linux-kernel - Re: [PATCH v1 00/11] perf script: Refactor branch flags for Arm SPE

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]

Message-ID: <Z62DOPuDJ-PrcHQw@google.com>
Date: Wed, 12 Feb 2025 21:29:28 -0800
From: Namhyung Kim <namhyung@...nel.org>
To: Ian Rogers <irogers@...gle.com>
Cc: Leo Yan <leo.yan@....com>, Arnaldo Carvalho de Melo <acme@...nel.org>,
	Mark Rutland <mark.rutland@....com>,
	Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
	Jiri Olsa <jolsa@...nel.org>,
	Adrian Hunter <adrian.hunter@...el.com>,
	"Liang, Kan" <kan.liang@...ux.intel.com>,
	John Garry <john.g.garry@...cle.com>, Will Deacon <will@...nel.org>,
	James Clark <james.clark@...aro.org>,
	Mike Leach <mike.leach@...aro.org>,
	linux-perf-users@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	Graham Woodward <graham.woodward@....com>
Subject: Re: [PATCH v1 00/11] perf script: Refactor branch flags for Arm SPE

On Wed, Feb 12, 2025 at 08:14:48AM -0800, Ian Rogers wrote:
> On Wed, Feb 12, 2025 at 12:54 AM Leo Yan <leo.yan@....com> wrote:
> >
> > Hi Ian,
> >
> > On Tue, Feb 11, 2025 at 02:34:46PM -0800, Ian Rogers wrote:
> > > On Wed, Feb 5, 2025 at 4:16 AM Leo Yan <leo.yan@....com> wrote:
> > > >
> > > > This patch series refactors branch flags for support Arm SPE.  The patch
> > > > set is divided into two parts, the first part is for refactoring common
> > > > code and the second part is for enabling Arm SPE.
> >
> > [...]
> > >
> > > Reviewed-by: Ian Rogers <irogers@...gle.com>
> > >
> > > Built and tested (on x86). A little strange patch 5 adds a new bit not
> > > at the end, but "Sample parsing" test wasn't broken so looks like it
> > > is good. I was surprised the use of value in the union:
> > > ```
> > > struct branch_flags {
> > > union {
> > > u64 value;
> > > struct {
> > > u64 mispred:1;
> > > u64 predicted:1;
> > > ...
> > > ```
> > > didn't get broken. Perhaps there's an opportunity for additional tests.

Probably because it just checks the value as a whole u64, not each
bitfield.  But it seems to test if the value of the input sample data
and synthesized-and-parsed output sample data is same.  So it may not be
important what value it has.

Anyway it'd be nice if any ARM folks can review this series.

Thanks,
Namhyung