================================================================== BUG: KCSAN: data-race in n_tty_receive_char_inline / n_tty_receive_char_special write to 0xffffc90014cf1018 of 8 bytes by task 14569 on cpu 0: add_echo_byte drivers/tty/n_tty.c:845 [inline] echo_char drivers/tty/n_tty.c:948 [inline] eraser drivers/tty/n_tty.c:1043 [inline] n_tty_receive_char_special+0x1156/0x3a70 drivers/tty/n_tty.c:1316 n_tty_receive_buf_standard drivers/tty/n_tty.c:1584 [inline] __receive_buf drivers/tty/n_tty.c:1646 [inline] n_tty_receive_buf_common+0x196c/0x1e70 drivers/tty/n_tty.c:1742 n_tty_receive_buf+0x2b/0x40 drivers/tty/n_tty.c:1771 tiocsti drivers/tty/tty_io.c:2196 [inline] tty_ioctl+0x8e3/0xfd0 drivers/tty/tty_io.c:2572 vfs_ioctl fs/ioctl.c:48 [inline] ksys_ioctl fs/ioctl.c:753 [inline] __do_sys_ioctl fs/ioctl.c:762 [inline] __se_sys_ioctl+0xc9/0x130 fs/ioctl.c:760 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:760 do_syscall_64+0x51/0xb0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffffc90014cf1018 of 8 bytes by task 23940 on cpu 1: add_echo_byte drivers/tty/n_tty.c:845 [inline] echo_char drivers/tty/n_tty.c:948 [inline] n_tty_receive_char_inline+0x43d/0x680 drivers/tty/n_tty.c:1420 n_tty_receive_buf_standard drivers/tty/n_tty.c:1583 [inline] __receive_buf drivers/tty/n_tty.c:1646 [inline] n_tty_receive_buf_common+0x18fa/0x1e70 drivers/tty/n_tty.c:1742 n_tty_receive_buf2+0x2e/0x40 drivers/tty/n_tty.c:1777 tty_ldisc_receive_buf+0x61/0xf0 drivers/tty/tty_buffer.c:461 tty_port_default_receive_buf+0x54/0x80 drivers/tty/tty_port.c:38 receive_buf drivers/tty/tty_buffer.c:481 [inline] flush_to_ldisc+0x1b5/0x2b0 drivers/tty/tty_buffer.c:533 process_one_work+0x3e1/0x9a0 kernel/workqueue.c:2269 worker_thread+0x665/0xbe0 kernel/workqueue.c:2415 kthread+0x20d/0x230 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 23940 Comm: kworker/u4:4 Not tainted 5.8.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound flush_to_ldisc ==================================================================