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BUG: KCSAN: data-race in __mark_inode_dirty / __mark_inode_dirty

write to 0xffff8881069c5c78 of 8 bytes by task 4203 on cpu 0:
 __mark_inode_dirty+0x256/0x7e0 fs/fs-writeback.c:2517
 mark_buffer_dirty+0x165/0x250 fs/buffer.c:1211
 __block_commit_write fs/buffer.c:2200 [inline]
 block_write_end+0x158/0x2e0 fs/buffer.c:2276
 generic_write_end+0x55/0x230 fs/buffer.c:2290
 fat_write_end+0x4e/0x160 fs/fat/inode.c:244
 generic_perform_write+0x276/0x410 mm/filemap.c:4026
 __generic_file_write_iter+0xa1/0x120 mm/filemap.c:4110
 generic_file_write_iter+0x7d/0x1d0 mm/filemap.c:4136
 iter_file_splice_write+0x5e6/0x970 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x16c/0x2c0 fs/splice.c:1164
 splice_direct_to_actor+0x305/0x670 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x3ab/0x960 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
 x64_sys_call+0x2c9f/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881069c5c78 of 8 bytes by task 4204 on cpu 1:
 __mark_inode_dirty+0x58/0x7e0 fs/fs-writeback.c:2468
 fat_update_time+0x1fe/0x210 fs/fat/misc.c:357
 inode_update_time fs/inode.c:1919 [inline]
 touch_atime+0x14f/0x350 fs/inode.c:1992
 file_accessed include/linux/fs.h:2458 [inline]
 filemap_splice_read+0x8b0/0x920 mm/filemap.c:2950
 do_splice_read fs/splice.c:985 [inline]
 splice_direct_to_actor+0x26c/0x670 fs/splice.c:1089
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x3ab/0x960 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
 x64_sys_call+0x2c9f/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000001 -> 0x0000000000000007

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 4204 Comm: syz-executor.4 Not tainted 6.10.0-rc4-syzkaller-00148-g50736169ecc8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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