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BUG: KCSAN: data-race in __mod_timer / blk_add_timer

write to 0xffff8881017a0808 of 8 bytes by task 77 on cpu 1:
 __mod_timer+0x5fd/0x860 kernel/time/timer.c:1121
 mod_timer+0x1f/0x30 kernel/time/timer.c:1190
 blk_mq_timeout_work+0x185/0x350 block/blk-mq.c:1661
 process_one_work kernel/workqueue.c:2630 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
 worker_thread+0x525/0x730 kernel/workqueue.c:2784
 kthread+0x1d7/0x210 kernel/kthread.c:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

read to 0xffff8881017a0808 of 8 bytes by task 10726 on cpu 0:
 blk_add_timer+0x118/0x190
 blk_mq_start_request+0x10e/0x2d0 block/blk-mq.c:1260
 loop_queue_rq+0x4c/0x650 drivers/block/loop.c:1851
 __blk_mq_issue_directly block/blk-mq.c:2578 [inline]
 blk_mq_request_issue_directly+0x1d6/0x330 block/blk-mq.c:2663
 blk_mq_plug_issue_direct+0x156/0x520 block/blk-mq.c:2684
 blk_mq_flush_plug_list+0x2b6/0xdc0 block/blk-mq.c:2793
 blk_add_rq_to_plug+0x108/0x3e0 block/blk-mq.c:1294
 blk_mq_submit_bio+0x692/0xd70 block/blk-mq.c:2995
 __submit_bio+0x11c/0x350 block/blk-core.c:599
 __submit_bio_noacct_mq block/blk-core.c:678 [inline]
 submit_bio_noacct_nocheck+0x449/0x5e0 block/blk-core.c:707
 submit_bio_noacct+0x71c/0x8c0 block/blk-core.c:801
 submit_bio+0xb7/0xc0 block/blk-core.c:834
 submit_bh_wbc+0x2ca/0x300 fs/buffer.c:2821
 __block_write_full_folio+0x580/0x8a0 fs/buffer.c:1906
 block_write_full_page+0x2d3/0x390
 blkdev_writepage+0x24/0x30 block/fops.c:415
 writepage_cb+0x36/0xc0 mm/page-writeback.c:2537
 write_cache_pages+0x38d/0x740 mm/page-writeback.c:2474
 do_writepages+0x20f/0x340 mm/page-writeback.c:2558
 filemap_fdatawrite_wbc+0xdb/0xf0 mm/filemap.c:387
 __filemap_fdatawrite_range mm/filemap.c:420 [inline]
 file_write_and_wait_range+0xf4/0x190 mm/filemap.c:778
 blkdev_fsync+0x4e/0xa0 block/fops.c:529
 vfs_fsync_range+0x111/0x120 fs/sync.c:188
 generic_write_sync+0xf2/0x120 include/linux/fs.h:2653
 blkdev_write_iter+0x364/0x390 block/fops.c:700
 call_write_iter include/linux/fs.h:2020 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x48a/0x790 fs/read_write.c:584
 ksys_write+0xeb/0x1a0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000100041cf4 -> 0x0000000100042638

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10726 Comm: syz-executor.4 Tainted: G        W          6.7.0-rc1-syzkaller-00125-g7475e51b8796 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
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