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Date:   Tue, 10 Oct 2023 15:20:02 +0300
From:   =?UTF-8?Q?Jos=C3=A9_Pekkarinen?= <jose.pekkarinen@foxhound.fi>
To:     Paolo Bonzini <pbonzini@redhat.com>
Cc:     Greg KH <gregkh@linuxfoundation.org>, seanjc@google.com,
        skhan@linuxfoundation.org, dave.hansen@linux.intel.com,
        kvm@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org,
        mingo@redhat.com, bp@alien8.de, hpa@zytor.com, tglx@linutronix.de,
        linux-kernel-mentees@lists.linuxfoundation.org
Subject: Re: [PATCH] kvm/sev: make SEV/SEV-ES asids configurable
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References: <20231010100441.30950-1-jose.pekkarinen@foxhound.fi>
 <2023101050-scuff-overstay-9b43@gregkh>
 <5c19c422-41ad-430b-664c-15f3e2087922@redhat.com>
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On 2023-10-10 14:40, Paolo Bonzini wrote:
> On 10/10/23 13:35, Greg KH wrote:
>> On Tue, Oct 10, 2023 at 01:04:39PM +0300, José Pekkarinen wrote:
>>> There are bioses that doesn't allow to configure the
>>> number of asids allocated for SEV/SEV-ES, for those
>>> cases, the default behaviour allocates all the asids
>>> for SEV, leaving no room for SEV-ES to have some fun.
> 
> In addition to what Greg pointed out (and there are many more cases
> that have to be checked for errors, including possible overflows), why
> is it correct to just ignore what's in CPUID?

     I'll check if I can use cpuid info to improve this
for v2, I just noticed my cpu advertises sev_es but
the kernel doesn't activate it despite of the kvm_amd
parameter being set, so I tried to fix it this way, but
any comments or ideas for improvement are welcomed.

     Thanks!

     José.