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BUG: KCSAN: data-race in __filemap_remove_folio / filemap_write_and_wait_range

read-write to 0xffff8881073e5d90 of 8 bytes by task 7180 on cpu 0:
 page_cache_delete mm/filemap.c:146 [inline]
 __filemap_remove_folio+0x1bc/0x2a0 mm/filemap.c:224
 __remove_mapping+0x338/0x460 mm/vmscan.c:813
 remove_mapping+0x22/0x90 mm/vmscan.c:846
 mapping_evict_folio mm/truncate.c:310 [inline]
 mapping_try_invalidate+0x26a/0x3f0 mm/truncate.c:531
 invalidate_mapping_pages+0x27/0x40 mm/truncate.c:573
 ext4_dio_write_iter fs/ext4/file.c:624 [inline]
 ext4_file_write_iter+0xe70/0xf00 fs/ext4/file.c:716
 iter_file_splice_write+0x5ef/0x970 fs/splice.c:738
 do_splice_from fs/splice.c:935 [inline]
 direct_splice_actor+0x156/0x2a0 fs/splice.c:1158
 splice_direct_to_actor+0x312/0x680 fs/splice.c:1102
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0xda/0x150 fs/splice.c:1227
 do_sendfile+0x380/0x640 fs/read_write.c:1368
 __do_sys_sendfile64 fs/read_write.c:1429 [inline]
 __se_sys_sendfile64 fs/read_write.c:1415 [inline]
 __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1415
 x64_sys_call+0xb39/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881073e5d90 of 8 bytes by task 7175 on cpu 1:
 mapping_needs_writeback mm/filemap.c:641 [inline]
 filemap_write_and_wait_range+0x59/0x340 mm/filemap.c:690
 ext4_dio_write_iter fs/ext4/file.c:621 [inline]
 ext4_file_write_iter+0xe04/0xf00 fs/ext4/file.c:716
 iter_file_splice_write+0x5ef/0x970 fs/splice.c:738
 do_splice_from fs/splice.c:935 [inline]
 direct_splice_actor+0x156/0x2a0 fs/splice.c:1158
 splice_direct_to_actor+0x312/0x680 fs/splice.c:1102
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0xda/0x150 fs/splice.c:1227
 do_sendfile+0x380/0x640 fs/read_write.c:1368
 __do_sys_sendfile64 fs/read_write.c:1429 [inline]
 __se_sys_sendfile64 fs/read_write.c:1415 [inline]
 __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1415
 x64_sys_call+0xb39/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000001 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 7175 Comm: syz.1.1408 Not tainted 6.15.0-rc6-syzkaller-00051-g405e6c37c89e #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
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