From: Denis Joseph Barrow <D.Barow-x9gZzRpC1QbQT0dZR+AlfA@public•gmane.org>
To: Linux USB kernel mailing list
<linux-usb-u79uwXL29TY76Z2rM5mHXA@public•gmane.org>,
Linux netdev Mailing list
<netdev-u79uwXL29TY76Z2rM5mHXA@public•gmane.org>
Subject: [PATCH] hso_spinlockfix.patch
Date: Wed, 14 Jan 2009 10:54:51 +0100 [thread overview]
Message-ID: <496DB66B.4070306@option.com> (raw)
[-- Attachment #1: Type: text/plain, Size: 1412 bytes --]
Hi,
This is a really important fix it fixes a consistent kernel deadlock
when the hso driver starts going. It's against 2.6.29-rc1, 2.6.29-rc6
worked fine.
This patch obviously wasn't tested & I neither I or Filip was subscribed to the tty mailing
list to catch it.
Even with this patch the driver is still broken.
opening the serial port on the driver a second time causes a -EIO,
I've yet to figure out what but it is not returned from hso_serial_open
but a parent function.
This patch fixes a double grabbing of a spinlock all
functions which call put_rxbuf_data already have serial->serial_lock grabbed.
Signed-off-by: Denis Joseph Barrow <D.Barow-x9gZzRpC1QbQT0dZR+AlfA@public•gmane.org>
Index: linux-2.6/drivers/net/usb/hso.c
===================================================================
--- linux-2.6.orig/drivers/net/usb/hso.c 2009-01-13 17:39:15.000000000 +0100
+++ linux-2.6/drivers/net/usb/hso.c 2009-01-13 17:40:42.000000000 +0100
@@ -2043,9 +2043,7 @@
return -2;
}
- spin_lock(&serial->serial_lock);
tty = tty_kref_get(serial->tty);
- spin_unlock(&serial->serial_lock);
/* Push data to tty */
if (tty) {
--
best regards,
D.J. Barrow
Linux Kernel Developer
Option NV, Gaston Geenslaan 14, 3001 Leuven, Belgium
T: +32 16 311 621
F: +32 16 207 164
d.barow-x9gZzRpC1QbQT0dZR+AlfA@public•gmane.org
www.option.com
Disclaimer:
http://www.option.com/company/disclaimer.shtml
[-- Attachment #2: hso_spinlockfix.patch --]
[-- Type: text/x-diff, Size: 661 bytes --]
This patch fixes a double grabbing of a spinlock all
functions which call put_rxbuf_data already have serial->serial_lock grabbed.
Signed-off-by: Denis Joseph Barrow <D.Barow-x9gZzRpC1QbQT0dZR+AlfA@public•gmane.org>
Index: linux-2.6/drivers/net/usb/hso.c
===================================================================
--- linux-2.6.orig/drivers/net/usb/hso.c 2009-01-13 17:39:15.000000000 +0100
+++ linux-2.6/drivers/net/usb/hso.c 2009-01-13 17:40:42.000000000 +0100
@@ -2043,9 +2043,7 @@
return -2;
}
- spin_lock(&serial->serial_lock);
tty = tty_kref_get(serial->tty);
- spin_unlock(&serial->serial_lock);
/* Push data to tty */
if (tty) {
next reply other threads:[~2009-01-14 9:54 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-01-14 9:54 Denis Joseph Barrow [this message]
2009-01-14 10:08 ` [PATCH] hso_spinlockfix.patch David Miller
2009-01-14 10:14 ` Denis Joseph Barrow
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