BUG: sleeping function called from invalid context at kernel/locking/mutex.c:623
in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 19399, name: syz.6.4428
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
7 locks held by syz.6.4428/19399:
 #0: ffff888030e500f0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1259
 #1: ffff88801d756450 (sb_writers#12){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
 #1: ffff88801d756450 (sb_writers#12){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683
 #2: ffff888029822280 (&buffer->mutex){+.+.}-{4:4}, at: configfs_write_iter+0x7e/0x430 fs/configfs/file.c:226
 #3: ffff888057f6c870 (&p->frag_sem){.+.+}-{4:4}, at: flush_write_buffer fs/configfs/file.c:205 [inline]
 #3: ffff888057f6c870 (&p->frag_sem){.+.+}-{4:4}, at: configfs_write_iter+0x238/0x430 fs/configfs/file.c:229
 #4: ffffffff9aaec560 (&lock){+.+.}-{4:4}, at: nullb_device_power_store+0xdb/0x380 drivers/block/null_blk/main.c:496
 #5: ffff888051072350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xde/0xd70 block/bdev.c:948
 #6: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #6: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #6: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: blk_mq_submit_bio+0x1c8a/0x2a40 block/blk-mq.c:3208
CPU: 0 UID: 0 PID: 19399 Comm: syz.6.4428 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 __might_resched+0x378/0x4d0 kernel/sched/core.c:9197
 __mutex_lock_common kernel/locking/mutex.c:623 [inline]
 __mutex_lock+0x118/0x1550 kernel/locking/mutex.c:821
 null_lock_zone drivers/block/null_blk/zoned.c:39 [inline]
 null_process_zoned_cmd+0x6f6/0xf80 drivers/block/null_blk/zoned.c:732
 null_handle_cmd drivers/block/null_blk/main.c:1455 [inline]
 null_queue_rq+0x8bc/0xe70 drivers/block/null_blk/main.c:1703
 __blk_mq_issue_directly block/blk-mq.c:2694 [inline]
 blk_mq_try_issue_directly+0x3f4/0x880 block/blk-mq.c:2754
 blk_mq_submit_bio+0x20c0/0x2a40 block/blk-mq.c:3208
 __submit_bio_noacct_mq block/blk-core.c:756 [inline]
 submit_bio_noacct_nocheck+0x2f4/0xa40 block/blk-core.c:790
 bh_submit fs/buffer.c:1239 [inline]
 block_read_full_folio+0x7a6/0x810 fs/buffer.c:2463
 filemap_read_folio+0x12c/0x3a0 mm/filemap.c:2516
 do_read_cache_folio+0x354/0x590 mm/filemap.c:4146
 read_mapping_folio include/linux/pagemap.h:1015 [inline]
 read_part_sector+0xb6/0x2b0 block/partitions/core.c:724
 adfspart_check_ICS+0xb1/0x960 block/partitions/acorn.c:357
 check_partition block/partitions/core.c:143 [inline]
 blk_add_partitions block/partitions/core.c:591 [inline]
 bdev_disk_changed+0x851/0x17a0 block/partitions/core.c:695
 blkdev_get_whole+0x372/0x510 block/bdev.c:751
 bdev_open+0x324/0xd70 block/bdev.c:960
 bdev_file_open_by_dev+0x1be/0x240 block/bdev.c:1062
 disk_scan_partitions+0x1bb/0x2c0 block/genhd.c:387
 add_disk_final block/genhd.c:412 [inline]
 add_disk_fwnode+0x24b/0x3a0 block/genhd.c:606
 add_disk include/linux/blkdev.h:800 [inline]
 null_add_dev+0x130b/0x1d70 drivers/block/null_blk/main.c:2052
 nullb_device_power_store+0x240/0x380 drivers/block/null_blk/main.c:501
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x337/0x430 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x612/0xba0 fs/read_write.c:687
 ksys_write+0x150/0x270 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f95ef39e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f95f019b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f95ef625fa0 RCX: 00007f95ef39e0d9
RDX: 0000000000000002 RSI: 0000200000000700 RDI: 0000000000000005
RBP: 00007f95ef435024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f95ef626038 R14: 00007f95ef625fa0 R15: 00007ffe19f02fb8
 </TASK>
------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(lock->magic != lock)
WARNING: kernel/locking/mutex.c:625 at __mutex_lock_common kernel/locking/mutex.c:625 [inline], CPU#0: syz.6.4428/19399
WARNING: kernel/locking/mutex.c:625 at __mutex_lock+0x12d8/0x1550 kernel/locking/mutex.c:821, CPU#0: syz.6.4428/19399
