On Sat, Dec 17, 2011 at 7:54 AM, Joshua C. <joshuacov@xxxxxxxxxxxxxx> wrote: > I saw in the change log for the kernel-3.1.5-7 that the Intel IOMMU > has been disabled by default. Can someone explain this decision or > point me to the right discussion on the internet? Dave or Matthew can answer more fully than I can, but there is an on-going patch series to reenable Sandybridge GPU power savings and DMAR conflicts with it some how. I don't recall the details, but you can find them in the discussions between Matthew and Keith Packard on LKML. Defaulting this to on has caused a number of odd issues in the past, and it is mostly used by people using VT-d to assign physical resources directly to virtual guests. Those doing that can still boot with intel_iommu=on. josh _______________________________________________ kernel mailing list kernel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/kernel
