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BUG: KCSAN: data-race in __mark_inode_dirty / __mark_inode_dirty

read-write to 0xffff88814f1f9d30 of 8 bytes by task 10304 on cpu 1:
 __mark_inode_dirty+0x1ee/0x620 fs/fs-writeback.c:2417
 mark_buffer_dirty+0x176/0x390 fs/buffer.c:1109
 __block_commit_write+0x10d/0x1b0 fs/buffer.c:2080
 block_write_end fs/buffer.c:2159 [inline]
 generic_write_end+0x81/0x350 fs/buffer.c:2173
 fat_write_end+0x4a/0x150 fs/fat/inode.c:249
 generic_perform_write+0x264/0x3f0 mm/filemap.c:3749
 __generic_file_write_iter+0xe3/0x280 mm/filemap.c:3866
 generic_file_write_iter+0x79/0x1c0 mm/filemap.c:3898
 do_iter_write+0x494/0x750 fs/read_write.c:855
 vfs_iter_write+0x4c/0x70 fs/read_write.c:896
 iter_file_splice_write+0x44a/0x7c0 fs/splice.c:686
 do_splice_from fs/splice.c:764 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:931
 splice_direct_to_actor+0x305/0x620 fs/splice.c:886
 do_splice_direct+0xfb/0x180 fs/splice.c:974
 do_sendfile+0x3bf/0x910 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1311 [inline]
 __se_sys_sendfile64 fs/read_write.c:1303 [inline]
 __x64_sys_sendfile64+0xb9/0x150 fs/read_write.c:1303
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88814f1f9d30 of 8 bytes by task 10305 on cpu 0:
 __mark_inode_dirty+0xd5/0x620 fs/fs-writeback.c:2402
 fat_update_time+0x2c9/0x300 fs/fat/misc.c:359
 inode_update_time fs/inode.c:1868 [inline]
 touch_atime+0x16e/0x2e0 fs/inode.c:1941
 file_accessed include/linux/fs.h:2521 [inline]
 generic_file_splice_read+0x136/0x2b0 fs/splice.c:312
 do_splice_to fs/splice.c:793 [inline]
 splice_direct_to_actor+0x26c/0x620 fs/splice.c:865
 do_splice_direct+0xfb/0x180 fs/splice.c:974
 do_sendfile+0x3bf/0x910 fs/read_write.c:1249
 __do_sys_sendfile64 fs/read_write.c:1317 [inline]
 __se_sys_sendfile64 fs/read_write.c:1303 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1303
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000000001 -> 0x0000000000000007

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10305 Comm: syz-executor.5 Not tainted 5.19.0-syzkaller-13236-g426b4ca2d6a5-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
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