This is a note to let you know that I've just added the patch titled
USB: cdc-acm: fix break reporting
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-cdc-acm-fix-break-reporting.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 58fc1daa4d2e9789b9ffc880907c961ea7c062cc Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@xxxxxxxxxx>
Date: Wed, 29 Sep 2021 11:09:37 +0200
Subject: USB: cdc-acm: fix break reporting
From: Johan Hovold <johan@xxxxxxxxxx>
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@xxxxxxxxxxxxxxx
Acked-by: Oliver Neukum <oneukum@xxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210929090937.7410-3-johan@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/class/cdc-acm.c | 3 +++
1 file changed, 3 insertions(+)
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -348,6 +348,9 @@ static void acm_ctrl_irq(struct urb *urb
acm->iocount.overrun++;
spin_unlock(&acm->read_lock);
+ if (newctrl & ACM_CTRL_BRK)
+ tty_flip_buffer_push(&acm->port);
+
if (difference)
wake_up_all(&acm->wioctl);
Patches currently in stable-queue which might be from johan@xxxxxxxxxx are
queue-4.4/usb-cdc-acm-fix-break-reporting.patch
queue-4.4/usb-cdc-acm-fix-racy-tty-buffer-accesses.patch
