Re: [PATCH v3 0/5] x86: SME: BSP/SME microcode update fix

From: Tom Lendacky
Date: Wed Jan 10 2018 - 16:26:13 EST


On 1/10/2018 3:14 PM, Gabriel C wrote:
> On 10.01.2018 20:25, Tom Lendacky wrote:
>
> Hi Tom ,
>
>> This patch series addresses an issue when SME is active and the BSP
>> is attempting to check for and load microcode during load_ucode_bsp().
>> Since the initrd has not been decrypted (yet) and the virtual address
>> of the initrd treats the memory as encrypted, the CPIO archive parsing
>> fails to locate the microcode.
>>
>> This series moves the encryption of the initrd into the early boot code
>> and encrypts it at the same time that the kernel is encrypted. Since
>> the initrd is now encrypted, the CPIO archive parsing succeeds in
>> properly locating the microcode.
>>
>> The following patches are included in this fix:
>> - Cleanup register saving in arch/x86/mm/mem_encrypt_boot.S
>> - Reduce parameters and complexity for creating the SME PGD mappings
>> - Centralize the use of the PMD flags used in sme_encrypt_kernel() in
>> ÂÂ preparation for using PTE flags also.
>> - Prepare sme_encrypt_kernel() to handle PAGE aligned encryption, not
>> ÂÂ just 2MB large page aligned encryption.
>> - Encrypt the initrd in sme_encrypt_kernel() when the kernel is being
>> ÂÂ encrypted.
>>
>> This patch series is based on tip/master.
>
> Is something in tip/master the patch serie need ?

That's just how I have to submit the patches. You could try applying them
onto whatever tree you like, I don't imagine any conflicts would be too
difficult to resolve if you encounter any.

Thanks,
Tom

>
> I would like to test the serie however tip/master
> breaks my box.. On tip/master there is no way to boot
> with mem_crypt=on with or without your patches.
>
> With mem_crypt=off the box at least boots to a point , seems APCI breaks
> on tip/master.
>
> If someone want to take a look , a dmesg of the broken boot can be found
> there:
>
> http://sigsegv.24-7.ro/~crazy/tip-master/dmesg-tip-master.txt
>
> Regards,
>
> Gabriel C
>
>