq_sched_dispatch_requests+0xdfc/0x1610 block/blk-mq-sched.c:309
 blk_mq_sched_dispatch_requests+0xe5/0x1c0 block/blk-mq-sched.c:331
 blk_mq_run_hw_queue+0x1c8/0x2a0 block/blk-mq.c:2373
 blk_mq_dispatch_plug_list include/linux/spinlock.h:-1 [inline]
 blk_mq_flush_plug_list+0xcf3/0x1730 block/blk-mq.c:2935
 __blk_flush_plug+0x3e2/0x4c0 block/blk-core.c:1253
 blk_finish_plug+0x62/0x90 block/blk-core.c:1280
 blkdev_writepages+0xb4/0x100 block/fops.c:435
 do_writepages+0x3c2/0x7b0 mm/page-writeback.c:2689
 filemap_fdatawrite_wbc+0x12c/0x190 mm/filemap.c:424
 __filemap_fdatawrite_range mm/filemap.c:457 [inline]
 file_write_and_wait_range+0x130/0x1f0 mm/filemap.c:814
 blkdev_fsync+0x77/0xd0 block/fops.c:551
 vfs_fsync_range+0x180/0x3a0 fs/sync.c:194
 generic_write_sync+0x19a/0x210 include/linux/fs.h:2888
 blkdev_write_iter+0x657/0x770 block/fops.c:728
 iter_file_splice_write+0x8fd/0x1100 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x279/0x4b0 fs/splice.c:1164
 splice_direct_to_actor+0x4fb/0xbc0 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0x182/0x270 fs/splice.c:1233
 do_sendfile+0x5c8/0xfb0 fs/read_write.c:1400
 __do_sys_sendfile64 fs/read_write.c:1467 [inline]
 __se_sys_sendfile64 fs/read_write.c:1453 [inline]
 __x64_sys_sendfile64+0x193/0x1f0 fs/read_write.c:1453
 x64_sys_call+0xa26/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f8d1358e929
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8d144d0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f8d137b5fa0 RCX: 00007f8d1358e929
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: 00007f8d13610b39 R08: 0000000000000000 R09: 0000000000000000
R10: 000000007ffff000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f8d137b5fa0 R15: 00007fff3d4e6a68
 </TASK>