linux-kernel - Re: [PATCH 2/2] perf/tools: put new buildid locks to use

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

Message-ID: <20150514113821.GB1313@krava.redhat.com>
Date:	Thu, 14 May 2015 13:38:21 +0200
From:	Jiri Olsa <jolsa@...hat.com>
To:	Ingo Molnar <mingo@...nel.org>
Cc:	Milos Vyletel <milos@...hat.com>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	Paul Mackerras <paulus@...ba.org>,
	Ingo Molnar <mingo@...hat.com>,
	Arnaldo Carvalho de Melo <acme@...nel.org>,
	Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>,
	Namhyung Kim <namhyung@...nel.org>,
	Jiri Olsa <jolsa@...nel.org>, He Kuang <hekuang@...wei.com>,
	Adrian Hunter <adrian.hunter@...el.com>,
	"open list:PERFORMANCE EVENT..." <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 2/2] perf/tools: put new buildid locks to use

On Thu, May 14, 2015 at 12:40:59PM +0200, Ingo Molnar wrote:
> 
> * Milos Vyletel <milos@...hat.com> wrote:
> 
> > Use new read/write locks when accesing buildid directory on places where
> > we may race if multiple instances are run simultaneously.
> 
> Dunno, this will create locking interaction between multiple instances 
> of perf - hanging each other, etc.
> 
> And it seems unnecessary: the buildid hierarchy is already spread out. 
> What kind of races might there be?

there was just recently one fixed by commit:
  0635b0f71424 perf tools: Fix race in build_id_cache__add_s()

havent checked the final patch yet, but the idea is to
protect us from similar bugs

jirka
--
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/