kvmarm.lists.cs.columbia.edu archive mirror
 help / color / mirror / Atom feed
From: Christoffer Dall <cdall@linaro.org>
To: Raz <raziebe@gmail.com>
Cc: kvmarm@lists.cs.columbia.edu
Subject: Re: unmap_ptes is not complete
Date: Wed, 29 Nov 2017 19:08:44 +0100	[thread overview]
Message-ID: <20171129180844.GF10563@lvm> (raw)
In-Reply-To: <CAPB=Z-piv-Fe+7p9xH8TuZ=xH6oJHmh2+g+Dk6gJRagixseL_Q@mail.gmail.com>

Hi Raz,

On Mon, Nov 27, 2017 at 09:10:56PM +0000, Raz wrote:
> Hey
> in mmu.c unmap_ptes() you invalidate *pte but not the pte itself. This
> leads to inconsistency in el2 translation tables. ie; the pte entry is
> cleared in the cached memory but not in the RAM, so the entry may still be
> valid in EL2 translation tables.

I'm not sure which code you're talking about.  Perhaps try sending a
patch?

> You should also clear pte itself.
> 

If you're talking about unmap_stage2_ptes(), then I must be missing
something, because I don't see why setting the pointer to 0 should
matter, and what you say about cached memory and RAM doesn't sound
correct, as all virtualization-capable ARM CPUs have coherent page table
walks.

Thanks,
-Christoffer

      reply	other threads:[~2017-11-29 18:05 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-11-27 21:10 unmap_ptes is not complete Raz
2017-11-29 18:08 ` Christoffer Dall [this message]

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=20171129180844.GF10563@lvm \
    --to=cdall@linaro.org \
    --cc=kvmarm@lists.cs.columbia.edu \
    --cc=raziebe@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 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).