From: Paolo Bonzini <pbonzini@redhat.com>
To: Hu Yaohui <loki2441@gmail.com>, kvm <kvm@vger.kernel.org>
Subject: Re: Nested EPT Write Protection
Date: Fri, 19 Jun 2015 08:27:07 +0200 [thread overview]
Message-ID: <5583B63B.1080907@redhat.com> (raw)
In-Reply-To: <CAHqbYQvzU=U=SrNeip_zjWkQAdu2Sfwd1nPfYuJ012xPUrTKdw@mail.gmail.com>
On 19/06/2015 03:52, Hu Yaohui wrote:
> Hi All,
> In kernel 3.14.2, the kvm uses shadow EPT(EPT02) to implement the
> nested EPT. The shadow EPT(EPT02) is a shadow of guest EPT (EPT12). If
> the L1 guest writes to the guest EPT(EPT12). How can the shadow
> EPT(EPT02) be modified according?
Because the EPT02 is write protected, writes to the EPT12 will trap to
the hypervisor. The hypervisor will execute the write instruction
before reentering the guest and invalidate the modified parts of the
EPT02. When the invalidated part of the EPT02 is accessed, the
hypervisor will rebuild it according to the EPT12 and the KVM memslots.
Paolo
next prev parent reply other threads:[~2015-06-19 6:27 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-19 1:52 Nested EPT Write Protection Hu Yaohui
2015-06-19 6:27 ` Paolo Bonzini [this message]
2015-06-19 12:44 ` Hu Yaohui
2015-06-19 15:23 ` Paolo Bonzini
2015-06-19 18:57 ` Hu Yaohui
2015-06-22 11:26 ` Paolo Bonzini
[not found] ` <CAHqbYQsXfmQfBGva2t_VSFMQj3dnwUUcFPBbvnQDN_tR0y3i8g@mail.gmail.com>
2015-06-22 13:59 ` 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=5583B63B.1080907@redhat.com \
--to=pbonzini@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=loki2441@gmail.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 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.