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BUG: KCSAN: data-race in blk_mq_sched_dispatch_requests / blk_mq_sched_dispatch_requests

read-write to 0xffff8881003d4750 of 8 bytes by task 18786 on cpu 0:
 blk_mq_sched_dispatch_requests+0x8a/0x100 block/blk-mq-sched.c:327
 blk_mq_run_hw_queue+0x2a4/0x4c0 block/blk-mq.c:2264
 blk_mq_flush_plug_list+0x7b6/0xdc0 block/blk-mq.c:2812
 __blk_flush_plug+0x210/0x260 block/blk-core.c:1150
 blk_finish_plug+0x47/0x60 block/blk-core.c:1174
 __iomap_dio_rw+0xc69/0x1090 fs/iomap/direct-io.c:667
 iomap_dio_rw+0x40/0x90 fs/iomap/direct-io.c:748
 ext4_dio_read_iter fs/ext4/file.c:94 [inline]
 ext4_file_read_iter+0x21c/0x2a0 fs/ext4/file.c:145
 call_read_iter include/linux/fs.h:2078 [inline]
 copy_splice_read+0x26b/0x4b0 fs/splice.c:365
 do_splice_read fs/splice.c:984 [inline]
 splice_direct_to_actor+0x288/0x650 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x377/0x880 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read-write to 0xffff8881003d4750 of 8 bytes by task 18789 on cpu 1:
 blk_mq_sched_dispatch_requests+0x8a/0x100 block/blk-mq-sched.c:327
 blk_mq_run_hw_queue+0x2a4/0x4c0 block/blk-mq.c:2264
 blk_mq_flush_plug_list+0x7b6/0xdc0 block/blk-mq.c:2812
 __blk_flush_plug+0x210/0x260 block/blk-core.c:1150
 blk_finish_plug+0x47/0x60 block/blk-core.c:1174
 ext4_do_writepages+0x1bc7/0x2100 fs/ext4/inode.c:2736
 ext4_writepages+0x15e/0x2e0 fs/ext4/inode.c:2774
 do_writepages+0x1c2/0x340 mm/page-writeback.c:2553
 filemap_fdatawrite_wbc+0xdb/0xf0 mm/filemap.c:387
 __filemap_fdatawrite_range mm/filemap.c:420 [inline]
 filemap_write_and_wait_range+0xe0/0x210 mm/filemap.c:675
 kiocb_write_and_wait+0x79/0x110 mm/filemap.c:2688
 __iomap_dio_rw+0x4fe/0x1090 fs/iomap/direct-io.c:592
 iomap_dio_rw+0x40/0x90 fs/iomap/direct-io.c:748
 ext4_dio_read_iter fs/ext4/file.c:94 [inline]
 ext4_file_read_iter+0x21c/0x2a0 fs/ext4/file.c:145
 call_read_iter include/linux/fs.h:2078 [inline]
 copy_splice_read+0x26b/0x4b0 fs/splice.c:365
 do_splice_read fs/splice.c:984 [inline]
 splice_direct_to_actor+0x288/0x650 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x377/0x880 fs/read_write.c:1295
 __do_sys_sendfile64 fs/read_write.c:1362 [inline]
 __se_sys_sendfile64 fs/read_write.c:1348 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1348
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000000016d14 -> 0x0000000000016d15

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 18789 Comm: syz-executor.2 Tainted: G        W          6.7.0-syzkaller-00562-g9f8413c4a66f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
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