EXT4-fs: Ignoring removed nomblk_io_submit option
EXT4-fs: Ignoring removed nobh option
EXT4-fs (loop1): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback.
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BUG: KCSAN: data-race in page_cache_sync_ra / page_cache_sync_ra

write to 0xffff88810881fe10 of 8 bytes by task 6532 on cpu 1:
 page_cache_sync_ra+0x434/0x6c0 mm/readahead.c:584
 filemap_get_pages+0x2d0/0x1150 mm/filemap.c:2603
 filemap_splice_read+0x3a9/0x740 mm/filemap.c:2991
 ext4_file_splice_read+0x8f/0xb0 fs/ext4/file.c:158
 do_splice_read fs/splice.c:982 [inline]
 splice_direct_to_actor+0x26c/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

write to 0xffff88810881fe10 of 8 bytes by task 6528 on cpu 0:
 page_cache_sync_ra+0x434/0x6c0 mm/readahead.c:584
 filemap_get_pages+0x2d0/0x1150 mm/filemap.c:2603
 filemap_splice_read+0x3a9/0x740 mm/filemap.c:2991
 ext4_file_splice_read+0x8f/0xb0 fs/ext4/file.c:158
 do_splice_read fs/splice.c:982 [inline]
 splice_direct_to_actor+0x26c/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: 0x0000000000000005 -> 0x0000000000000006

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 6528 Comm: syz.1.1058 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
==================================================================
EXT4-fs error (device loop1): ext4_mb_mark_diskspace_used:4183: comm syz.1.1058: Allocating blocks 1-17 which overlap fs metadata