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BUG: KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_request_bypass_insert

write to 0xffff888102826210 of 8 bytes by task 227 on cpu 1:
 __list_add include/linux/list.h:72 [inline]
 list_add include/linux/list.h:88 [inline]
 blk_mq_request_bypass_insert+0x6a/0x130 block/blk-mq.c:2345
 blk_mq_sched_insert_request+0xfd/0x220 block/blk-mq-sched.c:434
 blk_mq_requeue_work+0x38b/0x3f0 block/blk-mq.c:1306
 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307
 worker_thread+0x616/0xa70 kernel/workqueue.c:2454
 kthread+0x1bf/0x1e0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30

read to 0xffff888102826210 of 8 bytes by task 20369 on cpu 0:
 list_empty_careful include/linux/list.h:329 [inline]
 __blk_mq_sched_dispatch_requests+0x80/0x270 block/blk-mq-sched.c:277
 blk_mq_sched_dispatch_requests+0x9f/0x110 block/blk-mq-sched.c:332
 __blk_mq_run_hw_queue+0x7e/0x100 block/blk-mq.c:1968
 __blk_mq_delay_run_hw_queue+0x19c/0x390 block/blk-mq.c:2045
 blk_mq_run_hw_queue+0x180/0x310 block/blk-mq.c:2096
 blk_mq_sched_insert_requests+0x1cc/0x2a0 block/blk-mq-sched.c:486
 blk_mq_flush_plug_list+0x5c3/0x6c0 block/blk-mq.c:2628
 blk_flush_plug+0x25a/0x2b0 block/blk-core.c:1282
 blk_finish_plug+0x44/0x60 block/blk-core.c:1306
 __iomap_dio_rw+0xcb5/0x10a0 fs/iomap/direct-io.c:598
 iomap_dio_rw+0x38/0x80 fs/iomap/direct-io.c:680
 ext4_dio_read_iter fs/ext4/file.c:77 [inline]
 ext4_file_read_iter+0x190/0x1f0 fs/ext4/file.c:128
 call_read_iter include/linux/fs.h:2068 [inline]
 generic_file_splice_read+0x24f/0x330 fs/splice.c:311
 do_splice_to fs/splice.c:796 [inline]
 splice_direct_to_actor+0x2aa/0x650 fs/splice.c:870
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0xffff888102826208 -> 0xffff8881025cc448

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 20369 Comm: syz-executor.3 Not tainted 5.17.0-rc4-syzkaller-00069-ga3580ac9b7a3-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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