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BUG: KCSAN: data-race in __mark_inode_dirty / __writeback_single_inode

read-write to 0xffff888116fd7c38 of 4 bytes by task 5442 on cpu 0:
 __writeback_single_inode+0x1f4/0x850 fs/fs-writeback.c:1716
 writeback_single_inode+0x16c/0x3f0 fs/fs-writeback.c:1801
 sync_inode_metadata+0x5c/0x90 fs/fs-writeback.c:2871
 generic_buffers_fsync_noflush+0xd8/0x120 fs/buffer.c:610
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x1ff/0x6c0 fs/ext4/fsync.c:151
 vfs_fsync_range+0x116/0x130 fs/sync.c:187
 generic_write_sync include/linux/fs.h:2920 [inline]
 ext4_buffered_write_iter+0x326/0x370 fs/ext4/file.c:305
 ext4_file_write_iter+0x383/0xf20
 iter_file_splice_write+0x5f1/0x980 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x160/0x2c0 fs/splice.c:1164
 splice_direct_to_actor+0x302/0x670 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x398/0x660 fs/read_write.c:1363
 __do_sys_sendfile64 fs/read_write.c:1424 [inline]
 __se_sys_sendfile64 fs/read_write.c:1410 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1410
 x64_sys_call+0xfbd/0x2dc0 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 0xffff888116fd7c38 of 4 bytes by task 5468 on cpu 1:
 __mark_inode_dirty+0x198/0x7e0 fs/fs-writeback.c:2537
 mark_buffer_dirty+0x149/0x230 fs/buffer.c:1199
 __ext4_block_zero_page_range fs/ext4/inode.c:3760 [inline]
 ext4_block_zero_page_range+0x484/0x590 fs/ext4/inode.c:3798
 ext4_zero_partial_blocks+0xe3/0x190 fs/ext4/inode.c:3850
 ext4_alloc_file_blocks+0x4bd/0x730 fs/ext4/extents.c:4546
 ext4_fallocate+0x748/0x1170 fs/ext4/extents.c:4822
 vfs_fallocate+0x368/0x3b0 fs/open.c:327
 ksys_fallocate fs/open.c:351 [inline]
 __do_sys_fallocate fs/open.c:356 [inline]
 __se_sys_fallocate fs/open.c:354 [inline]
 __x64_sys_fallocate+0x78/0xc0 fs/open.c:354
 x64_sys_call+0x43c/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:286
 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: 0x0000003a -> 0x00000022

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 5468 Comm: syz.6.495 Not tainted 6.13.0-syzkaller-04541-gdf60eac9efe8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
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