[AUTOSEL,4.14,02/67] usb: usbtest: use irqsave() in USB's complete callback
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Message ID 20180907003716.57737-2-alexander.levin@microsoft.com
State New, archived
Headers show
Series
  • [AUTOSEL,4.14,01/67] usb: dwc3: change stream event enable bit back to 13
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Commit Message

Sasha Levin Sept. 7, 2018, 12:37 a.m. UTC
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

[ Upstream commit 6f3fde684d0232e66ada3410f016a58e09a87689 ]

The USB completion callback does not disable interrupts while acquiring
the lock. We want to remove the local_irq_disable() invocation from
__usb_hcd_giveback_urb() and therefore it is required for the callback
handler to disable the interrupts while acquiring the lock.
The callback may be invoked either in IRQ or BH context depending on the
USB host controller.
Use the _irqsave() variant of the locking primitives.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
 drivers/usb/misc/usbtest.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

Comments

Greg Kroah-Hartman Sept. 7, 2018, 5:43 a.m. UTC | #1
On Fri, Sep 07, 2018 at 12:37:22AM +0000, Sasha Levin wrote:
> From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> 
> [ Upstream commit 6f3fde684d0232e66ada3410f016a58e09a87689 ]
> 
> The USB completion callback does not disable interrupts while acquiring
> the lock. We want to remove the local_irq_disable() invocation from
> __usb_hcd_giveback_urb() and therefore it is required for the callback
> handler to disable the interrupts while acquiring the lock.
> The callback may be invoked either in IRQ or BH context depending on the
> USB host controller.
> Use the _irqsave() variant of the locking primitives.
> 
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Acked-by: Alan Stern <stern@rowland.harvard.edu>
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
> ---
>  drivers/usb/misc/usbtest.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)

Again, this can be dropped.

thanks,

greg k-h

Patch
diff mbox series

diff --git a/drivers/usb/misc/usbtest.c b/drivers/usb/misc/usbtest.c
index b3fc602b2e24..fcfc562eea4c 100644
--- a/drivers/usb/misc/usbtest.c
+++ b/drivers/usb/misc/usbtest.c
@@ -1073,11 +1073,12 @@  static void ctrl_complete(struct urb *urb)
 	struct usb_ctrlrequest	*reqp;
 	struct subcase		*subcase;
 	int			status = urb->status;
+	unsigned long		flags;
 
 	reqp = (struct usb_ctrlrequest *)urb->setup_packet;
 	subcase = container_of(reqp, struct subcase, setup);
 
-	spin_lock(&ctx->lock);
+	spin_lock_irqsave(&ctx->lock, flags);
 	ctx->count--;
 	ctx->pending--;
 
@@ -1176,7 +1177,7 @@  static void ctrl_complete(struct urb *urb)
 	/* signal completion when nothing's queued */
 	if (ctx->pending == 0)
 		complete(&ctx->complete);
-	spin_unlock(&ctx->lock);
+	spin_unlock_irqrestore(&ctx->lock, flags);
 }
 
 static int
@@ -1852,8 +1853,9 @@  struct transfer_context {
 static void complicated_callback(struct urb *urb)
 {
 	struct transfer_context	*ctx = urb->context;
+	unsigned long flags;
 
-	spin_lock(&ctx->lock);
+	spin_lock_irqsave(&ctx->lock, flags);
 	ctx->count--;
 
 	ctx->packet_count += urb->number_of_packets;
@@ -1893,7 +1895,7 @@  static void complicated_callback(struct urb *urb)
 		complete(&ctx->done);
 	}
 done:
-	spin_unlock(&ctx->lock);
+	spin_unlock_irqrestore(&ctx->lock, flags);
 }
 
 static struct urb *iso_alloc_urb(