From 273925c777420585af1ca18548b73e730043576e Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Mon, 10 Sep 2018 11:19:58 +0200 Subject: [PATCH] media: em28xx-audio: 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. Cc: Mauro Carvalho Chehab Signed-off-by: Sebastian Andrzej Siewior Acked-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/usb/em28xx/em28xx-audio.c | 5 +++-- drivers/media/usb/em28xx/em28xx-core.c | 5 +++-- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/media/usb/em28xx/em28xx-audio.c b/drivers/media/usb/em28xx/em28xx-audio.c index 8e799ae..67481fc 100644 --- a/drivers/media/usb/em28xx/em28xx-audio.c +++ b/drivers/media/usb/em28xx/em28xx-audio.c @@ -116,6 +116,7 @@ static void em28xx_audio_isocirq(struct urb *urb) stride = runtime->frame_bits >> 3; for (i = 0; i < urb->number_of_packets; i++) { + unsigned long flags; int length = urb->iso_frame_desc[i].actual_length / stride; cp = (unsigned char *)urb->transfer_buffer + @@ -137,7 +138,7 @@ static void em28xx_audio_isocirq(struct urb *urb) length * stride); } - snd_pcm_stream_lock(substream); + snd_pcm_stream_lock_irqsave(substream, flags); dev->adev.hwptr_done_capture += length; if (dev->adev.hwptr_done_capture >= @@ -153,7 +154,7 @@ static void em28xx_audio_isocirq(struct urb *urb) period_elapsed = 1; } - snd_pcm_stream_unlock(substream); + snd_pcm_stream_unlock_irqrestore(substream, flags); } if (period_elapsed) snd_pcm_period_elapsed(substream); diff --git a/drivers/media/usb/em28xx/em28xx-core.c b/drivers/media/usb/em28xx/em28xx-core.c index 5657f87..2b8c84a 100644 --- a/drivers/media/usb/em28xx/em28xx-core.c +++ b/drivers/media/usb/em28xx/em28xx-core.c @@ -777,6 +777,7 @@ EXPORT_SYMBOL_GPL(em28xx_set_mode); static void em28xx_irq_callback(struct urb *urb) { struct em28xx *dev = urb->context; + unsigned long flags; int i; switch (urb->status) { @@ -793,9 +794,9 @@ static void em28xx_irq_callback(struct urb *urb) } /* Copy data from URB */ - spin_lock(&dev->slock); + spin_lock_irqsave(&dev->slock, flags); dev->usb_ctl.urb_data_copy(dev, urb); - spin_unlock(&dev->slock); + spin_unlock_irqrestore(&dev->slock, flags); /* Reset urb buffers */ for (i = 0; i < urb->number_of_packets; i++) { -- 2.7.4