| Date | Wed, 22 Oct 2014 16:15:47 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH v5 11/20] x86: perf: Intel PT and LBR/BTS are mutually exclusive |
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On Mon, Oct 13, 2014 at 04:45:39PM +0300, Alexander Shishkin wrote: > Intel PT cannot be used at the same time as LBR or BTS and will cause a > general protection fault if they are used together. In order to avoid > fixing up GPs in the fast path, instead we use flags to indicate that > that one of these is in use so that the other avoids MSR access altogether. >
Yeah, don't like this. Like I've said many times before we should simply disallow creating PT events when there are LBR events and vice versa.
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