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BUG: KCSAN: data-race in wbt_issue / wbt_issue

write to 0xffff8881037f1a28 of 8 bytes by task 15485 on cpu 1:
 wbt_issue+0xbd/0xd0 block/blk-wbt.c:611
 __rq_qos_issue+0x3b/0x70 block/blk-rq-qos.c:54
 rq_qos_issue block/blk-rq-qos.h:159 [inline]
 blk_mq_start_request+0xd0/0x230 block/blk-mq.c:721
 scsi_queue_rq+0x1191/0x14c0 drivers/scsi/scsi_lib.c:1691
 blk_mq_dispatch_rq_list+0x570/0xe80 block/blk-mq.c:1369
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:186 [inline]
 blk_mq_do_dispatch_sched+0x370/0x610 block/blk-mq-sched.c:199
 __blk_mq_sched_dispatch_requests+0x1fd/0x2a0 block/blk-mq-sched.c:310
 blk_mq_sched_dispatch_requests+0x9f/0x110 block/blk-mq-sched.c:341
 __blk_mq_run_hw_queue+0xc1/0x140 block/blk-mq.c:1488
 __blk_mq_delay_run_hw_queue+0x188/0x330 block/blk-mq.c:1565
 blk_mq_run_hw_queue+0x231/0x260 block/blk-mq.c:1618
 blk_mq_sched_insert_requests+0x144/0x210 block/blk-mq-sched.c:491
 blk_mq_flush_plug_list+0x2f5/0x400 block/blk-mq.c:1942
 blk_flush_plug_list+0x235/0x260 block/blk-core.c:1749
 blk_finish_plug+0x44/0x60 block/blk-core.c:1766
 __iomap_dio_rw+0x6a5/0xa30 fs/iomap/direct-io.c:575
 iomap_dio_rw+0x30/0x70 fs/iomap/direct-io.c:641
 ext4_dio_read_iter fs/ext4/file.c:77 [inline]
 ext4_file_read_iter+0x3bb/0x420 fs/ext4/file.c:128
 call_read_iter include/linux/fs.h:1971 [inline]
 generic_file_splice_read+0x22a/0x310 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+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x7a6/0xe20 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881037f1a28 of 8 bytes by task 15479 on cpu 0:
 wbt_issue+0x76/0xd0 block/blk-wbt.c:609
 __rq_qos_issue+0x3b/0x70 block/blk-rq-qos.c:54
 rq_qos_issue block/blk-rq-qos.h:159 [inline]
 blk_mq_start_request+0xd0/0x230 block/blk-mq.c:721
 scsi_queue_rq+0x1191/0x14c0 drivers/scsi/scsi_lib.c:1691
 blk_mq_dispatch_rq_list+0x570/0xe80 block/blk-mq.c:1369
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:186 [inline]
 blk_mq_do_dispatch_sched+0x370/0x610 block/blk-mq-sched.c:199
 __blk_mq_sched_dispatch_requests+0x1fd/0x2a0 block/blk-mq-sched.c:310
 blk_mq_sched_dispatch_requests+0x9f/0x110 block/blk-mq-sched.c:341
 __blk_mq_run_hw_queue+0xc1/0x140 block/blk-mq.c:1488
 __blk_mq_delay_run_hw_queue+0x188/0x330 block/blk-mq.c:1565
 blk_mq_run_hw_queue+0x231/0x260 block/blk-mq.c:1618
 blk_mq_sched_insert_requests+0x144/0x210 block/blk-mq-sched.c:491
 blk_mq_flush_plug_list+0x2f5/0x400 block/blk-mq.c:1942
 blk_flush_plug_list+0x235/0x260 block/blk-core.c:1749
 blk_finish_plug+0x44/0x60 block/blk-core.c:1766
 __iomap_dio_rw+0x6a5/0xa30 fs/iomap/direct-io.c:575
 iomap_dio_rw+0x30/0x70 fs/iomap/direct-io.c:641
 ext4_dio_read_iter fs/ext4/file.c:77 [inline]
 ext4_file_read_iter+0x3bb/0x420 fs/ext4/file.c:128
 call_read_iter include/linux/fs.h:1971 [inline]
 generic_file_splice_read+0x22a/0x310 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+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x7a6/0xe20 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 15479 Comm: syz-executor.2 Not tainted 5.12.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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