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BUG: KCSAN: data-race in blk_mq_sched_dispatch_requests / blk_mq_sched_dispatch_requests

read-write to 0xffff888100197950 of 8 bytes by task 2286 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
 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:388
 __filemap_fdatawrite_range mm/filemap.c:421 [inline]
 filemap_write_and_wait_range+0xe0/0x210 mm/filemap.c:676
 kiocb_write_and_wait+0x79/0x110 mm/filemap.c:2689
 __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:2079 [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 0xffff888100197950 of 8 bytes by task 2220 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_add_rq_to_plug+0x108/0x3e0 block/blk-mq.c:1294
 blk_mq_submit_bio+0x61a/0xd90 block/blk-mq.c:3008
 __submit_bio+0x11c/0x350 block/blk-core.c:607
 __submit_bio_noacct_mq block/blk-core.c:686 [inline]
 submit_bio_noacct_nocheck+0x4ad/0x5e0 block/blk-core.c:715
 submit_bio_noacct+0x70c/0x8c0 block/blk-core.c:809
 submit_bio+0xb7/0xc0 block/blk-core.c:842
 ext4_io_submit fs/ext4/page-io.c:378 [inline]
 io_submit_add_bh fs/ext4/page-io.c:419 [inline]
 ext4_bio_write_folio+0x6c0/0x9a0 fs/ext4/page-io.c:563
 mpage_submit_folio fs/ext4/inode.c:1875 [inline]
 mpage_map_and_submit_buffers fs/ext4/inode.c:2121 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2260 [inline]
 ext4_do_writepages+0x139f/0x2100 fs/ext4/inode.c:2685
 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:388
 __filemap_fdatawrite_range mm/filemap.c:421 [inline]
 __filemap_fdatawrite mm/filemap.c:427 [inline]
 filemap_flush+0x95/0xc0 mm/filemap.c:454
 ext4_alloc_da_blocks+0x50/0x130 fs/ext4/inode.c:3078
 ext4_release_file+0x5f/0x1c0 fs/ext4/file.c:169
 __fput+0x299/0x630 fs/file_table.c:381
 __fput_sync+0x44/0x50 fs/file_table.c:466
 __do_sys_close fs/open.c:1554 [inline]
 __se_sys_close+0xfa/0x1a0 fs/open.c:1539
 __x64_sys_close+0x1f/0x30 fs/open.c:1539
 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: 0x000000000003cc37 -> 0x000000000003cc38

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 2220 Comm: syz-executor.5 Not tainted 6.7.0-syzkaller-02723-gde927f6c0b07 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
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