linux-kernel - Re: [PATCH] x86, paravirt: BUG

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: <53D6A1F2.5070404@zytor.com>
Date:	Mon, 28 Jul 2014 12:18:10 -0700
From:	"H. Peter Anvin" <hpa@...or.com>
To:	Eduardo Habkost <ehabkost@...hat.com>,
	virtualization@...ts.linux-foundation.org
CC:	Jeremy Fitzhardinge <jeremy@...p.org>,
	Chris Wright <chrisw@...s-sol.org>,
	Alok Kataria <akataria@...are.com>,
	Rusty Russell <rusty@...tcorp.com.au>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>, x86@...nel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] x86, paravirt: BUG_ON on {rd,wr}msr exceptions

On 07/28/2014 12:04 PM, Eduardo Habkost wrote:
> When CONFIG_PARAVIRT is enabled, the kernel is ignoring exceptions on
> the {rd,wr}msr instructions. This makes serious issues (either on the
> guest kernel, or on the host) be silently ignored, and is different from
> the native MSR code (which does not ignore the exceptions).
> 
> As paravirt.h already includes linux/bug.h, I don't see what was the
> original issue preventing BUG_ON from being used.
> 
> Change rdmsr(), wrmsr(), and rdmsrl() to BUG_ON() on errors.

How much does this bloat the kernel?

#include <stdparavirtrant.h>

	-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/