From: Paul Fulghum <paulkf@microgate.com>
To: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
Subject: [PATCH] serial receive lockup fix
Date: Fri, 08 Oct 2004 13:20:56 -0500 [thread overview]
Message-ID: <1097259655.1475.3.camel@deimos.microgate.com> (raw)
Fix lockup caused by serial driver not clearing
receive interrupt if flip buffer becomes full.
Signed-off-by: Paul Fulghum <paulkf@microgate.com>
--- a/drivers/char/serial.c 2004-09-29 09:08:35.000000000 -0500
+++ b/drivers/char/serial.c 2004-09-29 09:09:07.000000000 -0500
@@ -573,8 +573,19 @@
do {
if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
tty->flip.tqueue.routine((void *) tty);
- if (tty->flip.count >= TTY_FLIPBUF_SIZE)
+ if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
+ /* no room in flip buffer, discard rx FIFO contents to clear IRQ
+ * *FIXME* Hardware with auto flow control
+ * would benefit from leaving the data in the FIFO and
+ * disabling the rx IRQ until space becomes available.
+ */
+ do {
+ serial_inp(info, UART_RX);
+ icount->overrun++;
+ *status = serial_inp(info, UART_LSR);
+ } while ((*status & UART_LSR_DR) && (max_count-- > 0));
return; // if TTY_DONT_FLIP is set
+ }
}
ch = serial_inp(info, UART_RX);
*tty->flip.char_buf_ptr = ch;
reply other threads:[~2004-10-08 19:13 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1097259655.1475.3.camel@deimos.microgate.com \
--to=paulkf@microgate.com \
--cc=linux-kernel@vger.kernel.org \
--cc=marcelo.tosatti@cyclades.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Powered by JetHome