Re: [PATCH v8 06/16] virt: sev-guest: Move SNP Guest command mutex

From: Nikunj A. Dadhania
Date: Tue Apr 23 2024 - 00:23:12 EST


On 4/22/2024 6:30 PM, Borislav Petkov wrote:
> On Thu, Feb 15, 2024 at 05:01:18PM +0530, Nikunj A Dadhania wrote:
>> SNP command mutex is used to serialize the shared buffer access, command
>> handling and message sequence number races. Move the SNP guest command
>> mutex out of the sev guest driver and provide accessors to sev-guest
>
> And why in the hell are we doing this?

SNP guest messaging will be moving as part of sev.c, and Secure TSC code
will use this mutex.

> Always, *ALWAYS* make sure a patch's commit message answers *why*
> a change is done. This doesn't explain why so I'm reading "just because"
> and "just because" doesn't fly.

Sure, will change.

>
>> driver. Remove multiple lockdep check in sev-guest driver, next patch adds
>> a single lockdep check in snp_send_guest_request().
>
> The concept of "next patch" is meaningless once the patch is in git.

Sure. As direct access to the mutex was not available now, I had removed lockdep
check here and documented that lockdep gets added at later point.

Regards
Nikunj