Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755748Ab3EBI3p (ORCPT ); Thu, 2 May 2013 04:29:45 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:33376 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751746Ab3EBI3l (ORCPT ); Thu, 2 May 2013 04:29:41 -0400 Message-ID: <518223ED.3000509@canonical.com> Date: Thu, 02 May 2013 10:29:33 +0200 From: David Henningsson User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130329 Thunderbird/17.0.5 MIME-Version: 1.0 To: Mike Travis CC: Stephen Warren , Jaroslav Kysela , Takashi Iwai , Pierre-Louis Bossart , alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, Russ Anderson Subject: Re: [PATCH]: x86_64, audio: Fix system panic when DMA > 40 bits References: <1367435048-66137-1-git-send-email-travis@sgi.com> <518205A9.1050409@canonical.com> <51820968.7080303@sgi.com> In-Reply-To: <51820968.7080303@sgi.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2175 Lines: 64 On 05/02/2013 08:36 AM, Mike Travis wrote: > > > On 5/1/2013 11:20 PM, David Henningsson wrote: >> On 05/01/2013 09:04 PM, Mike Travis wrote: >>> 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. >> >> Thanks for this patch. Stephen Warren, is this something you can >> confirm/deny, and do you know what range of hardware this actually >> applies to? > > The dma_mask can be read from the gpu device's pci entry. I know it's > a stretch to try to link to that but past history has shown that it > ranges from 36 to 40 bits. Ok, so the below patch is some kind of workaround, as we don't currently take the dma_mask into account correctly? Or put in another way, would it be possible/better to actually read the dma_mask and use that instead of just clamping at 32 bit? > >> >>> >>> Signed-off-by: Mike Travis >>> Reviewed-by: Mike Habeck >>> --- >>> 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) >>> >> >> >> > -- David Henningsson, Canonical Ltd. https://launchpad.net/~diwic -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/