Re: Boot regression with bacf6b499e11 ("x86/mm: Use a struct to reduce parameters for SME PGD mapping") on top of -rc8

[Tom Lendacky]

On 1/19/2018 8:38 PM, Linus Torvalds wrote:
> On Fri, Jan 19, 2018 at 5:23 PM, Laura Abbott <labbott@xxxxxxxxxx> wrote:
>>
>> Fedora got multiple reports of an early bootup crash post -rc8.
>> Bisection showed bacf6b499e11 ("x86/mm: Use a struct to reduce
>> parameters for SME PGD mapping") . It doesn't revert cleanly
>> but if I revert the few other changes in arch/x86/mm/mem_encrypt.c
>> as well it boots up fine.
> 
> Odd. I've tried to read through that patch three times to find
> anything it actually changes, and I can't find anything.
> 
> It looks like that patch should have absolutely no actual behavioral impact.
> 
> But clearly I'm missing something. Can anybody see what the mistake in
> the conversion is?

I'll take a closer look at this, but it really shouldn't have any effect,
especially on a non-AMD box (which I'm assuming this is?) and with memory
encryption off by default.

Thanks,
Tom

> 
>              Linus
>