This is a note to let you know that I've just added the patch titled

     Subject: USB: Fix a bug in usb_start_wait_urb

to my gregkh-2.6 tree.  Its filename is

     usb-fix-a-bug-in-usb_start_wait_urb.patch

This tree can be found at 
    http://www.kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/patches/


>From [EMAIL PROTECTED] Tue Jul 24 15:23:27 2007
From: Alan Stern <[EMAIL PROTECTED]>
Date: Tue, 24 Jul 2007 18:23:23 -0400 (EDT)
Subject: USB: Fix a bug in usb_start_wait_urb
To: Greg KH <[EMAIL PROTECTED]>
Cc: Pavel Roskin <[EMAIL PROTECTED]>,  USB development list 
<linux-usb-devel@lists.sourceforge.net>
Message-ID: <[EMAIL PROTECTED]>


This patch (as941) fixes a bug recently added to the USB synchronous
API.  The status of a completed URB must be preserved separately
across a completion callback.  Also, the actual_length value isn't
available until after the URB has fully completed.

Signed-off-by: Alan Stern <[EMAIL PROTECTED]>
Signed-off-by: Greg Kroah-Hartman <[EMAIL PROTECTED]>

---
 drivers/usb/core/message.c |   26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -18,9 +18,17 @@
 #include "hcd.h"       /* for usbcore internals */
 #include "usb.h"
 
+struct api_context {
+       struct completion       done;
+       int                     status;
+};
+
 static void usb_api_blocking_completion(struct urb *urb)
 {
-       complete((struct completion *)urb->context);
+       struct api_context *ctx = urb->context;
+
+       ctx->status = urb->status;
+       complete(&ctx->done);
 }
 
 
@@ -32,20 +40,21 @@ static void usb_api_blocking_completion(
  */
 static int usb_start_wait_urb(struct urb *urb, int timeout, int *actual_length)
 { 
-       struct completion done;
+       struct api_context ctx;
        unsigned long expire;
        int retval;
-       int status = urb->status;
 
-       init_completion(&done);         
-       urb->context = &done;
+       init_completion(&ctx.done);
+       urb->context = &ctx;
        urb->actual_length = 0;
        retval = usb_submit_urb(urb, GFP_NOIO);
        if (unlikely(retval))
                goto out;
 
        expire = timeout ? msecs_to_jiffies(timeout) : MAX_SCHEDULE_TIMEOUT;
-       if (!wait_for_completion_timeout(&done, expire)) {
+       if (!wait_for_completion_timeout(&ctx.done, expire)) {
+               usb_kill_urb(urb);
+               retval = (ctx.status == -ENOENT ? -ETIMEDOUT : ctx.status);
 
                dev_dbg(&urb->dev->dev,
                        "%s timed out on ep%d%s len=%d/%d\n",
@@ -54,11 +63,8 @@ static int usb_start_wait_urb(struct urb
                        usb_pipein(urb->pipe) ? "in" : "out",
                        urb->actual_length,
                        urb->transfer_buffer_length);
-
-               usb_kill_urb(urb);
-               retval = status == -ENOENT ? -ETIMEDOUT : status;
        } else
-               retval = status;
+               retval = ctx.status;
 out:
        if (actual_length)
                *actual_length = urb->actual_length;


Patches currently in gregkh-2.6 which might be from [EMAIL PROTECTED] are

usb/usb-fix-a-bug-in-usb_start_wait_urb.patch
usb/usb-fix-bug-sleeping-function-called-from-invalid-context-at-home-jeremy-hg-xen-paravirt-linux-drivers-usb-core-urb.c-524-in_atomic-1-irqs_disabled-0.patch
usb/usb-nikon-d50-is-an-unusual-device.patch
usb/usb-don-t-let-usb-storage-steal-blackberry-pearl.patch

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