Modules linked in:

CPU: 0 UID: 0 PID: 19399 Comm: syz.6.4428 Tainted: G        W    L      syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:625 [inline]
RIP: 0010:__mutex_lock+0x12df/0x1550 kernel/locking/mutex.c:821
Code: 7a 57 90 48 c1 e8 03 0f b6 04 18 84 c0 0f 85 47 02 00 00 83 3d 45 38 85 04 00 75 13 48 8d 3d c8 87 88 04 48 c7 c6 40 f7 ec 8b <67> 48 0f b9 3a 90 e9 75 ee ff ff 90 0f 0b 90 e9 48 f2 ff ff 90 0f
RSP: 0018:ffffc9001182ed40 EFLAGS: 00010246
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000080000
RDX: ffffc90012289000 RSI: ffffffff8becf740 RDI: ffffffff905ac9d0
RBP: ffffc9001182eed0 R08: ffffffff90577a43 R09: 1ffffffff20aef48
R10: dffffc0000000000 R11: fffffbfff20aef49 R12: ffff88804b9c0000
R13: 0000000000000000 R14: 1ffff92002305dbc R15: 0000000000000000
FS:  00007f95f019b6c0(0000) GS:ffff888124f55000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f81bff8 CR3: 000000007cb27000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 null_lock_zone drivers/block/null_blk/zoned.c:39 [inline]
 null_process_zoned_cmd+0x6f6/0xf80 drivers/block/null_blk/zoned.c:732
 null_handle_cmd drivers/block/null_blk/main.c:1455 [inline]
 null_queue_rq+0x8bc/0xe70 drivers/block/null_blk/main.c:1703
 __blk_mq_issue_directly block/blk-mq.c:2694 [inline]
 blk_mq_try_issue_directly+0x3f4/0x880 block/blk-mq.c:2754
 blk_mq_submit_bio+0x20c0/0x2a40 block/blk-mq.c:3208
 __submit_bio_noacct_mq block/blk-core.c:756 [inline]
 submit_bio_noacct_nocheck+0x2f4/0xa40 block/blk-core.c:790
 bh_submit fs/buffer.c:1239 [inline]
 block_read_full_folio+0x7a6/0x810 fs/buffer.c:2463
 filemap_read_folio+0x12c/0x3a0 mm/filemap.c:2516
 do_read_cache_folio+0x354/0x590 mm/filemap.c:4146
 read_mapping_folio include/linux/pagemap.h:1015 [inline]
 read_part_sector+0xb6/0x2b0 block/partitions/core.c:724
 adfspart_check_ICS+0xb1/0x960 block/partitions/acorn.c:357
 check_partition block/partitions/core.c:143 [inline]
 blk_add_partitions block/partitions/core.c:591 [inline]
 bdev_disk_changed+0x851/0x17a0 block/partitions/core.c:695
 blkdev_get_whole+0x372/0x510 block/bdev.c:751
 bdev_open+0x324/0xd70 block/bdev.c:960
 bdev_file_open_by_dev+0x1be/0x240 block/bdev.c:1062
 disk_scan_partitions+0x1bb/0x2c0 block/genhd.c:387
 add_disk_final block/genhd.c:412 [inline]
 add_disk_fwnode+0x24b/0x3a0 block/genhd.c:606
 add_disk include/linux/blkdev.h:800 [inline]
 null_add_dev+0x130b/0x1d70 drivers/block/null_blk/main.c:2052
 nullb_device_power_store+0x240/0x380 drivers/block/null_blk/main.c:501
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x337/0x430 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x612/0xba0 fs/read_write.c:687
 ksys_write+0x150/0x270 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f95ef39e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f95f019b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f95ef625fa0 RCX: 00007f95ef39e0d9
RDX: 0000000000000002 RSI: 0000200000000700 RDI: 0000000000000005
RBP: 00007f95ef435024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f95ef626038 R14: 00007f95ef625fa0 R15: 00007ffe19f02fb8
 </TASK>
----------------
Code disassembly (best guess):
   0:	7a 57                	jp     0x59
   2:	90                   	nop
   3:	48 c1 e8 03          	shr    $0x3,%rax
   7:	0f b6 04 18          	movzbl (%rax,%rbx,1),%eax
   b:	84 c0                	test   %al,%al
   d:	0f 85 47 02 00 00    	jne    0x25a
  13:	83 3d 45 38 85 04 00 	cmpl   $0x0,0x4853845(%rip)        # 0x485385f
  1a:	75 13                	jne    0x2f
  1c:	48 8d 3d c8 87 88 04 	lea    0x48887c8(%rip),%rdi        # 0x48887eb
  23:	48 c7 c6 40 f7 ec 8b 	mov    $0xffffffff8becf740,%rsi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	90                   	nop
  30:	e9 75 ee ff ff       	jmp    0xffffeeaa
  35:	90                   	nop
  36:	0f 0b                	ud2
  38:	90                   	nop
  39:	e9 48 f2 ff ff       	jmp    0xfffff286
  3e:	90                   	nop
  3f:	0f                   	.byte 0xf