linux-kernel - Re: [PATCH 05/13] KVM: MMU: reset shadow_mmio

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: <4F748CDB.8020104@redhat.com>
Date:	Thu, 29 Mar 2012 18:24:59 +0200
From:	Avi Kivity <avi@...hat.com>
To:	Xiao Guangrong <xiaoguangrong@...ux.vnet.ibm.com>
CC:	Marcelo Tosatti <mtosatti@...hat.com>,
	LKML <linux-kernel@...r.kernel.org>, KVM <kvm@...r.kernel.org>
Subject: Re: [PATCH 05/13] KVM: MMU: reset shadow_mmio_mask

On 03/29/2012 05:28 PM, Avi Kivity wrote:
> On 03/29/2012 03:10 PM, Avi Kivity wrote:
> > On 03/29/2012 11:23 AM, Xiao Guangrong wrote:
> > > Do not use the last byte (bit 56 ~ bit 63) in shadow_mmio_mask, the late
> > > patch will store vcpu id in the last byte
> >
> > Bit 63 is PT64_NX_MASK.
>
> Oh, you did say that with softmmu we're limited to 127 cpus.  But what
> if spte.nx is changed while we update the identity?

Ok, saw that too.  But I think test_and_set_bit() is better here, to
reduce the complexity (note we need cmpxchg64b on 32-bit instead).

-- 
error compiling committee.c: too many arguments to function

--
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/