Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754709AbbDJJKv (ORCPT ); Fri, 10 Apr 2015 05:10:51 -0400 Received: from e28smtp05.in.ibm.com ([122.248.162.5]:58380 "EHLO e28smtp05.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754416AbbDJJKr (ORCPT ); Fri, 10 Apr 2015 05:10:47 -0400 Message-ID: <5527938B.1030901@linux.vnet.ibm.com> Date: Fri, 10 Apr 2015 14:40:35 +0530 From: Anshuman Khandual User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Michael Neuling CC: james.hogan@imgtec.com, avagin@openvz.org, Paul.Clothier@imgtec.com, linuxppc-dev@ozlabs.org, peterz@infradead.org, palves@redhat.com, davem@davemloft.net, shuahkh@osg.samsung.com, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, dhowells@redhat.com, Ulrich Weigand , kirjanov@gmail.com, oleg@redhat.com, davej@redhat.com, tglx@linutronix.de, sukadev@linux.vnet.ibm.com, Edjunior Barbosa Machado , sam.bobroff@au1.ibm.com Subject: Re: [V6,1/9] elf: Add new powerpc specifc core note sections References: <20141203052204.9DA8F1400DD@ozlabs.org> <547EB253.5050307@linux.vnet.ibm.com> <548578A8.5020901@linux.vnet.ibm.com> <54947C64.4030206@linux.vnet.ibm.com> <54A50094.5070902@linux.vnet.ibm.com> <1421883597.30744.3.camel@neuling.org> <1421963049.30744.23.camel@neuling.org> <1422419289.9646.20.camel@neuling.org> <1424667110.16027.6.camel@neuling.org> <1426718702.4866.2.camel@neuling.org> <1426719027.4866.4.camel@neuling.org> <550FEC36.8080803@linux.vnet.ibm.com> <1428534695.4682.18.camel@neuling.org> <55267595.9030202@linux.vnet.ibm.com> <1428635033.1554.49.camel@neuling.org> In-Reply-To: <1428635033.1554.49.camel@neuling.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable x-cbid: 15041009-0017-0000-0000-00000484089F Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2756 Lines: 59 On 04/10/2015 08:33 AM, Michael Neuling wrote: > On Thu, 2015-04-09 at 18:20 +0530, Anshuman Khandual wrote: >> On 04/09/2015 04:41 AM, Michael Neuling wrote: >>> On Wed, 2015-04-08 at 19:50 +0200, Ulrich Weigand wrote: >>>> Anshuman Khandual wrote on 23.03.2015 >>>> 11:34:30: >>>> >>>>>> With that in mind, do we have a way to set the top 32bits of the MSR >>>>>> (which contain the TM bits) when ptracing 32 bit processes? I can't >>>>>> find anything like that in this patch set. >>>>> >>>>> No, we dont have that yet. When ptracing in 32-bit mode the MSR value >>>>> which can be viewed or set from the user space through PTRACE_GETREGS >>>>> PTRACE_SETREGS call is it's lower 32 bits only. Either we can club >>>>> the upper 32 bits of MSR as part of one of the ELF core notes we are >>>>> adding in the patch series or we can create one more separate ELF core >>>>> note for that purpose. Let me know your opinion on this. >>>> >>>> I'm not sure I understand this. I thought we had the following: >>>> >>>> - If the process calling ptrace is itself 64-bit (which is how GDB is >>>> built on all current Linux distributions), then PTRACE_GETREGS etc. >>>> will *always* operate on 64-bit register sets, even if the target >>>> process is 32-bit. >>>> >>>> - If the process calling ptrace is 32-bit, then PTRACE_GETREGS will >>>> operate on 32-bit register sets. However, there is a separate >>>> PTRACE_GETREGS64 / PTRACE_SETREGS64 call that will also provide >>>> the opportunity to operate on the full 64-bit register set. Both >>>> apply independently of whether the target process is 32-bit or >>>> 64-bit. >>>> >>>> Is this not correct? >>> >>> I think you're correct. We should be right. I'd forgotten about the >>> GET/SETREGS64 interfaces. >> >> In that case, is the patch series complete and okay ? Is there any thing >> else we need to verify other than waiting for the GDB test results which >> Edjunior has been working on. But I am not aware of the status on the GDB >> test development front. > > I think we are good. I had posted a newer version [V7] of this patch series couple of months back which got ignored while the discussion continued in this version. V7: https://lkml.org/lkml/2015/1/14/19 Apart from the last gitignore related patch which already got merged into mainline separately, all other patches should be as good even today. I will try rebasing the series, running the base tests again and re post it in some time. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/