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BUG: KCSAN: data-race in __blk_mq_requeue_request / bt_tags_for_each

write to 0xffff88810327cea0 of 4 bytes by task 3338 on cpu 0:
 __blk_mq_put_driver_tag block/blk-mq.h:306 [inline]
 blk_mq_put_driver_tag block/blk-mq.h:319 [inline]
 __blk_mq_requeue_request+0x9f/0x2b0 block/blk-mq.c:1417
 blk_mq_handle_dev_resource block/blk-mq.c:1903 [inline]
 blk_mq_dispatch_rq_list+0x973/0x11b0 block/blk-mq.c:2044
 __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+0x69a/0xdd0 block/blk-mq-sched.c:309
 blk_mq_sched_dispatch_requests+0x99/0x100 block/blk-mq-sched.c:333
 blk_mq_run_hw_queue+0x29c/0x4c0 block/blk-mq.c:2249
 blk_mq_get_tag+0x21f/0x590 block/blk-mq-tag.c:170
 __blk_mq_alloc_requests+0x5b9/0x850 block/blk-mq.c:498
 blk_mq_get_new_requests block/blk-mq.c:2874 [inline]
 blk_mq_submit_bio+0x46e/0xd70 block/blk-mq.c:2971
 __submit_bio+0x11c/0x350 block/blk-core.c:598
 __submit_bio_noacct_mq block/blk-core.c:677 [inline]
 submit_bio_noacct_nocheck+0x449/0x5e0 block/blk-core.c:706
 submit_bio_noacct+0x700/0x8a0 block/blk-core.c:800
 submit_bio+0xb7/0xc0 block/blk-core.c:833
 ext4_io_submit+0x8a/0xa0 fs/ext4/page-io.c:378
 ext4_do_writepages+0xb77/0x21e0 fs/ext4/inode.c:2697
 ext4_writepages+0x15e/0x2e0 fs/ext4/inode.c:2766
 do_writepages+0x1c5/0x340 mm/page-writeback.c:2553
 __writeback_single_inode+0x91/0x860 fs/fs-writeback.c:1603
 writeback_sb_inodes+0x511/0xaa0 fs/fs-writeback.c:1894
 wb_writeback+0x252/0x6e0 fs/fs-writeback.c:2070
 wb_do_writeback fs/fs-writeback.c:2217 [inline]
 wb_workfn+0x1a8/0x8d0 fs/fs-writeback.c:2257
 process_one_work+0x434/0x860 kernel/workqueue.c:2600
 worker_thread+0x5f2/0xa10 kernel/workqueue.c:2751
 kthread+0x1d7/0x210 kernel/kthread.c:389
 ret_from_fork+0x2e/0x40 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

read to 0xffff88810327cea0 of 4 bytes by task 15672 on cpu 1:
 blk_mq_find_and_get_req block/blk-mq-tag.c:260 [inline]
 bt_tags_iter block/blk-mq-tag.c:356 [inline]
 __sbitmap_for_each_set include/linux/sbitmap.h:281 [inline]
 sbitmap_for_each_set include/linux/sbitmap.h:302 [inline]
 bt_tags_for_each+0x2e2/0x500 block/blk-mq-tag.c:391
 __blk_mq_all_tag_iter block/blk-mq-tag.c:402 [inline]
 blk_mq_tagset_busy_iter+0x114/0x150 block/blk-mq-tag.c:446
 scsi_host_busy+0x4f/0x80 drivers/scsi/hosts.c:604
 scsi_host_queue_ready drivers/scsi/scsi_lib.c:1346 [inline]
 scsi_queue_rq+0x310/0x1a30 drivers/scsi/scsi_lib.c:1740
 blk_mq_dispatch_rq_list+0x7b1/0x11b0 block/blk-mq.c:2035
 __blk_mq_sched_dispatch_requests+0x1d4/0xdd0 block/blk-mq-sched.c:301
 blk_mq_sched_dispatch_requests+0x99/0x100 block/blk-mq-sched.c:333
 blk_mq_run_hw_queue+0x29c/0x4c0 block/blk-mq.c:2249
 blk_mq_get_tag+0x479/0x590 block/blk-mq-tag.c:170
 __blk_mq_alloc_requests+0x5b9/0x850 block/blk-mq.c:498
 blk_mq_get_new_requests block/blk-mq.c:2874 [inline]
 blk_mq_submit_bio+0x46e/0xd70 block/blk-mq.c:2971
 __submit_bio+0x11c/0x350 block/blk-core.c:598
 __submit_bio_noacct_mq block/blk-core.c:677 [inline]
 submit_bio_noacct_nocheck+0x449/0x5e0 block/blk-core.c:706
 submit_bio_noacct+0x700/0x8a0 block/blk-core.c:800
 submit_bio+0xb7/0xc0 block/blk-core.c:833
 ext4_io_submit+0x8a/0xa0 fs/ext4/page-io.c:378
 ext4_do_writepages+0xb77/0x21e0 fs/ext4/inode.c:2697
 ext4_writepages+0x15e/0x2e0 fs/ext4/inode.c:2766
 do_writepages+0x1c5/0x340 mm/page-writeback.c:2553
 filemap_fdatawrite_wbc+0xdb/0xf0 mm/filemap.c:393
 __filemap_fdatawrite_range mm/filemap.c:426 [inline]
 __filemap_fdatawrite mm/filemap.c:432 [inline]
 filemap_flush+0x95/0xc0 mm/filemap.c:459
 ext4_alloc_da_blocks+0x50/0x130 fs/ext4/inode.c:3033
 ext4_release_file+0x5f/0x1c0 fs/ext4/file.c:169
 __fput+0x2fd/0x600 fs/file_table.c:384
 ____fput+0x15/0x20 fs/file_table.c:412
 task_work_run+0x135/0x1a0 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0x5ff/0x1670 kernel/exit.c:874
 do_group_exit+0x101/0x150 kernel/exit.c:1024
 get_signal+0xeb7/0xff0 kernel/signal.c:2881
 arch_do_signal_or_restart+0x89/0x2a0 arch/x86/kernel/signal.c:308
 exit_to_user_mode_loop+0x6f/0xe0 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 irqentry_exit_to_user_mode+0x9/0x20 kernel/entry/common.c:310
 irqentry_exit+0x12/0x40 kernel/entry/common.c:413
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

value changed: 0x000002e4 -> 0xffffffff

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 15672 Comm: syz-executor.2 Not tainted 6.5.0-rc6-syzkaller-00027-g91aa6c412d7f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
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