Message-ID: <046992ea-c201-016d-ee59-e1af72d8a6d8@amd.com>
Date:   Tue, 14 Feb 2023 08:27:47 -0600
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Subject: Re: [PATCH v14 1/3] virt/coco/sev-guest: Add throttling awareness
To:     Dionna Amalie Glaze <dionnaglaze@google.com>
Cc:     linux-kernel@vger.kernel.org, x86@kernel.org,
        Paolo Bonzini <pbonzini@redhat.com>,
        Joerg Roedel <jroedel@suse.de>,
        Peter Gonda <pgonda@google.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Ingo Molnar <mingo@redhat.com>,
        Borislav Petkov <Borislav.Petkov@amd.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Venu Busireddy <venu.busireddy@oracle.com>,
        Michael Roth <michael.roth@amd.com>,
        "Kirill A. Shutemov" <kirill@shutemov.name>,
        Michael Sterritt <sterritt@google.com>
References: <20230213172525.575766-1-dionnaglaze@google.com>
 <20230213172525.575766-2-dionnaglaze@google.com>
 <22e96dfd-21af-681c-22d2-12bcc082f63e@amd.com>
 <CAAH4kHYrz2pZzwAqoy-mpA_om1+tO8qB-4ZHc9jKh_ucwZe3OQ@mail.gmail.com>
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From:   Tom Lendacky <thomas.lendacky@amd.com>
In-Reply-To: <CAAH4kHYrz2pZzwAqoy-mpA_om1+tO8qB-4ZHc9jKh_ucwZe3OQ@mail.gmail.com>
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On 2/13/23 16:28, Dionna Amalie Glaze wrote:
>>
>> This should really be a new, separate patch.
>>
> 
> I had it as a separate patch and squashed since I felt it necessary to
> be considered still a "Fixes" patch. Should both claim to fix the same
> patch?

If they both fix a bug, yes. You can have multiple patches that fix 
different bugs that were all introduced by one commit.

Thanks,
Tom

> 
>>
>> It looks like you will ensure throttling by continually calling the
>> hypervisor for 60 seconds, shouldn't there be a delay here?
>>
> 
> I can change cond_resched() to sleep_timeout_killable(some_constant)
> 
>>> -             rc = snp_issue_guest_request(exit_code, &snp_dev->input, &err);
>>> +             cond_resched();
>>> +             goto retry;
>>>
>>> +     }
>>
>> Nit, add a blank line here.
>>
> 
> Will do.
> 
>> Thanks,
>> Tom
>>
> 
>