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Date:   Fri, 4 Mar 2022 14:41:42 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Adrian Hunter <adrian.hunter@intel.com>
Cc:     Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Jiri Olsa <jolsa@redhat.com>, linux-kernel@vger.kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        kvm@vger.kernel.org, H Peter Anvin <hpa@zytor.com>,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Leo Yan <leo.yan@linaro.org>
Subject: Re: [PATCH V2 03/11] perf/x86: Add support for TSC in nanoseconds as
 a perf event clock
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References: <20220214110914.268126-1-adrian.hunter@intel.com>
 <20220214110914.268126-4-adrian.hunter@intel.com>
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On Mon, Feb 14, 2022 at 01:09:06PM +0200, Adrian Hunter wrote:
> Currently, when Intel PT is used within a VM guest, it is not possible to
> make use of TSC because perf clock is subject to paravirtualization.

Yeah, so how much of that still makes sense, or ever did? AFAIK the
whole pv_clock thing is utter crazy. Should we not fix that instead?