From: Paolo Bonzini <pbonzini@redhat.com>
To: Sean Christopherson <sean.j.christopherson@intel.com>,
Tao Xu <tao3.xu@intel.com>, Jingqi Liu <jingqi.liu@intel.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [RESEND] Atomic switch of MSR_IA32_UMWAIT_CONTROL
Date: Thu, 23 Jan 2020 17:16:06 +0100 [thread overview]
Message-ID: <c8371569-78f5-24bc-d4c0-2c7f8f3c1f14@redhat.com> (raw)
In-Reply-To: <20200123154526.GC13178@linux.intel.com>
On 23/01/20 16:45, Sean Christopherson wrote:
> cc'ing KVM and LKML this time...
>
> Why does KVM use the atomic load/store lists to load MSR_IA32_UMWAIT_CONTROL
> on VM-Enter/VM-Exit? Unless the host kernel is doing UWMAIT, which it
> really shouldn't and AFAICT doesn't, isn't it better to use the shared MSR
> mechanism to load the host value only when returning to userspace, and
> reload the guest value on demand?
Just laziness I guess.
Paolo
next prev parent reply other threads:[~2020-01-23 16:16 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-23 15:45 [RESEND] Atomic switch of MSR_IA32_UMWAIT_CONTROL Sean Christopherson
2020-01-23 16:16 ` Paolo Bonzini [this message]
2020-01-23 16:16 ` Paolo Bonzini
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=c8371569-78f5-24bc-d4c0-2c7f8f3c1f14@redhat.com \
--to=pbonzini@redhat.com \
--cc=jingqi.liu@intel.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=sean.j.christopherson@intel.com \
--cc=tao3.xu@intel.com \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).