LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: "Kirill A. Shutemov" <kirill@shutemov.name>
To: Matthew Wilcox <willy@infradead.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
	tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
	hpa@zytor.com, dave.hansen@linux.intel.com, luto@kernel.org,
	peterz@infradead.org, x86@kernel.org, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] x86/mm: Move LDT remap out of KASLR region on 5-level paging
Date: Wed, 24 Oct 2018 15:44:43 +0300	[thread overview]
Message-ID: <20181024124443.husnnxgligsncm5t@kshutemo-mobl1> (raw)
In-Reply-To: <20181024115447.GE25444@bombadil.infradead.org>

On Wed, Oct 24, 2018 at 04:54:47AM -0700, Matthew Wilcox wrote:
> On Tue, Oct 23, 2018 at 07:31:56PM +0300, Kirill A. Shutemov wrote:
> > -ffff880000000000 - ffffc7ffffffffff (=64 TB) direct mapping of all phys. memory
> > +ffff888000000000 - ffff887fffffffff (=39 bits) LDT remap for PTI
> 
> I'm a little bit cross-eyed at this point, but I think the above '888'
> should be '880'.
> 
> > @@ -14,7 +15,6 @@ ffffec0000000000 - fffffbffffffffff (=44 bits) kasan shadow memory (16TB)
> >  ... unused hole ...
> >  				    vaddr_end for KASLR
> >  fffffe0000000000 - fffffe7fffffffff (=39 bits) cpu_entry_area mapping
> > -fffffe8000000000 - fffffeffffffffff (=39 bits) LDT remap for PTI
> 
> ... and the line above this one should be adjusted to finish at
> fffffeffffffffff (also it's now 40 bits).  Or should there be something
> else here?
> 
> >  ffffff0000000000 - ffffff7fffffffff (=39 bits) %esp fixup stacks
> >  ... unused hole ...
> >  ffffffef00000000 - fffffffeffffffff (=64 GB) EFI region mapping space
> > @@ -30,8 +30,8 @@ Virtual memory map with 5 level page tables:
> >  0000000000000000 - 00ffffffffffffff (=56 bits) user space, different per mm
> >  hole caused by [56:63] sign extension
> >  ff00000000000000 - ff0fffffffffffff (=52 bits) guard hole, reserved for hypervisor
> > -ff10000000000000 - ff8fffffffffffff (=55 bits) direct mapping of all phys. memory
> > -ff90000000000000 - ff9fffffffffffff (=52 bits) LDT remap for PTI
> > +ff10000000000000 - ff10ffffffffffff (=48 bits) LDT remap for PTI
> > +ff11000000000000 - ff90ffffffffffff (=55 bits) direct mapping of all phys. memory
> 
> What's at ff910..0 to ff9f..f ?
> 
> Is there any way we can generate this part of this file to prevent human
> error from creeping in over time?  ;-)

In current Linus' tree this part of the documentation was re-written. I've
rebased to it and rewrote the documenation for the change.

I believe I've fixed all mistakes you've noticied. Please check out v2. I
will post it soon.

-- 
 Kirill A. Shutemov

  reply	other threads:[~2018-10-24 12:44 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-10-23 16:31 [PATCH 0/2] Fix couple of issues with LDT remap for PTI Kirill A. Shutemov
2018-10-23 16:31 ` [PATCH 1/2] x86/mm: Move LDT remap out of KASLR region on 5-level paging Kirill A. Shutemov
2018-10-24 11:54   ` Matthew Wilcox
2018-10-24 12:44     ` Kirill A. Shutemov [this message]
2018-10-23 16:31 ` [PATCH 2/2] x86/ldt: Unmap PTEs for the slow before freeing LDT Kirill A. Shutemov
2018-10-24 11:12   ` Christoph Hellwig
2018-10-24 18:49   ` Andy Lutomirski
2018-10-25  7:26     ` Kirill A. Shutemov
2018-10-24 19:39   ` H. Peter Anvin

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=20181024124443.husnnxgligsncm5t@kshutemo-mobl1 \
    --to=kirill@shutemov.name \
    --cc=bp@alien8.de \
    --cc=dave.hansen@linux.intel.com \
    --cc=hpa@zytor.com \
    --cc=kirill.shutemov@linux.intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=luto@kernel.org \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.org \
    --cc=tglx@linutronix.de \
    --cc=willy@infradead.org \
    --cc=x86@kernel.org \
    --subject='Re: [PATCH 1/2] x86/mm: Move LDT remap out of KASLR region on 5-level paging' \
    /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

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).