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BUG: KCSAN: data-race in atime_needs_update / touch_atime

write to 0xffff88810524fb10 of 4 bytes by task 25588 on cpu 0:
 inode_set_atime_to_ts include/linux/fs.h:1625 [inline]
 inode_update_atime fs/inode.c:2095 [inline]
 inode_update_time fs/inode.c:2153 [inline]
 generic_update_time fs/inode.c:2186 [inline]
 touch_atime+0x1d7/0x330 fs/inode.c:2264
 file_accessed include/linux/fs.h:2263 [inline]
 shmem_file_splice_read+0x5b1/0x600 mm/shmem.c:3678
 do_splice_read fs/splice.c:982 [inline]
 splice_direct_to_actor+0x26e/0x670 fs/splice.c:1086
 do_splice_direct_actor fs/splice.c:1204 [inline]
 do_splice_direct+0x119/0x1a0 fs/splice.c:1230
 do_sendfile+0x382/0x650 fs/read_write.c:1372
 __do_sys_sendfile64 fs/read_write.c:1433 [inline]
 __se_sys_sendfile64 fs/read_write.c:1419 [inline]
 __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1419
 x64_sys_call+0x2dc4/0x3020 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88810524fb10 of 4 bytes by task 25593 on cpu 1:
 atime_needs_update+0x25f/0x3e0 fs/inode.c:-1
 touch_atime+0x4a/0x330 fs/inode.c:2244
 file_accessed include/linux/fs.h:2263 [inline]
 shmem_file_splice_read+0x5b1/0x600 mm/shmem.c:3678
 do_splice_read fs/splice.c:982 [inline]
 splice_direct_to_actor+0x26e/0x670 fs/splice.c:1086
 do_splice_direct_actor fs/splice.c:1204 [inline]
 do_splice_direct+0x119/0x1a0 fs/splice.c:1230
 do_sendfile+0x382/0x650 fs/read_write.c:1372
 __do_sys_sendfile64 fs/read_write.c:1433 [inline]
 __se_sys_sendfile64 fs/read_write.c:1419 [inline]
 __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1419
 x64_sys_call+0x2dc4/0x3020 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x15978330 -> 0x163019b0

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 25593 Comm: syz.3.14661 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
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