linux-kernel - Re: [PATCH] Revert "x86-64, init: Do not set NX bits on non-NX capable hardware"

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: <519A67C9.6000709@linux.intel.com>
Date:	Mon, 20 May 2013 11:13:29 -0700
From:	"H. Peter Anvin" <hpa@...ux.intel.com>
To:	Linus Torvalds <torvalds@...ux-foundation.org>
CC:	Michal Hocko <mhocko@...e.cz>, "H. Peter Anvin" <hpa@...or.com>,
	Fernando Luis Vázquez Cao 
	<fernando@....ntt.co.jp>, "Rafael J. Wysocki" <rjw@...k.pl>,
	the arch/x86 maintainers <x86@...nel.org>,
	"linux-pm@...r.kernel.org" <linux-pm@...r.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] Revert "x86-64, init: Do not set NX bits on non-NX capable
 hardware"

On 05/20/2013 10:21 AM, Linus Torvalds wrote:
> On Mon, May 20, 2013 at 9:43 AM, Michal Hocko <mhocko@...e.cz> wrote:
>>
>> The configuration has been posted in the referenced thread:
>> https://lkml.org/lkml/2013/5/14/398
> 
> Hmm. That's a regular intel i5 Sandybridge CPU. Which certainly has NX.
> 
> Hmm. secondary_startup_64 isn't __initcode, is it? I think it's used
> for resuming the other CPU's too and for CPU hotplug. Yes/no?
> 
> If so early_pmd_flags shouldn't be __initdata, I think.
> 
> Michal, does it work if you don't do the revert, but just remove the
> __initdata instead?
> 

Indeed.  Looks like we corrupt a random bit in memory on resume.

	-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/