From: Mike Rapoport <rppt@kernel.org>
To: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mike Rapoport <rppt@linux.ibm.com>,
lsf-pc@lists.linux-foundation.org, linux-mm@kvack.org
Subject: Re: [LSF/MM/BPF TOPIC] Restricted kernel address spaces
Date: Tue, 18 Feb 2020 16:06:15 +0100 [thread overview]
Message-ID: <20200218150615.GA9478@hump> (raw)
In-Reply-To: <20200217103457.c3bmwp43fpa3ho4f@box>
On Mon, Feb 17, 2020 at 01:34:57PM +0300, Kirill A. Shutemov wrote:
> On Sun, Feb 16, 2020 at 08:35:04AM +0200, Mike Rapoport wrote:
> > > BTW, with clarified scope of the AMD Erratum, I believe we can implement
> > > "collapse" for direct mapping. Willing to try?
> >
> > My initial plan was to use a pool of large pages to satisfy "secret"
> > allocation requests. Whenever a new large page is allocated for that pool,
> > it's removed from the direct map without being split into small pages and
> > then when it would be reinstated back there would be no need to collapse
> > it.
>
> It might be okay. But you likely will have to split 1G pages in direct
> mapping into 2M.
Right, it is quite likely, at least for the dynamic allocations.
> Being able to repare the direct mapping is more generally
> useful.
And it's not strictly related to the "secret" memory. I'll try to have a
look at it.
> --
> Kirill A. Shutemov
--
Sincerely yours,
Mike.
prev parent reply other threads:[~2020-02-18 15:15 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-06 16:59 Mike Rapoport
2020-02-07 17:39 ` Kirill A. Shutemov
2020-02-11 17:20 ` Mike Rapoport
2020-02-11 21:53 ` Kirill A. Shutemov
2020-02-16 6:35 ` Mike Rapoport
2020-02-17 10:34 ` Kirill A. Shutemov
2020-02-18 15:06 ` Mike Rapoport [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=20200218150615.GA9478@hump \
--to=rppt@kernel.org \
--cc=kirill@shutemov.name \
--cc=linux-mm@kvack.org \
--cc=lsf-pc@lists.linux-foundation.org \
--cc=rppt@linux.ibm.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