This is a note to let you know that I've just added the patch titled
ALSA: pcm: Use dma_bytes as size parameter in dma_mmap_coherent()
to the 3.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
alsa-pcm-use-dma_bytes-as-size-parameter-in-dma_mmap_coherent.patch
and it can be found in the queue-3.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 9066ae7ff5d89c0b5daa271e2d573540097a94fa Mon Sep 17 00:00:00 2001
From: Stefan Roese <sr@xxxxxxx>
Date: Mon, 26 Mar 2018 16:10:21 +0200
Subject: ALSA: pcm: Use dma_bytes as size parameter in dma_mmap_coherent()
From: Stefan Roese <sr@xxxxxxx>
commit 9066ae7ff5d89c0b5daa271e2d573540097a94fa upstream.
When trying to use the driver (e.g. aplay *.wav), the 4MiB DMA buffer
will get mmapp'ed in 16KiB chunks. But this fails with the 2nd 16KiB
area, as the page offset is outside of the VMA range (size), which is
currently used as size parameter in snd_pcm_lib_default_mmap(). By
using the DMA buffer size (dma_bytes) instead, the complete DMA buffer
can be mmapp'ed and the issue is fixed.
This issue was detected on an ARM platform (TI AM57xx) using the RME
HDSP MADI PCIe soundcard.
Fixes: 657b1989dacf ("ALSA: pcm - Use dma_mmap_coherent() if available")
Signed-off-by: Stefan Roese <sr@xxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
sound/core/pcm_native.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -3394,7 +3394,7 @@ int snd_pcm_lib_default_mmap(struct snd_
area,
substream->runtime->dma_area,
substream->runtime->dma_addr,
- area->vm_end - area->vm_start);
+ substream->runtime->dma_bytes);
#elif defined(CONFIG_MIPS) && defined(CONFIG_DMA_NONCOHERENT)
if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV &&
!plat_device_is_coherent(substream->dma_buffer.dev.dev))
Patches currently in stable-queue which might be from sr@xxxxxxx are
queue-3.18/alsa-pcm-use-dma_bytes-as-size-parameter-in-dma_mmap_coherent.patch