==================================================================
BUG: KCSAN: data-race in do_select / pollwake

read to 0xffffc9000b0b7a70 of 4 bytes by task 29874 on cpu 1:
 poll_schedule_timeout fs/select.c:243 [inline]
 do_select+0xea9/0xf90 fs/select.c:607
 core_sys_select+0x361/0x520 fs/select.c:681
 kern_select fs/select.c:722 [inline]
 __do_sys_select fs/select.c:729 [inline]
 __se_sys_select+0x1c7/0x200 fs/select.c:726
 __x64_sys_select+0x67/0x80 fs/select.c:726
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

write to 0xffffc9000b0b7a70 of 4 bytes by task 29897 on cpu 0:
 __pollwake fs/select.c:198 [inline]
 pollwake+0xbe/0x110 fs/select.c:218
 __wake_up_common kernel/sched/wait.c:89 [inline]
 __wake_up_common_lock kernel/sched/wait.c:106 [inline]
 __wake_up+0x64/0xa0 kernel/sched/wait.c:127
 n_tty_set_termios+0x82b/0x840 drivers/tty/n_tty.c:1870
 tty_set_termios+0x843/0x8a0 drivers/tty/tty_ioctl.c:352
 set_termios+0x355/0x4c0 drivers/tty/tty_ioctl.c:520
 tty_mode_ioctl+0x3e1/0x590
 n_tty_ioctl_helper+0x8d/0x240 drivers/tty/tty_ioctl.c:986
 n_tty_ioctl+0xfd/0x200 drivers/tty/n_tty.c:2511
 tty_ioctl+0x875/0xbc0 drivers/tty/tty_io.c:2789
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xcf/0x140 fs/ioctl.c:857
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 29897 Comm: syz-executor.0 Not tainted 6.7.0-rc1-syzkaller-00125-g7475e51b8796 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================