From: Paolo Bonzini <pbonzini@redhat.com>
To: Andy Lutomirski <luto@amacapital.net>,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Wanpeng Li <wanpeng.li@linux.intel.com>,
Fenghua Yu <fenghua.yu@intel.com>,
stable@vger.kernel.org, Nadav Amit <namit@cs.technion.ac.il>
Subject: Re: [CFT PATCH 2/2] KVM: x86: support XSAVES usage in the host
Date: Fri, 21 Nov 2014 22:58:19 +0100 [thread overview]
Message-ID: <546FB57B.3000303@redhat.com> (raw)
In-Reply-To: <546F9B59.7060800@amacapital.net>
On 21/11/2014 21:06, Andy Lutomirski wrote:
>> > + cpuid_count(XSTATE_CPUID, index,
>> > + &size, &offset, &ecx, &edx);
>> > + memcpy(dest + offset, src, size);
> Is this really the best way to do this? cpuid is serializing, so this
> is possibly *very* slow.
The data is in arch/x86/kernel/xsave.c, but it is not exported. But
this is absolutely not a hotspot.
Paolo
next prev parent reply other threads:[~2014-11-21 21:58 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1416594678-13011-1-git-send-email-pbonzini@redhat.com>
2014-11-21 18:31 ` [CFT PATCH 1/2] kvm: x86: mask out XSAVES Paolo Bonzini
2014-11-21 18:31 ` [CFT PATCH 2/2] KVM: x86: support XSAVES usage in the host Paolo Bonzini
2014-11-21 20:06 ` Andy Lutomirski
2014-11-21 21:58 ` Paolo Bonzini [this message]
2014-11-24 2:10 ` Wanpeng Li
2014-11-24 10:07 ` Paolo Bonzini
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