Re: [PATCH 1/2] perf tools: Fix seg fault with Intel PT

From: Arnaldo Carvalho de Melo
Date: Tue Jan 26 2016 - 09:30:38 EST


Em Tue, Jan 26, 2016 at 04:00:56PM +0200, Adrian Hunter escreveu:
> On 26/01/16 15:54, Arnaldo Carvalho de Melo wrote:
> > [acme@ssdandy linux]$

> > So, this needs:

> > 1) A machine that supports Intel PT
> > 2) A kernel that supports Intel PT
> > 3) A kernel that doesn't have perf_event_attr.context_switch, so that it tries
> > to use sched:sched_switch
> > 4) an unreadable tracefs

> > What was the kernel where you stumbled on this problem? What machine?

> Kernel was v4.2, machine was Broadwell.

> context_switch was added in v4.3 I think, and PT was v4.1
> so I guess v4.1 and v4.2 are affected.

Thanks for the info, my new main machine is a t450s, so Broadwell, will
boot with 4.1/4.2.

- Arnaldo