syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7687/2:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=26977, q=1065346 ncpus=2)
task:syz.3.721       state:R  running task     stack:23608 pid:7687  tgid:7687  ppid:5612   task_flags:0x2040004c flags:0x00080001
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x1295/0x67a0 kernel/sched/core.c:7189
 preempt_schedule_irq+0x50/0x90 kernel/sched/core.c:7513
 irqentry_exit_to_kernel_mode_preempt include/linux/irq-entry-common.h:468 [inline]
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
 irqentry_exit+0x205/0x970 kernel/entry/common.c:164
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x5e/0x370 kernel/locking/lockdep.c:5872
Code: 05 fb 03 25 12 83 f8 07 0f 87 d9 02 00 00 48 0f a3 05 06 8e f2 0e 0f 82 a4 02 00 00 8b 35 8e c1 f2 0e 85 f6 0f 85 bf 00 00 00 <48> 8b 44 24 30 65 48 2b 05 9d 03 25 12 0f 85 ed 02 00 00 48 83 c4
RSP: 0018:ffffc9000848e778 EFLAGS: 00000206
RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8deea69a RDI: ffffffff8c1c4780
RBP: ffffffff8e7e5560 R08: 00000000eda37e47 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 rcu_read_lock include/linux/rcupdate.h:838 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1181 [inline]
 unwind_next_frame+0xd1/0x2090 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4570 [inline]
 slab_alloc_node mm/slub.c:4899 [inline]
 kmem_cache_alloc_noprof+0x241/0x6e0 mm/slub.c:4906
 kmem_alloc_batch+0x49/0x170 lib/debugobjects.c:371
 fill_pool lib/debugobjects.c:420 [inline]
 debug_objects_fill_pool lib/debugobjects.c:752 [inline]
 debug_objects_fill_pool+0x24d/0x5a0 lib/debugobjects.c:723
 debug_object_activate+0x103/0x490 lib/debugobjects.c:841
 debug_rcu_head_queue kernel/rcu/rcu.h:236 [inline]
 __call_rcu_common.constprop.0+0x35/0x9b0 kernel/rcu/tree.c:3116
 slab_free_hook mm/slub.c:2653 [inline]
 slab_free mm/slub.c:6251 [inline]
 kmem_cache_free+0x44a/0x6c0 mm/slub.c:6378
 mempool_free+0xde/0x130 mm/mempool.c:711
 bio_put_percpu_cache block/bio.c:823 [inline]
 bio_put+0x34f/0x5b0 block/bio.c:842
 bio_endio+0x78f/0x8f0 block/bio.c:1798
 blk_update_request+0x741/0x1380 block/blk-mq.c:1016
 blk_mq_end_request+0x5b/0x420 block/blk-mq.c:1178
 blk_mq_complete_request block/blk-mq.c:1356 [inline]
 blk_mq_complete_request+0x8b/0xb0 block/blk-mq.c:1353
 nullb_complete_cmd drivers/block/null_blk/main.c:1412 [inline]
 null_handle_cmd drivers/block/null_blk/main.c:1464 [inline]
 null_queue_rq+0xb48/0xfb0 drivers/block/null_blk/main.c:1703
 null_queue_rqs+0xe9/0x2f0 drivers/block/null_blk/main.c:1717
 __blk_mq_flush_list block/blk-mq.c:2858 [inline]
 __blk_mq_flush_list+0x9a/0xc0 block/blk-mq.c:2854
 blk_mq_dispatch_queue_requests+0x184/0x7c0 block/blk-mq.c:2903
 blk_mq_flush_plug_list+0x1f2/0x600 block/blk-mq.c:2991
 blk_add_rq_to_plug+0x1ca/0x540 block/blk-mq.c:1417
 blk_mq_submit_bio+0x1e03/0x3010 block/blk-mq.c:3231
 __submit_bio+0x1e1/0x6c0 block/blk-core.c:635
 __submit_bio_noacct_mq block/blk-core.c:722 [inline]
 submit_bio_noacct_nocheck+0x543/0xbf0 block/blk-core.c:753
 submit_bio_noacct+0xd18/0x2000 block/blk-core.c:884
 blk_crypto_submit_bio include/linux/blk-crypto.h:203 [inline]
 submit_bh_wbc+0x681/0x890 fs/buffer.c:2737
 __block_write_full_folio+0x77f/0xee0 fs/buffer.c:1830
 block_write_full_folio+0x3b5/0x4e0 fs/buffer.c:2650
 blkdev_writepages+0xc7/0x150 block/fops.c:486
 do_writepages+0x278/0x600 mm/page-writeback.c:2571
 filemap_writeback+0x22d/0x2e0 mm/filemap.c:388
 filemap_fdatawrite_range mm/filemap.c:413 [inline]
 filemap_write_and_wait_range mm/filemap.c:685 [inline]
 filemap_write_and_wait_range+0xa6/0x130 mm/filemap.c:676
 filemap_write_and_wait include/linux/pagemap.h:65 [inline]
 sync_blockdev block/bdev.c:276 [inline]
 sync_blockdev block/bdev.c:272 [inline]
 bdev_release+0x4d3/0x6d0 block/bdev.c:1134
 blkdev_release+0x15/0x20 block/fops.c:705
 __fput+0x3ff/0xb50 fs/file_table.c:510
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x951/0x2af0 kernel/exit.c:976
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1119
 __do_sys_exit_group kernel/exit.c:1130 [inline]
 __se_sys_exit_group kernel/exit.c:1128 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1128
 x64_sys_call+0x102c/0x1530 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbf5119ce59
RSP: 002b:00007ffef5c63a38 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbf5119ce59
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffef5c63a9c R08: 0000000000000000 R09: 00000000000927c0
R10: 0000000000000006 R11: 0000000000000246 R12: 0000000000000099
R13: 00000000000927c0 R14: 0000000000025cc0 R15: 00007ffef5c63af0
 </TASK>