BUG: KCSAN: data-race in n_tty_check_unthrottle / n_tty_receive_buf_common

write to 0xffff88811d2025dc of 4 bytes by task 12388 on cpu 0:
 tty_set_flow_change drivers/tty/tty.h:59 [inline]
 n_tty_check_unthrottle+0xd7/0x1c0 drivers/tty/n_tty.c:280
 n_tty_read+0xf0b/0x11d0 drivers/tty/n_tty.c:2312
 iterate_tty_read drivers/tty/tty_io.c:862 [inline]
 tty_read+0x15b/0x480 drivers/tty/tty_io.c:937
 new_sync_read fs/read_write.c:395 [inline]
 vfs_read+0x5e9/0x6e0 fs/read_write.c:476
 ksys_read+0xeb/0x1b0 fs/read_write.c:619
 __do_sys_read fs/read_write.c:629 [inline]
 __se_sys_read fs/read_write.c:627 [inline]
 __x64_sys_read+0x42/0x50 fs/read_write.c:627
 x64_sys_call+0x27d3/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:1
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:893