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BUG: KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_dispatch_rq_list

write to 0xffff888100fc60f8 of 4 bytes by task 78 on cpu 1:
 blk_mq_dispatch_rq_list+0xf53/0x10a0
 __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+0x5ec/0xd20 block/blk-mq-sched.c:309
 blk_mq_sched_dispatch_requests+0x78/0xe0 block/blk-mq-sched.c:331
 blk_mq_run_work_fn+0x65/0xe0 block/blk-mq.c:2456
 process_one_work kernel/workqueue.c:2633 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2706
 worker_thread+0x525/0x730 kernel/workqueue.c:2787
 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 0xffff888100fc60f8 of 4 bytes by task 5810 on cpu 0:
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:97 [inline]
 blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline]
 __blk_mq_sched_dispatch_requests+0x28b/0xd20 block/blk-mq-sched.c:309
 blk_mq_sched_dispatch_requests+0x78/0xe0 block/blk-mq-sched.c:331
 blk_mq_run_hw_queue+0x298/0x4c0 block/blk-mq.c:2286
 blk_mq_flush_plug_list+0x7a7/0xdb0 block/blk-mq.c:2834
 __blk_flush_plug+0x210/0x260 block/blk-core.c:1166
 blk_finish_plug+0x47/0x60 block/blk-core.c:1190
 __flush_batch fs/jbd2/checkpoint.c:129 [inline]
 jbd2_log_do_checkpoint+0x611/0xa50 fs/jbd2/checkpoint.c:281
 __jbd2_log_wait_for_space+0x234/0x460 fs/jbd2/checkpoint.c:88
 add_transaction_credits fs/jbd2/transaction.c:298 [inline]
 start_this_handle+0x9b3/0x10f0 fs/jbd2/transaction.c:422
 jbd2__journal_start+0x1d8/0x3d0 fs/jbd2/transaction.c:520
 __ext4_journal_start_sb+0x16d/0x430 fs/ext4/ext4_jbd2.c:112
 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline]
 ext4_dirty_inode+0x5f/0xb0 fs/ext4/inode.c:5969
 __mark_inode_dirty+0x169/0x7d0 fs/fs-writeback.c:2452
 generic_update_time fs/inode.c:1905 [inline]
 inode_update_time fs/inode.c:1918 [inline]
 __file_update_time fs/inode.c:2106 [inline]
 file_modified_flags+0x1ac/0x1d0 fs/inode.c:2177
 file_modified+0x17/0x20 fs/inode.c:2193
 ext4_write_checks fs/ext4/file.c:279 [inline]
 ext4_buffered_write_iter+0x1d8/0x370 fs/ext4/file.c:295
 ext4_file_write_iter+0x297/0xe10
 __kernel_write_iter+0x25f/0x480 fs/read_write.c:523
 dump_emit_page fs/coredump.c:888 [inline]
 dump_user_range+0x25d/0x480 fs/coredump.c:915
 elf_core_dump+0x1a85/0x1ba0 fs/binfmt_elf.c:2077
 do_coredump+0x102a/0x1890 fs/coredump.c:764
 get_signal+0xdb5/0x10a0 kernel/signal.c:2879
 arch_do_signal_or_restart+0x95/0x4b0 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop kernel/entry/common.c:105 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 irqentry_exit_to_user_mode+0x98/0x130 kernel/entry/common.c:225
 irqentry_exit+0x12/0x40 kernel/entry/common.c:328
 exc_general_protection+0x339/0x4c0 arch/x86/kernel/traps.c:643
 asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:564

value changed: 0x00000002 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5810 Comm: syz-executor.4 Not tainted 6.8.0-rc1-syzkaller-00037-g443b349019f2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
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