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BUG: KCSAN: data-race in fifo_open / wait_for_partner

read-write to 0xffff88811b90aa64 of 4 bytes by task 10563 on cpu 0:
 fifo_open+0x89/0x5b0 fs/pipe.c:1213
 do_dentry_open+0x49f/0xa60 fs/open.c:996
 vfs_open+0x37/0x1e0 fs/open.c:1101
 do_open fs/namei.c:4837 [inline]
 path_openat+0xc01/0x10d0 fs/namei.c:5000
 do_file_open+0x16c/0x290 fs/namei.c:5029
 file_open_name+0xfa/0x120 fs/open.c:1375
 acct_on kernel/acct.c:229 [inline]
 __do_sys_acct kernel/acct.c:302 [inline]
 __se_sys_acct+0x8c/0x500 kernel/acct.c:293
 __x64_sys_acct+0x1f/0x30 kernel/acct.c:293
 x64_sys_call+0x1461/0x2550 arch/x86/include/generated/asm/syscalls_64.h:164
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811b90aa64 of 4 bytes by task 10554 on cpu 1:
 pipe_lock fs/pipe.c:90 [inline]
 wait_for_partner+0x109/0x1d0 fs/pipe.c:1190
 fifo_open+0x491/0x5b0 fs/pipe.c:1278
 do_dentry_open+0x49f/0xa60 fs/open.c:996
 vfs_open+0x37/0x1e0 fs/open.c:1101
 do_open fs/namei.c:4837 [inline]
 path_openat+0xc01/0x10d0 fs/namei.c:5000
 do_file_open+0x16c/0x290 fs/namei.c:5029
 do_sys_openat2+0xa0/0x130 fs/open.c:1417
 do_sys_open fs/open.c:1423 [inline]
 __do_sys_creat fs/open.c:1501 [inline]
 __se_sys_creat fs/open.c:1495 [inline]
 __x64_sys_creat+0x65/0x90 fs/open.c:1495
 x64_sys_call+0xea6/0x2550 arch/x86/include/generated/asm/syscalls_64.h:86
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000001 -> 0x00000002

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 10554 Comm: syz.1.2113 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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