From: Borislav Petkov <bp@alien8.de>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>,
Andy Lutomirski <luto@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
linux-kernel@vger.kernel.org, Dave Hansen <dave.hansen@intel.com>,
Chang Seok Bae <chang.seok.bae@intel.com>,
Peter Zijlstra <peterz@infradead.org>,
Sasha Levin <sashal@kernel.org>,
kvm@vger.kernel.org, Tom Lendacky <thomas.lendacky@amd.com>
Subject: Re: [PATCH] x86/entry/64: Disallow RDPID in paranoid entry if KVM is enabled
Date: Fri, 21 Aug 2020 10:16:33 +0200 [thread overview]
Message-ID: <20200821081633.GD12181@zn.tnic> (raw)
In-Reply-To: <3eb94913-662d-5423-21b1-eaf75635142a@redhat.com>
On Fri, Aug 21, 2020 at 10:09:01AM +0200, Paolo Bonzini wrote:
> One more MSR *is* a big deal: KVM's vmentry+vmexit cost is around 1000
> cycles, adding 100 clock cycles for 2 WRMSRs is a 10% increase.
The kernel uses TSC_AUX so we can't reserve it to KVM either.
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
next prev parent reply other threads:[~2020-08-21 8:16 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-21 2:50 [PATCH] x86/entry/64: Disallow RDPID in paranoid entry if KVM is enabled Sean Christopherson
2020-08-21 7:24 ` peterz
2020-08-21 7:44 ` Borislav Petkov
2020-08-21 7:47 ` Borislav Petkov
2020-08-21 8:09 ` Paolo Bonzini
2020-08-21 8:16 ` Borislav Petkov [this message]
2020-08-21 9:05 ` Paolo Bonzini
2020-08-21 9:22 ` Borislav Petkov
2020-08-21 9:44 ` Paolo Bonzini
2020-08-21 9:48 ` Borislav Petkov
2020-08-21 10:07 ` Paolo Bonzini
2020-08-22 16:42 ` Andy Lutomirski
2020-09-16 16:54 ` Paolo Bonzini
2020-08-21 9:28 ` Thomas Gleixner
2020-08-21 9:37 ` Paolo Bonzini
2020-08-21 19:55 ` hpa
2020-08-21 20:02 ` Peter Zijlstra
2020-08-21 8:56 ` kernel test robot
2020-08-21 8:56 ` kernel test robot
2020-08-21 10:28 ` kernel test robot
2020-08-21 10:28 ` kernel test robot
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200821081633.GD12181@zn.tnic \
--to=bp@alien8.de \
--cc=chang.seok.bae@intel.com \
--cc=dave.hansen@intel.com \
--cc=hpa@zytor.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mingo@redhat.com \
--cc=pbonzini@redhat.com \
--cc=peterz@infradead.org \
--cc=sashal@kernel.org \
--cc=sean.j.christopherson@intel.com \
--cc=tglx@linutronix.de \
--cc=thomas.lendacky@amd.com \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.