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BUG: KCSAN: data-race in __mark_inode_dirty / __mark_inode_dirty

write to 0xffff88813fd7ad70 of 8 bytes by task 10368 on cpu 1:
 __mark_inode_dirty+0x250/0x7d0 fs/fs-writeback.c:2455
 fat_update_time+0x28e/0x2c0 fs/fat/misc.c:359
 inode_update_time fs/inode.c:1913 [inline]
 touch_atime+0x18c/0x310 fs/inode.c:1986
 file_accessed include/linux/fs.h:2203 [inline]
 filemap_splice_read+0x758/0x810 mm/filemap.c:2986
 vfs_splice_read fs/splice.c:889 [inline]
 splice_direct_to_actor+0x2a2/0x660 fs/splice.c:961
 do_splice_direct+0x104/0x180 fs/splice.c:1070
 do_sendfile+0x3b6/0x9a0 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1316 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0xbd/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88813fd7ad70 of 8 bytes by task 10355 on cpu 0:
 __mark_inode_dirty+0x58/0x7d0 fs/fs-writeback.c:2406
 fat_update_time+0x28e/0x2c0 fs/fat/misc.c:359
 inode_update_time fs/inode.c:1913 [inline]
 touch_atime+0x18c/0x310 fs/inode.c:1986
 file_accessed include/linux/fs.h:2203 [inline]
 filemap_splice_read+0x758/0x810 mm/filemap.c:2986
 vfs_splice_read fs/splice.c:889 [inline]
 splice_direct_to_actor+0x2a2/0x660 fs/splice.c:961
 do_splice_direct+0x104/0x180 fs/splice.c:1070
 do_sendfile+0x3b6/0x9a0 fs/read_write.c:1254
 __do_sys_sendfile64 fs/read_write.c:1316 [inline]
 __se_sys_sendfile64 fs/read_write.c:1308 [inline]
 __x64_sys_sendfile64+0xbd/0x150 fs/read_write.c:1308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000000000 -> 0x0000000000000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10355 Comm: syz-executor.0 Not tainted 6.4.0-syzkaller-01224-g1ef6663a587b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
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