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On Friday 03 Feb 2017 09:03:10 Peter Humphrey wrote: |
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> On Thursday 02 Feb 2017 05:12:17 Dale wrote: |
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> > Peter Humphrey wrote: |
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> > > Hello list, |
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> > > |
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> > > I was looking through dmesg this morning and found 1231 instances (!) of |
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> > > this error: |
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> > > |
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> > > DMAR: DMAR:[DMA Read] Request device [01:00.0] fault addr f400156000 |
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> > > DMAR: [fault reason 06] PTE Read access is not set |
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> > > |
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> > > This is an Intel i7 box with an NVMe SSD and an AMD/ATI Amethyst XT |
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> > > Radeon R9 M295X display card. The kernel is gentoo-sources-4.4.39. I've |
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> > > tried setting intel_iommu=on or =pt as kernel parameter to no effect. I |
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> > > don't want to set it =off because I've read that it slows the machine |
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> > > dramatically. |
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> > > |
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> > > Googling has shown nothing, other than playing with that kernel |
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> > > parameter. Does anyone here know what the problem is? |
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> > |
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> > I'm not sure if it applies but I found this: |
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> > |
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> > https://forums.gentoo.org/viewtopic-p-7904584.html#7904584 |
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> > |
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> > It should scroll down a bit to the post. The last comment seems to have |
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> > a solution. |
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> > |
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> > Hope that helps. If not, maybe someone else has a better idea. |
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> |
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> Thanks, but no, it makes no difference here. |
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Peter, I recall a similar problem shown in the logs of an i7. and all I did |
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was to enable IOMMU in the kernel, just as a message in the logs recommended. |
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From memory I built in the kernel something like CONFIG_INTEL_IOMMU_DEFAULT_ON |
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as well as some Intel related IOMMU options. I did not pass any options on the |
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kernel line at boot time. The error messages stopped as a result. |
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-- |
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Regards, |
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Mick |
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