[SOLVED] DMAR errors related to Intel graphics

smsware · 2014-01-29 01:24:23

Every time I boot I got message like this:

dmar:DRHD: handling fault status reg 2
dmar:DMAR:[DMA Read] Request device [00:1f.2] fault addr caa40000
DMAR:[fault reason 06] PTE Read access is not set

I've googled that the errors should dissapear after setting intel_iommu=off or intel_iommu=pt kernel parameter but for me it's not working at all. I've only learned that I shoudn't ignore this error as it affects performance (which is correct as my fps in games dropped badly) and destroy filesystems (I don't understand why as it suppouse to be problem with video driver).

What can I do?

Last edited by smsware (2014-01-29 05:22:42)

smsware · 2014-01-29 01:53:34

I solved it by disabling virtualization support in bios... I don't get a thing now but I'm not using it anyway so... solved?

Edit: not solved, sorry, it was just for one reboot, probably prompt didn't appear for some reason...

Last edited by smsware (2014-01-29 02:00:26)

smsware · 2014-01-29 05:22:28

Okay, so basically the command needs to be intel_iommu=igfx_off now (this error is rare and my previous search gave me solution from 2009) and it fixed the issue. As I've learned, the error is because dmar tables or my BIOS are broken... don't really know what it does, I'll check for upgrade but it's not Linux fault so I'm markin it as solved after all...

cambion.web · 2017-09-29 19:57:11

After updating kernel today I was getting this same issue.

Using coreboot BIOS on my T420 laptop, as far as I know the bios isn't broken but I reflashed that just in case. Didn't fix it.
Checked my dmar tables with "sudo ls -al /sys/firmware/acpi/tables" seemed fine.

Adding kernel parameter "intel_iommu=igfx_off" fixed the issue.

Thanks

Last edited by cambion.web (2017-09-29 19:57:49)

WorMzy · 2017-09-29 20:13:59

Please do not necrobump.

https://wiki.archlinux.org/index.php/Co … bumping.22

Closing.

Arch Linux

#1 2014-01-29 01:24:23

[SOLVED] DMAR errors related to Intel graphics

#2 2014-01-29 01:53:34

Re: [SOLVED] DMAR errors related to Intel graphics

#3 2014-01-29 05:22:28

Re: [SOLVED] DMAR errors related to Intel graphics

#4 2017-09-29 19:57:11

Re: [SOLVED] DMAR errors related to Intel graphics

#5 2017-09-29 20:13:59

Re: [SOLVED] DMAR errors related to Intel graphics

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