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BUG: KCSAN: data-race in fifo_open / wait_for_partner

write to 0xffff88813b91e36c of 4 bytes by task 18237 on cpu 0:
 fifo_open+0xab/0x6a0 fs/pipe.c:1100
 do_dentry_open+0x52c/0x860 fs/open.c:822
 vfs_open+0x43/0x50 fs/open.c:945
 do_open fs/namei.c:3428 [inline]
 path_openat+0x17c3/0x1ec0 fs/namei.c:3561
 do_filp_open+0x105/0x220 fs/namei.c:3588
 do_sys_openat2+0xb5/0x2b0 fs/open.c:1200
 do_sys_open fs/open.c:1216 [inline]
 __do_sys_creat fs/open.c:1290 [inline]
 __se_sys_creat fs/open.c:1284 [inline]
 __x64_sys_creat+0x62/0x80 fs/open.c:1284
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88813b91e36c of 4 bytes by task 18240 on cpu 1:
 pipe_unlock fs/pipe.c:95 [inline]
 wait_for_partner+0x98/0x1d0 fs/pipe.c:1074
 fifo_open+0x555/0x6a0 fs/pipe.c:1165
 do_dentry_open+0x52c/0x860 fs/open.c:822
 vfs_open+0x43/0x50 fs/open.c:945
 do_open fs/namei.c:3428 [inline]
 path_openat+0x17c3/0x1ec0 fs/namei.c:3561
 do_filp_open+0x105/0x220 fs/namei.c:3588
 file_open_name+0xf2/0x120 fs/open.c:1145
 acct_on kernel/acct.c:207 [inline]
 __do_sys_acct kernel/acct.c:286 [inline]
 __se_sys_acct+0xe7/0x410 kernel/acct.c:273
 __x64_sys_acct+0x1b/0x20 kernel/acct.c:273
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000001 -> 0x00000002

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 18240 Comm: syz-executor.4 Not tainted 5.15.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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