linux-kernel - Re: [PATCH 2/4] perf/x86/ibs: Use CPUID region helper

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: <20240422214503.GDZibaX4G2HWQgZuvH@fat_crate.local>
Date: Mon, 22 Apr 2024 23:45:03 +0200
From: Borislav Petkov <bp@...en8.de>
To: Robert Richter <rrichter@....com>
Cc: Dave Hansen <dave.hansen@...el.com>,
	Dave Hansen <dave.hansen@...ux.intel.com>,
	linux-kernel@...r.kernel.org, jgross@...e.com, tglx@...utronix.de,
	x86@...nel.org, Kim Phillips <kim.phillips@....com>,
	Robert Richter <rric@...nel.org>
Subject: Re: [PATCH 2/4] perf/x86/ibs: Use CPUID region helper

On Mon, Apr 22, 2024 at 11:30:24PM +0200, Robert Richter wrote:
> I mean the case where the cpuid leaf exists but IBS_CAPS_AVAIL is
> clear. That could be possible with some cpuid override e.g. in virt
> envs.

Until there is a valid use case, I don't care.

> Not on real hardware and if future systems not decide to enable IBS
> feature bit and clear IBS_CAPS_AVAIL, which could be a valid case IMO.

Then they get what they ordered and get to keep the pieces.

We don't support every insane configuration virt comes up with.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette