syzbot

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BUG: KCSAN: data-race in poll_schedule_timeout.constprop.0 / pollwake

write to 0xffffc90004073c10 of 4 bytes by task 28010 on cpu 0:
 __pollwake fs/select.c:197 [inline]
 pollwake+0xe3/0x140 fs/select.c:217
 __wake_up_common+0x7b/0x180 kernel/sched/wait.c:93
 __wake_up_common_lock+0x77/0xb0 kernel/sched/wait.c:123
 __wake_up+0xe/0x10 kernel/sched/wait.c:142
 unix_dgram_peer_wake_relay+0xdf/0x170 net/unix/af_unix.c:369
 __wake_up_common+0x7b/0x180 kernel/sched/wait.c:93
 __wake_up_common_lock+0x77/0xb0 kernel/sched/wait.c:123
 __wake_up_sync_key+0x19/0x20 kernel/sched/wait.c:196
 unix_dgram_recvmsg+0x2c9/0xba0 net/unix/af_unix.c:2074
 sock_recvmsg_nosec+0x5c/0x70 net/socket.c:871
 ___sys_recvmsg+0x1a0/0x3e0 net/socket.c:2480
 do_recvmmsg+0x19a/0x5c0 net/socket.c:2601
 __sys_recvmmsg+0x1ef/0x200 net/socket.c:2680
 __do_sys_recvmmsg net/socket.c:2703 [inline]
 __se_sys_recvmmsg net/socket.c:2696 [inline]
 __x64_sys_recvmmsg+0x89/0xb0 net/socket.c:2696
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffffc90004073c10 of 4 bytes by task 28015 on cpu 1:
 poll_schedule_timeout.constprop.0+0x50/0xc0 fs/select.c:242
 do_poll fs/select.c:951 [inline]
 do_sys_poll+0x66d/0x990 fs/select.c:1001
 __do_sys_ppoll fs/select.c:1101 [inline]
 __se_sys_ppoll fs/select.c:1081 [inline]
 __x64_sys_ppoll+0x161/0x1a0 fs/select.c:1081
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 28015 Comm: syz-executor.4 Not tainted 5.4.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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