linux-kernel - Re: [patch 07/11] x86/perf/uncore: Track packages not per cpu data

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: <20160218095134.GR6357@twins.programming.kicks-ass.net>
Date:	Thu, 18 Feb 2016 10:51:34 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	Stephane Eranian <eranian@...gle.com>
Cc:	Andi Kleen <andi@...stfloor.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	LKML <linux-kernel@...r.kernel.org>,
	Ingo Molnar <mingo@...nel.org>, Borislav Petkov <bp@...en8.de>,
	Harish Chegondi <harish.chegondi@...el.com>,
	Kan Liang <kan.liang@...el.com>,
	Andi Kleen <andi.kleen@...el.com>
Subject: Re: [patch 07/11] x86/perf/uncore: Track packages not per cpu data

On Thu, Feb 18, 2016 at 01:35:56AM -0800, Stephane Eranian wrote:
> But let's assume that the BIOS does some weird mappings and that the
> id for socket0 is indeed 0
> but for socket1 it is 255. Then doing:

Right, that would be fail. But Andi was talking about physical hotplug,
and that should work if the BIOS isn't weird like that.

Now obviously we cannot trust the BIOS to not be weird and tglx is
working on new topology bits that can indeed accommodate BIOS fail.

Would still be good to complain on boot if we find such weirdness, even
if its not fatal anymore.