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BUG: KCSAN: data-race in __mark_inode_dirty / writeback_single_inode

write to 0xffff88813659c770 of 8 bytes by task 5149 on cpu 0:
 writeback_single_inode+0x109/0x4f0 fs/fs-writeback.c:1705
 sync_inode_metadata+0x52/0x70 fs/fs-writeback.c:2743
 __generic_file_fsync+0xf5/0x140 fs/libfs.c:1126
 fat_file_fsync+0x48/0x100 fs/fat/file.c:190
 vfs_fsync_range+0x107/0x120 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2731 [inline]
 generic_file_write_iter+0x103/0x130 mm/filemap.c:3934
 do_iter_readv_writev+0x27b/0x300
 do_iter_write+0x16f/0x5c0 fs/read_write.c:868
 vfs_iter_write+0x4c/0x70 fs/read_write.c:909
 iter_file_splice_write+0x44a/0x7c0 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x660 fs/splice.c:891
 do_splice_direct+0xfb/0x180 fs/splice.c:979
 do_sendfile+0x3ad/0x900 fs/read_write.c:1262
 __do_sys_sendfile64 fs/read_write.c:1321 [inline]
 __se_sys_sendfile64 fs/read_write.c:1313 [inline]
 __x64_sys_sendfile64+0xb9/0x150 fs/read_write.c:1313
 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+0x46/0xb0

read to 0xffff88813659c770 of 8 bytes by task 5152 on cpu 1:
 __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:2386 [inline]
 filemap_read+0x137e/0x1400 mm/filemap.c:2747
 generic_file_read_iter+0x72/0x320 mm/filemap.c:2825
 call_read_iter include/linux/fs.h:2052 [inline]
 generic_file_splice_read+0x1de/0x2c0 fs/splice.c:311
 do_splice_to fs/splice.c:796 [inline]
 splice_direct_to_actor+0x2ac/0x660 fs/splice.c:870
 do_splice_direct+0xfb/0x180 fs/splice.c:979
 do_sendfile+0x3ad/0x900 fs/read_write.c:1262
 __do_sys_sendfile64 fs/read_write.c:1327 [inline]
 __se_sys_sendfile64 fs/read_write.c:1313 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1313
 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+0x46/0xb0

value changed: 0x0000000000000007 -> 0x0000000000000080

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5152 Comm: syz-executor.2 Not tainted 5.19.0-rc2-syzkaller-00117-g47700948a4ab-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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==================================================================
BUG: KCSAN: data-race in filemap_fdatawrite_wbc / xas_set_mark

write to 0xffff88813659c85c of 4 bytes by task 5149 on cpu 0:
 xa_mark_set lib/xarray.c:69 [inline]
 xas_set_mark+0x11e/0x130 lib/xarray.c:894
 __folio_start_writeback+0x2bf/0x5d0 mm/page-writeback.c:2949
 set_page_writeback+0x3d/0xe0 mm/folio-compat.c:78
 __block_write_full_page+0x4f7/0xb00 fs/buffer.c:1802
 block_write_full_page+0xda/0x100
 fat_writepage+0x20/0x30 fs/fat/inode.c:199
 __mpage_writepage+0xb73/0x10d0 fs/mpage.c:626
 write_cache_pages+0x443/0xa30 mm/page-writeback.c:2334
 mpage_writepages+0x7b/0x100 fs/mpage.c:678
 fat_writepages+0x20/0x30 fs/fat/inode.c:205
 do_writepages+0x1db/0x350 mm/page-writeback.c:2443
 filemap_fdatawrite_wbc+0xd6/0xf0 mm/filemap.c:388
 __filemap_fdatawrite_range mm/filemap.c:421 [inline]
 file_write_and_wait_range+0xd6/0x170 mm/filemap.c:779
 __generic_file_fsync+0x48/0x140 fs/libfs.c:1115
 fat_file_fsync+0x48/0x100 fs/fat/file.c:190
 vfs_fsync_range+0x107/0x120 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2731 [inline]
 generic_file_write_iter+0x103/0x130 mm/filemap.c:3934
 do_iter_readv_writev+0x27b/0x300
 do_iter_write+0x16f/0x5c0 fs/read_write.c:868
 vfs_iter_write+0x4c/0x70 fs/read_write.c:909
 iter_file_splice_write+0x44a/0x7c0 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x660 fs/splice.c:891
 do_splice_direct+0xfb/0x180 fs/splice.c:979
 do_sendfile+0x3ad/0x900 fs/read_write.c:1262
 __do_sys_sendfile64 fs/read_write.c:1321 [inline]
 __se_sys_sendfile64 fs/read_write.c:1313 [inline]
 __x64_sys_sendfile64+0xb9/0x150 fs/read_write.c:1313
 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+0x46/0xb0

read to 0xffff88813659c85c of 4 bytes by task 5152 on cpu 1:
 xa_marked include/linux/xarray.h:419 [inline]
 mapping_tagged include/linux/fs.h:446 [inline]
 filemap_fdatawrite_wbc+0x57/0xf0 mm/filemap.c:384
 __filemap_fdatawrite_range mm/filemap.c:421 [inline]
 filemap_write_and_wait_range+0xbf/0x2e0 mm/filemap.c:673
 generic_file_direct_write+0xb7/0x400 mm/filemap.c:3670
 __generic_file_write_iter+0x11f/0x280 mm/filemap.c:3854
 generic_file_write_iter+0x75/0x130 mm/filemap.c:3930
 do_iter_readv_writev+0x27b/0x300
 do_iter_write+0x16f/0x5c0 fs/read_write.c:868
 vfs_iter_write+0x4c/0x70 fs/read_write.c:909
 iter_file_splice_write+0x44a/0x7c0 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x660 fs/splice.c:891
 do_splice_direct+0xfb/0x180 fs/splice.c:979
 do_sendfile+0x3ad/0x900 fs/read_write.c:1262
 __do_sys_sendfile64 fs/read_write.c:1327 [inline]
 __se_sys_sendfile64 fs/read_write.c:1313 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1313
 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+0x46/0xb0

value changed: 0x28000021 -> 0x10000021

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5152 Comm: syz-executor.2 Not tainted 5.19.0-rc2-syzkaller-00117-g47700948a4ab-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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