linux-kernel - Re: [PATCH 02/11] x86/kexec: Add extra pointers to transition page table PGD, PUD, PMD and PTE

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 28 Sep 2012 08:56:50 +0100
From:	"Jan Beulich" <JBeulich@...e.com>
To:	"Daniel Kiper" <daniel.kiper@...cle.com>
Cc:	<andrew.cooper3@...rix.com>, "xen-devel" <xen-devel@...ts.xen.org>,
	<konrad.wilk@...cle.com>, <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 02/11] x86/kexec: Add extra pointers to transition
 page table PGD, PUD, PMD and PTE

>>> On 27.09.12 at 20:06, Daniel Kiper <daniel.kiper@...cle.com> wrote:
> Some implementations (e.g. Xen PVOPS) could not use part of identity page 
> table
> to construct transition page table. It means that they require separate 
> PUDs,
> PMDs and PTEs for virtual and physical (identity) mapping. To satisfy that
> requirement add extra pointer to PGD, PUD, PMD and PTE and align existing 
> code.

I'm puzzled by this - why would you need to reintroduce what had
been dropped a long time ago, when the forward ported kernels
don't need it? Xen itself doesn't need the extra entries, their
presence is purely a requirement of the specific kernel
implementation afaict.

Jan

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/