Re: [PATCH] x86/AMD: Apply erratum 688 on machines without a BIOS fix

From: Borislav Petkov
Date: Sat Oct 22 2016 - 11:04:48 EST


On Sat, Oct 22, 2016 at 02:16:41PM +0300, sonofagun@xxxxxxxxxxxxxxx wrote:
> Patch does not compile.

Yeah, it needs more work.

Try the version below. It needs to be done differently because we need
PCI extended config space access to be enabled in order to check bit 2.

> To be honest I can't say. My brother's machine(s) has random crashes from
> time to time. We suspect that this erratum is to blame. He must have kept
> some information at least from one of those crashes but there was no time to
> analyze them till now. Finding those logs on our disks needs a big effort
> but it will be done! We are willing to discover the trouble maker no matter
> what it takes. To do that the machine must be stripped off from all cards
> and then put on quarantine. Then we can connect it with a another machine
> with an RS-232 cable to see what is wrong. After that we must test it on a
> different motherboard we have. I think we have one with a BIOS from a
> different BIOS vendor. We will surely inform you on this one as we can't do
> such a patch. So we will focus on triggering this bug. One thing is sure,
> its BIOS has no workaround for that erratum.

Ok, good. Let me know how it goes.

Thanks.

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