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Date: Mon, 22 Apr 2024 23:45:03 +0200
From: Borislav Petkov <bp@alien8.de>
To: Robert Richter <rrichter@amd.com>
Cc: Dave Hansen <dave.hansen@intel.com>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	linux-kernel@vger.kernel.org, jgross@suse.com, tglx@linutronix.de,
	x86@kernel.org, Kim Phillips <kim.phillips@amd.com>,
	Robert Richter <rric@kernel.org>
Subject: Re: [PATCH 2/4] perf/x86/ibs: Use CPUID region helper
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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