syzbot

==================================================================
BUG: KCSAN: data-race in dio_bio_end_io / dio_new_bio

read-write to 0xffff88811896d958 of 8 bytes by interrupt on cpu 0:
 dio_bio_end_io+0x53/0xd0 fs/direct-io.c:387
 bio_endio+0x369/0x410 block/bio.c:1548
 blk_update_request+0x368/0x870 block/blk-mq.c:983
 blk_mq_end_request+0x26/0x50 block/blk-mq.c:1145
 lo_complete_rq+0xce/0x180 drivers/block/loop.c:395
 blk_complete_reqs block/blk-mq.c:1220 [inline]
 blk_done_softirq+0x74/0xb0 block/blk-mq.c:1225
 handle_softirqs+0xbf/0x280 kernel/softirq.c:561
 run_ksoftirqd+0x1c/0x30 kernel/softirq.c:950
 smpboot_thread_fn+0x31c/0x4c0 kernel/smpboot.c:164
 kthread+0x4ae/0x520 kernel/kthread.c:464
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff88811896d958 of 8 bytes by task 8269 on cpu 1:
 dio_bio_reap fs/direct-io.c:550 [inline]
 dio_new_bio+0x249/0x460 fs/direct-io.c:669
 dio_send_cur_page+0x1f2/0x7a0 fs/direct-io.c:750
 submit_page_section+0x1a3/0x5b0 fs/direct-io.c:815
 do_direct_IO fs/direct-io.c:1030 [inline]
 __blockdev_direct_IO+0x1375/0x1ed0 fs/direct-io.c:1243
 blockdev_direct_IO include/linux/fs.h:3414 [inline]
 fat_direct_IO+0x10a/0x1d0 fs/fat/inode.c:281
 generic_file_read_iter+0x227/0x330 mm/filemap.c:2870
 copy_splice_read+0x390/0x5d0 fs/splice.c:363
 do_splice_read fs/splice.c:978 [inline]
 splice_direct_to_actor+0x28e/0x680 fs/splice.c:1083
 do_splice_direct_actor fs/splice.c:1201 [inline]
 do_splice_direct+0xd9/0x150 fs/splice.c:1227
 do_sendfile+0x40a/0x690 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+0x113/0x160 fs/read_write.c:1415
 x64_sys_call+0xfc3/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff88811977ff00 -> 0xffff888108653780

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 8269 Comm: syz.4.1698 Tainted: G        W          6.14.0-syzkaller-01103-g2df0c02dab82 #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
==================================================================