From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754148AbcCAXt4 (ORCPT ); Tue, 1 Mar 2016 18:49:56 -0500 Received: from mga14.intel.com ([192.55.52.115]:15065 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753702AbcCAXty (ORCPT ); Tue, 1 Mar 2016 18:49:54 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,524,1449561600"; d="scan'208";a="927476472" Date: Tue, 1 Mar 2016 15:49:53 -0800 From: Andi Kleen To: Arnaldo Carvalho de Melo Cc: Adrian Hunter , Andi Kleen , jolsa@kernel.org, namhyung@kernel.org, alexander.shishkin@intel.com, linux-kernel@vger.kernel.org Subject: Re: Intel PT not work on 4.5-rc6 as well after suspend/resume assembler Message-ID: <20160301234953.GD23621@tassilo.jf.intel.com> References: <1456533128-28381-1-git-send-email-andi@firstfloor.org> <1456533128-28381-2-git-send-email-andi@firstfloor.org> <20160229145625.GB32719@kernel.org> <20160229173528.GP5083@two.firstfloor.org> <20160229192549.GA3170@kernel.org> <20160301153524.GD3170@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160301153524.GD3170@kernel.org> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 01, 2016 at 12:35:24PM -0300, Arnaldo Carvalho de Melo wrote: > Em Mon, Feb 29, 2016 at 04:25:49PM -0300, Arnaldo Carvalho de Melo escreveu: > > Em Mon, Feb 29, 2016 at 06:35:28PM +0100, Andi Kleen escreveu: > > > > What kernel have you used for testing this? 4.5-rc? I'm having trouble > > > > with intel_pt with 4.5.0-rc4 :-\ > > > > Works for me (on -rc5). What problem do you see? > > > Doesn't work for me on (4.5.0-rc4), but after your report of it working > > my -rc4 .config and built -rc6+ with it, now it seems to work as > > expected, will test your patch with it later. > > Humm, after suspend/resume it is back not working, using your example > for this case: Hi Arnaldo, PT is always disabled when VT-x is active. I guess the problem is here that it doesn't get reenabled when context switching out of the guest. Need to add some code to KVM to do this (similar to how PEBS is handled) However it should work again when you stop the KVM guest and restart the trace. -Andi