This is a note to let you know that I've just added the patch titled
USB: additional regression fix for device removal
to the 2.6.39-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-additional-regression-fix-for-device-removal.patch
and it can be found in the queue-2.6.39 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.
From ca5c485f55d326d9a23e4badd05890148aa53f74 Mon Sep 17 00:00:00 2001
From: Alan Stern <[email protected]>
Date: Wed, 6 Jul 2011 17:03:45 -0400
Subject: USB: additional regression fix for device removal
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
From: Alan Stern <[email protected]>
commit ca5c485f55d326d9a23e4badd05890148aa53f74 upstream.
Commit e534c5b831c8b8e9f5edee5c8a37753c808b80dc (USB: fix regression
occurring during device removal) didn't go far enough. It failed to
take into account that when a driver claims multiple interfaces, it may
release them all at the same time. As a result, some interfaces can
get released before they are unregistered, and we deadlock trying to
acquire the bandwidth_mutex that we already own.
This patch (asl478) handles this case by setting the "unregistering"
flag on all the interfaces before removing any of them.
Signed-off-by: Alan Stern <[email protected]>
Tested-by: Éric Piel <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
drivers/usb/core/message.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -1147,6 +1147,14 @@ void usb_disable_device(struct usb_devic
* any drivers bound to them (a key side effect)
*/
if (dev->actconfig) {
+ /*
+ * FIXME: In order to avoid self-deadlock involving the
+ * bandwidth_mutex, we have to mark all the interfaces
+ * before unregistering any of them.
+ */
+ for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++)
+ dev->actconfig->interface[i]->unregistering = 1;
+
for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
struct usb_interface *interface;
@@ -1156,7 +1164,6 @@ void usb_disable_device(struct usb_devic
continue;
dev_dbg(&dev->dev, "unregistering interface %s\n",
dev_name(&interface->dev));
- interface->unregistering = 1;
remove_intf_ep_devs(interface);
device_del(&interface->dev);
}
Patches currently in stable-queue which might be from [email protected]
are
queue-2.6.39/usb-additional-regression-fix-for-device-removal.patch
queue-2.6.39/usb-don-t-let-errors-prevent-system-sleep.patch
queue-2.6.39/pm-fix-async-resume-following-suspend-failure.patch
queue-2.6.39/usb-free-bandwidth-when-usb_disable_device-is-called.patch
queue-2.6.39/pm-rename-dev_pm_info.in_suspend-to-is_prepared.patch
queue-2.6.39/usb-don-t-let-the-hub-driver-prevent-system-sleep.patch
queue-2.6.39/usb-fix-regression-occurring-during-device-removal.patch
_______________________________________________
stable mailing list
[email protected]
http://linux.kernel.org/mailman/listinfo/stable
