linux-kernel - Re: [PATCH] perf_events: fix ordering bug in perf_output

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Fri, 19 Mar 2010 01:14:40 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	Stephane Eranian <eranian@...gle.com>
Cc:	linux-kernel@...r.kernel.org, mingo@...e.hu, paulus@...ba.org,
	davem@...emloft.net, fweisbec@...il.com, robert.richter@....com,
	perfmon2-devel@...ts.sf.net, eranian@...il.com
Subject: Re: [PATCH] perf_events: fix ordering bug in perf_output_sample()

On Thu, 2010-03-18 at 22:29 +0100, Stephane Eranian wrote:
> On Thu, Mar 18, 2010 at 7:33 PM, Peter Zijlstra <peterz@...radead.org> wrote:
> > On Thu, 2010-03-18 at 14:42 +0200, Stephane Eranian wrote:
> >>       In order to parse a sample correctly based on the information
> >>       requested via sample_type, the kernel needs to save each component
> >>       in a known order. There is no type value saved with each component.
> >>       The current convention is that each component is saved according to
> >>       the order in enum perf_event_sample_format. But perf_output_sample()
> >>       was not completely following this convention, thereby making samples
> >>       impossible to parse without internal kernel knowledge.
> >>
> >>       This patch puts things in the right order.
> >
> > NAK, not so actually, its in the order specified in the
> > PERF_RECORD_SAMPLE comment.
> >
> And why is that order different than the one in the enum?

Because I tried to keep the simple elements before the complex ones, but
in any case its too late to change any ordering there now, as its ABI.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/