From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
To: Michael Zimmermann <sigmaepsilon92@gmail.com>
Cc: Laszlo Ersek <lersek@redhat.com>,
"edk2-devel@lists.01.org" <edk2-devel@ml01.01.org>
Subject: Re: post-ExitBootServices memory protection of RT_Data (ARM)
Date: Fri, 2 Sep 2016 22:02:35 +0100 [thread overview]
Message-ID: <CAKv+Gu8NMVSgWqmVcgghX8iHjKSDAKe0S62ixD5uAppFZxdgcQ@mail.gmail.com> (raw)
In-Reply-To: <CAN9vWDL3SJx_eix92+JjFUrAmRek0GKbGM4XYWH3JBCHFSz2Hw@mail.gmail.com>
On 2 September 2016 at 21:45, Michael Zimmermann
<sigmaepsilon92@gmail.com> wrote:
> If I understand this correctly this is just some MMU feature, right?
> I'm talking about a pure ARM(with atag's) linux kernel which is not UEFI
> aware.
>
> Also the LinuxLoader disables almost everything(MMU, caches, it calls
> exitbootservices etc).
>
> I really can't explain technically what UEFI could have done to accomplish
> this protection with the MMU being disabled.
>
No, the kernel is entered with the MMU and caches off. The LinuxLoader
is a poorly maintained hack, and it is badly broken on AARCH64. On
ARM, however, it should still work. Does the system have an L2 cache
which may need invalidation/disabling?
next prev parent reply other threads:[~2016-09-02 21:02 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-02 13:08 post-ExitBootServices memory protection of RT_Data (ARM) Michael Zimmermann
2016-09-02 20:30 ` Laszlo Ersek
2016-09-02 20:45 ` Michael Zimmermann
2016-09-02 21:02 ` Ard Biesheuvel [this message]
2016-09-03 4:04 ` Michael Zimmermann
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-list 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=CAKv+Gu8NMVSgWqmVcgghX8iHjKSDAKe0S62ixD5uAppFZxdgcQ@mail.gmail.com \
--to=devel@edk2.groups.io \
/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