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BUG: KCSAN: data-race in __ext4_journal_start_sb / jbd2_journal_update_sb_log_tail

write to 0xffff888102fcd800 of 8 bytes by task 1404 on cpu 1:
 jbd2_journal_update_sb_log_tail+0x176/0x1b0 fs/jbd2/journal.c:1689
 jbd2_journal_commit_transaction+0x21e/0x3460 fs/jbd2/commit.c:430
 kjournald2+0x263/0x480 fs/jbd2/journal.c:213
 kthread+0x2c7/0x2e0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30

read to 0xffff888102fcd800 of 8 bytes by task 32049 on cpu 0:
 is_journal_aborted include/linux/jbd2.h:1695 [inline]
 ext4_journal_check_start fs/ext4/ext4_jbd2.c:82 [inline]
 __ext4_journal_start_sb+0xf2/0x310 fs/ext4/ext4_jbd2.c:98
 __ext4_journal_start fs/ext4/ext4_jbd2.h:326 [inline]
 ext4_dirty_inode+0x58/0xa0 fs/ext4/inode.c:5916
 __mark_inode_dirty+0x72/0x6c0 fs/fs-writeback.c:2399
 mark_inode_dirty include/linux/fs.h:2451 [inline]
 generic_write_end+0x157/0x180 fs/buffer.c:2202
 ext4_da_write_end+0x4de/0x630 fs/ext4/inode.c:3059
 generic_perform_write+0x261/0x400 mm/filemap.c:3767
 ext4_buffered_write_iter+0x25b/0x380 fs/ext4/file.c:269
 ext4_file_write_iter+0x2e7/0x1200
 call_write_iter include/linux/fs.h:2162 [inline]
 new_sync_write fs/read_write.c:503 [inline]
 vfs_write+0x7f5/0x950 fs/read_write.c:590
 ksys_write+0xd9/0x190 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:652
 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: 0x0000000000000038 -> 0x0000000000000230

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 32049 Comm: syz-executor.1 Not tainted 5.15.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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