linux-kernel - Re: [PATCH] x86: Construct 32 bit boot time page tables in native format.

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]

Message-ID: <479E4918.3010204@zytor.com>
Date:	Mon, 28 Jan 2008 13:28:56 -0800
From:	"H. Peter Anvin" <hpa@...or.com>
To:	"Rafael J. Wysocki" <rjw@...k.pl>
CC:	Jeremy Fitzhardinge <jeremy@...p.org>, Pavel Machek <pavel@....cz>,
	Ingo Molnar <mingo@...e.hu>, Ian Campbell <ijc@...lion.org.uk>,
	Mika Penttilä <mika.penttila@...umbus.fi>,
	linux-kernel@...r.kernel.org, Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>,
	"Eric W. Biederman" <ebiederm@...ssion.com>
Subject: Re: [PATCH] x86: Construct 32 bit boot time page tables in native
 format.

Rafael J. Wysocki wrote:
> On Monday, 28 of January 2008, Jeremy Fitzhardinge wrote:
>> Rafael J. Wysocki wrote:
>>> Actually, no.  We only do that with the kernel code mapping which should be
>>> safe as long as TLBs are not flushed (and they aren't).
>>>   
>> Er, what?  Assuming the TLB will retain some mappings while you 
>> overwrite the pagetable is a highly dubious prospect.  Are you copying 
>> the same values over, or something else?
> 
> As long as a relocatable kernel is not used to restore a non-relocatable one
> (or vice versa), we're copying the same values over.
> 

So that case is deliberately considered broken?

	-hpa
--
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/