linux-kernel - Re: 50 Watt idle power regression bisected to Linux-3.10

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: <alpine.DEB.2.02.1312111556390.28330@ionos.tec.linutronix.de>
Date:	Wed, 11 Dec 2013 16:02:41 +0100 (CET)
From:	Thomas Gleixner <tglx@...utronix.de>
To:	Ingo Molnar <mingo@...nel.org>
cc:	Peter Zijlstra <peterz@...radead.org>,
	Mike Galbraith <bitbucket@...ine.de>,
	Borislav Petkov <bp@...en8.de>, Len Brown <lenb@...nel.org>,
	Linux PM list <linux-pm@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Jeremy Eder <jeder@...hat.com>, x86@...nel.org
Subject: Re: 50 Watt idle power regression bisected to Linux-3.10

On Wed, 11 Dec 2013, Ingo Molnar wrote:
> 
> Another thing that is required I think is to issue a write barrier 
> before CLFLUSH instruction. By my (possibly incorrect ...) reading of 
> the documentation CLFLUSH does not appear to be ordered (at all), so 
> it might execute before the modification to the affected memory?

We already have a write barrier in the code which modifies
current_thread_info()->flags.
 
Thanks,

	tglx
--
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/