From: Johan Hovold <johan@kernel.org> stable inclusion from stable-5.10.73 commit feb3fe702a589ccf95ad5c5312db35462ab80733 bugzilla: 182983 https://gitee.com/openeuler/kernel/issues/I4I3M0 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 58fc1daa4d2e9789b9ffc880907c961ea7c062cc upstream. A recent change that started reporting break events forgot to push the event to the line discipline, which meant that a detected break would not be reported until further characters had been receive (the port could even have been closed and reopened in between). Fixes: 08dff274edda ("cdc-acm: fix BREAK rx code path adding necessary calls") Cc: stable@vger.kernel.org Acked-by: Oliver Neukum <oneukum@suse.com> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20210929090937.7410-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- drivers/usb/class/cdc-acm.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 80508daf75ac..7950d5b3af42 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -340,6 +340,9 @@ static void acm_process_notification(struct acm *acm, unsigned char *buf) acm->iocount.overrun++; spin_unlock_irqrestore(&acm->read_lock, flags); + if (newctrl & ACM_CTRL_BRK) + tty_flip_buffer_push(&acm->port); + if (difference) wake_up_all(&acm->wioctl); -- 2.20.1