linux-kernel - Re: [PATCH] i386: add command line option "local_apic_timer_c2

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: <p73lkhg2l1b.fsf@bingen.suse.de>
Date:	29 Mar 2007 16:15:28 +0200
From:	Andi Kleen <andi@...stfloor.org>
To:	Len Brown <lenb@...nel.org>
Cc:	Linus Torvalds <torvalds@...ux-foundation.org>,
	william.morrow@....com, jordan.crouse@....com,
	Thomas Gleixner <tglx@...utronix.de>,
	Pavel Machek <pavel@....cz>, Ingo Molnar <mingo@...e.hu>,
	"Eric W. Biederman" <ebiederm@...ssion.com>,
	Nick Piggin <nickpiggin@...oo.com.au>,
	Mingming Cao <cmm@...ibm.com>, Adrian Bunk <bunk@...sta.de>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Michal Piotrowski <michal.k.k.piotrowski@...il.com>,
	Mariusz Kozlowski <m.kozlowski@...land.pl>,
	Oliver Pinter <oliver.pntr@...il.com>,
	Sid Boyce <g3vbv@...eyonder.co.uk>,
	Nick Piggin <npiggin@...e.de>,
	Jens Axboe <jens.axboe@...cle.com>,
	Thomas Renninger <trenn@...e.de>
Subject: Re: [PATCH] i386: add command line option "local_apic_timer_c2_ok"

Len Brown <lenb@...nel.org> writes:

> On an Intel processor, it seems that the safe and simple route
> is if the system exports C2 or deeper, don't use the LAPIC timer.
> (which is what 2.6.21-rc5 is doing as of this moment)
> We may be able to white-list some systems over time.

On AMD it is the same, except that there seems to be at least
one system that does C2 like things while only exporting C1.
That is why i proposed to check for a battery too -- if there is one
always disable it too.

-Andi
-
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/