From d7cdbdd024d978b9002a20223cc384d11a0a03ea Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Mon, 25 Jun 2018 00:08:44 +0200 Subject: [PATCH] usb: ldusb: use irqsave() in USB's complete callback 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. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Greg Kroah-Hartman --- drivers/usb/misc/ldusb.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/usb/misc/ldusb.c b/drivers/usb/misc/ldusb.c index c2e255f..006762b 100644 --- a/drivers/usb/misc/ldusb.c +++ b/drivers/usb/misc/ldusb.c @@ -225,6 +225,7 @@ static void ld_usb_interrupt_in_callback(struct urb *urb) size_t *actual_buffer; unsigned int next_ring_head; int status = urb->status; + unsigned long flags; int retval; if (status) { @@ -236,12 +237,12 @@ static void ld_usb_interrupt_in_callback(struct urb *urb) dev_dbg(&dev->intf->dev, "%s: nonzero status received: %d\n", __func__, status); - spin_lock(&dev->rbsl); + spin_lock_irqsave(&dev->rbsl, flags); goto resubmit; /* maybe we can recover */ } } - spin_lock(&dev->rbsl); + spin_lock_irqsave(&dev->rbsl, flags); if (urb->actual_length > 0) { next_ring_head = (dev->ring_head+1) % ring_buffer_size; if (next_ring_head != dev->ring_tail) { @@ -270,7 +271,7 @@ resubmit: dev->buffer_overflow = 1; } } - spin_unlock(&dev->rbsl); + spin_unlock_irqrestore(&dev->rbsl, flags); exit: dev->interrupt_in_done = 1; wake_up_interruptible(&dev->read_wait); -- 2.7.4