linux-kernel - Re: [PATCH 3/4] KVM: MMU: notrap it if gpte's reserved is set

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:	Wed, 17 Nov 2010 09:45:03 +0800
From:	Xiao Guangrong <xiaoguangrong@...fujitsu.com>
To:	Avi Kivity <avi@...hat.com>
CC:	Marcelo Tosatti <mtosatti@...hat.com>,
	LKML <linux-kernel@...r.kernel.org>, KVM <kvm@...r.kernel.org>
Subject: Re: [PATCH 3/4] KVM: MMU: notrap it if gpte's reserved is set

On 11/15/2010 05:17 PM, Avi Kivity wrote:
> On 11/15/2010 07:41 AM, Xiao Guangrong wrote:
>> On 11/14/2010 06:56 PM, Avi Kivity wrote:
>> >  On 11/12/2010 12:34 PM, Xiao Guangrong wrote:
>> >>  We can past the page fault to guest directly if gpte's reserved
>> >>  is set
>> >>
>> >
>> >  How can that work? shadow_notrap_nonpresent_pte causes a fault with
>> >  PFEC.P=PFEC.RSVD=0, while we need PFEC.P=PFEC.RSVD=1.
>> >
>>
>> Ah, i missed it for a long time, thanks for you point it out.
>>
>> The same mistake is in 'prefetch' path, i'll fix it in the v2 version.
> 
> Doesn't access.flat catch this?

Unfortunately, it can't catch this.

> 
> Ideally we'd have a test case to catch this, but it may be hard to write.
> 

Um. i'll do it later.

--
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/