From 579b9cca2bff170ac4c4487de6e8ebff7906b3a6 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Mon, 25 Jun 2018 00:08:35 +0200 Subject: [PATCH] usb: cdc-wdm: use irqsave() in USB's complete callback MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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: Oliver Neukum Cc: "Bjørn Mork" Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/cdc-wdm.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c index 203bbd378858..bec581fb7c63 100644 --- a/drivers/usb/class/cdc-wdm.c +++ b/drivers/usb/class/cdc-wdm.c @@ -142,10 +142,12 @@ found: static void wdm_out_callback(struct urb *urb) { struct wdm_device *desc; + unsigned long flags; + desc = urb->context; - spin_lock(&desc->iuspin); + spin_lock_irqsave(&desc->iuspin, flags); desc->werr = urb->status; - spin_unlock(&desc->iuspin); + spin_unlock_irqrestore(&desc->iuspin, flags); kfree(desc->outbuf); desc->outbuf = NULL; clear_bit(WDM_IN_USE, &desc->flags); @@ -154,11 +156,12 @@ static void wdm_out_callback(struct urb *urb) static void wdm_in_callback(struct urb *urb) { + unsigned long flags; struct wdm_device *desc = urb->context; int status = urb->status; int length = urb->actual_length; - spin_lock(&desc->iuspin); + spin_lock_irqsave(&desc->iuspin, flags); clear_bit(WDM_RESPONDING, &desc->flags); if (status) { @@ -220,11 +223,12 @@ skip_error: set_bit(WDM_READ, &desc->flags); wake_up(&desc->wait); } - spin_unlock(&desc->iuspin); + spin_unlock_irqrestore(&desc->iuspin, flags); } static void wdm_int_callback(struct urb *urb) { + unsigned long flags; int rv = 0; int responding; int status = urb->status; @@ -284,7 +288,7 @@ static void wdm_int_callback(struct urb *urb) goto exit; } - spin_lock(&desc->iuspin); + spin_lock_irqsave(&desc->iuspin, flags); responding = test_and_set_bit(WDM_RESPONDING, &desc->flags); if (!desc->resp_count++ && !responding && !test_bit(WDM_DISCONNECTING, &desc->flags) @@ -292,7 +296,7 @@ static void wdm_int_callback(struct urb *urb) rv = usb_submit_urb(desc->response, GFP_ATOMIC); dev_dbg(&desc->intf->dev, "submit response URB %d\n", rv); } - spin_unlock(&desc->iuspin); + spin_unlock_irqrestore(&desc->iuspin, flags); if (rv < 0) { clear_bit(WDM_RESPONDING, &desc->flags); if (rv == -EPERM) -- 2.11.0