On 2017-05-16 09:11, Corbin Bird wrote: > > http://bogdan.org.ua/2009/09/30/iommu-this-costs-you-64-mb-of-ram.html > > That link, read the rest of it. > > It says to leave it alone, let the kernel use it as an IOMMU. > > On AMD, with NO IOMMU kernel parameters, output in '/var/log/dmesg': > NOTE : IOMMU is enabled in the UEFI firmware. > > > [ 0.000000] AGP: Checking aperture... > > [ 0.000000] AGP: No AGP bridge found > > [ 0.000000] AGP: Node 0: aperture [bus addr 0xb4000000-0xb5ffffff] (32MB) > > [ 0.000000] Aperture pointing to e820 RAM. Ignoring. > > [ 0.000000] AGP: Your BIOS doesn't leave an aperture memory hole > > [ 0.000000] AGP: Please enable the IOMMU option in the BIOS setup > > [ 0.000000] AGP: This costs you 64MB of RAM > > [ 0.000000] AGP: Mapping aperture over RAM [mem 0xb4000000-0xb7ffffff] > > (65536KB) > > > [ 0.926772] PCI: CLS 64 bytes, default 64 > > [ 0.926983] PCI-DMA: Disabling AGP. > > [ 0.927215] PCI-DMA: aperture base @ b4000000 size 65536 KB > > [ 0.927336] PCI-DMA: using GART IOMMU. > > [ 0.927448] PCI-DMA: Reserving 64MB of IOMMU area in the AGP aperture
And that is exactly what I get. It was you who suggested starting to add iommu=blah to the kernel args. -- Please *no* private Cc: on mailing lists and newsgroups Personal signed mail: please _encrypt_ and sign Don't clear-text sign: http://primate.net/~itz/blog/the-problem-with-gpg-signatures.html
