syzbot

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BUG: KCSAN: data-race in delete_from_page_cache_batch / filemap_write_and_wait_range

read-write to 0xffff88811942be60 of 8 bytes by task 16400 on cpu 0:
 page_cache_delete_batch mm/filemap.c:313 [inline]
 delete_from_page_cache_batch+0x4f1/0x6f0 mm/filemap.c:332
 truncate_inode_pages_range+0x1b8/0x690 mm/truncate.c:380
 truncate_inode_pages mm/truncate.c:460 [inline]
 truncate_pagecache+0x53/0x70 mm/truncate.c:769
 fat_write_failed fs/fat/inode.c:217 [inline]
 fat_write_end+0xa5/0x160 fs/fat/inode.c:246
 generic_perform_write+0x312/0x490 mm/filemap.c:4196
 __generic_file_write_iter+0x9e/0x120 mm/filemap.c:4292
 generic_file_write_iter+0x8d/0x2f0 mm/filemap.c:4318
 do_iter_readv_writev+0x4a1/0x540 fs/read_write.c:-1
 vfs_writev+0x2df/0x8b0 fs/read_write.c:1057
 do_pwritev fs/read_write.c:1153 [inline]
 __do_sys_pwritev2 fs/read_write.c:1211 [inline]
 __se_sys_pwritev2+0xfc/0x1c0 fs/read_write.c:1202
 __x64_sys_pwritev2+0x67/0x80 fs/read_write.c:1202
 x64_sys_call+0x2c59/0x3000 arch/x86/include/generated/asm/syscalls_64.h:329
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811942be60 of 8 bytes by task 16403 on cpu 1:
 mapping_needs_writeback mm/filemap.c:641 [inline]
 filemap_write_and_wait_range+0x59/0x340 mm/filemap.c:690
 kiocb_write_and_wait mm/filemap.c:2802 [inline]
 generic_file_read_iter+0x101/0x330 mm/filemap.c:2876
 copy_splice_read+0x43f/0x660 fs/splice.c:363
 do_splice_read fs/splice.c:981 [inline]
 splice_direct_to_actor+0x290/0x680 fs/splice.c:1086
 do_splice_direct_actor fs/splice.c:1204 [inline]
 do_splice_direct+0xda/0x150 fs/splice.c:1230
 do_sendfile+0x380/0x650 fs/read_write.c:1370
 __do_sys_sendfile64 fs/read_write.c:1431 [inline]
 __se_sys_sendfile64 fs/read_write.c:1417 [inline]
 __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1417
 x64_sys_call+0x2bb4/0x3000 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x000000000000000a -> 0x0000000000000009

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 16403 Comm: syz.3.2467 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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