Re: [PATCH] x86, CPU, AMD: Add workaround for family 16h, erratum 793

Pavel Machek
2014-01-18T11:08:33Z

On Sat 2014-01-18 11:42:31, Borislav Petkov wrote:
> On Sat, Jan 18, 2014 at 03:01:55AM +0100, Pavel Machek wrote:
> > I'd say that proposed "your bios has a bug"
>
> You can always unconditionally print "your bios has a bug". Just like
> that. Without even looking.

Yeah, and we have linux-firmware testing toolkits, to discourage buggy
bioses. In this case it is "your bios has rare and dangerous bug, see CVS-1234".

> If you want to add a warning yourself, you can put it in rc.local using
> userspace goodies like msr-tools. With them you can toggle that bit ad
> absurdum - no need for the kernel except msr.ko.

?? By the time userspace is booted, you have overwritten the MSR, and
information, if the BIOS is buggy, was lost.

So linux-firmware testing toolkit actually has no chance to report
this one.

Pavel
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