Date: Wed, 26 Oct 2016 11:44:53 -0200
From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Krister Johansen <kjlx@templeofstupid.com>
Cc: Namhyung Kim <namhyung@kernel.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        =?iso-8859-1?Q?Fr=E9d=E9ric?= Weisbecker <fweisbec@gmail.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 perf/core] perf script: fix a use after free crash.
Message-ID: <20161026134453.GA4936@kernel.org>
References: <20161007022200.GB31113@sejong>
 <20161011092839.GC7837@templeofstupid.com>
 <20161026002010.GD2525@templeofstupid.com>
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Em Tue, Oct 25, 2016 at 05:20:10PM -0700, Krister Johansen escreveu:
> On Tue, Oct 11, 2016 at 02:28:39AM -0700, Krister Johansen wrote:
> > If dso__load_kcore frees all of the existing maps, but one has already
> > been attached to a callchain cursor node, then we can get a SIGSEGV in
> > any function that happens to try to use this invalid cursor.  Use the
> > existing map refcount mechanism to forestall cleanup of a map until the
> > cursor iterates past the node.
> 
> It has been a couple of weeks since I sent out v2 of this patch.  I
> understand that folks here have plenty of irons in the fire, but I
> wanted to double-check that nobody was waiting on me for additional
> information or changes.

It was a mix of waiting for more people to review it, or for Masami to
run its refcount debugger on it, ended up falling thru the cracks.

I'll try to process it now.

- Arnaldo