linux-kernel - Re: Builtin microcode does nothing..

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Message-ID: <86dacf1e-83ca-8dd9-c9b4-513c1e40dd2a@gmail.com>
Date:	Sat, 21 May 2016 04:59:15 +0200
From:	Gabriel C <nix.or.die@...il.com>
To:	Borislav Petkov <bp@...e.de>
Cc:	LKML <linux-kernel@...r.kernel.org>
Subject: Re: Builtin microcode does nothing..

On 21.05.2016 02:20, Gabriel C wrote:

> On 20.05.2016 12:08, Gabriel C wrote:
>
>>> Does it work when you disable CONFIG_BLK_DEV_INITRD in there?
>> I can test this when I'm home since I need to change the config a bit.
>
> I got to test an kernel without CONFIG_BLK_DEV_INITRD and this way 
> does work.
>

While that worked I read the code not sure I get this right but:

scan_microcode() has :

...
       if (!size) {
         if (!load_builtin_intel_microcode(&cd))
             return UCODE_ERROR;
     } else {
         cd = find_cpio_data(p, (void *)start, size, &offset);
         if (!cd.data)
             return UCODE_ERROR;
     }

...

So when I get this correctly load_builtin_intel_microcode() only works 
on !initrd ?

Should this check not be the other way around ?

something like :

       cd = find_cpio_data(p, (void *)start, size, &offset);
       if (!cd.data) {
            if (!load_builtin_intel_microcode(&cd))
                  return UCODE_ERROR;
       }

Regards,

Gabriel C