[alsa-devel] [PATCH]: x86_64, audio: Fix system panic when DMA > 40 bits

[Mike Travis]

The audio driver mistakenly allows 64 bit addresses to be created for
the audio driver on Nvidia GPUs.  Unfortunately, the hardware normally
only supports up to 40 bits of DMA.  This can cause system panics as
well as misdirected data when the address is > 40 bits as the upper
part the address is truncated.

Signed-off-by: Mike Travis <travis at sgi.com>
Reviewed-by: Mike Habeck <habeck at sgi.com>
---
 sound/pci/hda/hda_intel.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index bcd40ee..45eb165 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -615,7 +615,7 @@ enum {
 /* quirks for Nvidia */
 #define AZX_DCAPS_PRESET_NVIDIA \
 	(AZX_DCAPS_NVIDIA_SNOOP | AZX_DCAPS_RIRB_DELAY | AZX_DCAPS_NO_MSI |\
-	 AZX_DCAPS_ALIGN_BUFSIZE)
+	 AZX_DCAPS_ALIGN_BUFSIZE | AZX_DCAPS_NO_64BIT)
 
 #define AZX_DCAPS_PRESET_CTHDA \
 	(AZX_DCAPS_NO_MSI | AZX_DCAPS_POSFIX_LPIB | AZX_DCAPS_4K_BDLE_BOUNDARY)
-- 
1.8.2.1