On Mon, Oct 22, 2018 at 5:27 AM Peter Xu <pet...@redhat.com> wrote: > > On Mon, Oct 22, 2018 at 12:22:02AM -0400, Jintack Lim wrote: > > Hi, > > > > I wonder if vIOMMU is working for Windows VM? > > > > I tried it with v2.11.0, but it didn't seem to work. I assume that seaBIOS > > sets IOMMU on by default as is the case when I launched a Linux VM. But I > > might be missing something. Can somebody shed some light on it? > > Hi, Jintack, >
Thanks Peter, > I think at least the latest QEMU should work for Windows, but I don't > really run Windows that frequently. > > What is the error you've encountered? Have you tried the latest QEMU, > or switching Windows versions to try? I ran Windows commands in Windows Powershell like below. Well, I guess this is not the best way to check IOMMU presence, but couldn't find a better way to do it. $ (Get-VMHost).IovSupport false $ (Get-VMHost).IovSupportReasons The chipset on the system does not do DMA remapping, ... I just tried QEMU v3.0.0, but I see the same symptom. I'm using Windows server 2016. Unfortunately, trying another Windows version would be hard for me at this point. I just wonder if there's way to check if Vt-d is on in SeaBIOS? > > What I can remember about Windows is that Ladi had fixed a bug for > windows-only (8991c460be, "intel_iommu: relax iq tail check on > VTD_GCMD_QIE enable", 2017-07-03) but it should be even in 2.10 so I > guess it's not the problem you've encountered. I'm CCing Ladi, just in case he has some idea :) Thanks, Jintack > > Regards, > > -- > Peter Xu >
