linux-kernel - Re: [PATCH 4/4] KVM MMU: do not intercept invlpg if 'oos

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-next>] [day] [month] [year] [list]

Message-ID: <4BDAA94A.8050407@redhat.com>
Date:	Fri, 30 Apr 2010 12:56:26 +0300
From:	Avi Kivity <avi@...hat.com>
To:	Xiao Guangrong <xiaoguangrong@...fujitsu.com>
CC:	Marcelo Tosatti <mtosatti@...hat.com>,
	KVM list <kvm@...r.kernel.org>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 4/4] KVM MMU: do not intercept invlpg if 'oos_shadow'
 is disabled

On 04/30/2010 12:05 PM, Xiao Guangrong wrote:
> If 'oos_shadow' == 0, intercepting invlpg command is really
> unnecessary.
>
> And it's good for us to compare the performance between enable 'oos_shadow'
> and disable 'oos_shadow'
>
> @@ -74,8 +74,9 @@ static int dbg = 0;
>   module_param(dbg, bool, 0644);
>   #endif
>
> -static int oos_shadow = 1;
> +int __read_mostly oos_shadow = 1;
>   module_param(oos_shadow, bool, 0644);
> +EXPORT_SYMBOL_GPL(oos_shadow);
>    

Please rename to kvm_oos_shadow to reduce potential for conflict with 
other global names.

But really, this is a debug option, I don't expect people to run with 
oos_shadow=0, so there's not much motivation to optimize it.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.

--
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/