From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zachary Richmond Subject: Re: DL385 G2 - PCI-DMA: Random memory would be DMAed Date: Fri, 19 Oct 2007 14:29:00 -0500 Message-ID: <4719057C.4060901@gmail.com> References: <4717C238.9060106@gmail.com> <1449F58C868D8D4E9C72945771150BDF020770A6@SAUSEXMB1.amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1449F58C868D8D4E9C72945771150BDF020770A6@SAUSEXMB1.amd.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel@lists.xensource.com Cc: "Langsdorf, Mark" List-Id: xen-devel@lists.xenproject.org Langsdorf, Mark wrote: >> To answer Mark's question: >> >> > What kernel are you using? >> >> from gentoo: xen-sources-2.6.20-r6 >> >> Regarding the full error message, all I am getting is: >> >> kernel panic not syncing: PCI-DMA: Random memory would be DMAed >> >> since the machine is rebooting after that. There maybe >> somewhere else to get more detail, but beyond dmesg or >> messages I am not sure where else to look. > > For some reason, your kernel is running with pci-gart.c > enabled, and dom0 is trying to allocate DMA through the > AGP GART in your AMD64 processor's Northbridge. I > didn't think Xen supported pci-gart, but maybe I missed > a changeset. > > At any rate, passing iommu=soft should disable the pci-gart > and allow you to use bounce buffering. Hopefully, that > should clear up your problem. > > -Mark Langsdorf > Operating System Research Center > AMD > > > Unfortunately I am still having the problem. Having booted off a cd to preserve log files a quick grep on dmesg shows: PCI-DMA: Using software bounce buffering for IO (SWIOTLB) So it is enabled, but still the kernel panic. Any other ideas on where to poke around? Thanks, Zak