==================================================================
BUG: KCSAN: data-race in blk_mq_request_bypass_insert / blk_mq_run_hw_queue

write to 0xffff8881021bec10 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:359
 ret_from_fork+0x1f/0x30

read to 0xffff8881021bec10 of 8 bytes by task 19023 on cpu 0:
 list_empty_careful include/linux/list.h:321 [inline]
 blk_mq_hctx_has_pending block/blk-mq.c:100 [inline]
 blk_mq_run_hw_queue+0x19b/0x310 block/blk-mq.c:2091
 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:1269
 io_schedule_prepare kernel/sched/core.c:8382 [inline]
 io_schedule+0x32/0x50 kernel/sched/core.c:8413
 bit_wait_io+0x8/0x50 kernel/sched/wait_bit.c:209
 __wait_on_bit kernel/sched/wait_bit.c:49 [inline]
 out_of_line_wait_on_bit+0xd6/0x130 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:101 [inline]
 do_get_write_access+0x6e/0x640 fs/jbd2/transaction.c:1098
 jbd2_journal_get_write_access+0xcc/0x150 fs/jbd2/transaction.c:1233
 __ext4_journal_get_write_access+0x132/0x370 fs/ext4/ext4_jbd2.c:235
 ext4_mb_mark_diskspace_used+0xbd/0x8f0 fs/ext4/mballoc.c:3799
 ext4_mb_new_blocks+0x6f5/0x14a0 fs/ext4/mballoc.c:5600
 ext4_ext_map_blocks+0x1107/0x1940 fs/ext4/extents.c:4282
 ext4_map_blocks+0x55e/0xb90 fs/ext4/inode.c:638
 mpage_map_one_extent+0xbd/0x2a0 fs/ext4/inode.c:2373
 mpage_map_and_submit_extent fs/ext4/inode.c:2426 [inline]
 ext4_writepages+0xa4e/0x1a60 fs/ext4/inode.c:2778
 do_writepages+0x1cb/0x330 mm/page-writeback.c:2364
 filemap_fdatawrite_wbc mm/filemap.c:395 [inline]
 __filemap_fdatawrite_range mm/filemap.c:428 [inline]
 file_write_and_wait_range+0x134/0x1d0 mm/filemap.c:786
 ext4_sync_file+0xad/0x570 fs/ext4/fsync.c:151
 vfs_fsync_range+0x107/0x120 fs/sync.c:182
 generic_write_sync include/linux/fs.h:2896 [inline]
 ext4_buffered_write_iter+0x243/0x290 fs/ext4/file.c:275
 ext4_file_write_iter+0x227/0xda0
 call_write_iter include/linux/fs.h:2086 [inline]
 do_iter_readv_writev+0x2de/0x380 fs/read_write.c:725
 do_iter_write+0x192/0x5c0 fs/read_write.c:851
 vfs_iter_write+0x4c/0x70 fs/read_write.c:892
 iter_file_splice_write+0x43a/0x790 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 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:1304 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0xb9/0x140 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: 0xffff8881021bec08 -> 0xffff88810283f848

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 19023 Comm: syz-executor.2 Not tainted 5.16.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
syz-executor.2 (19023) used greatest stack depth: 9024 bytes left