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Date:   Mon, 12 Jun 2023 14:23:41 -0300
From:   Arnaldo Carvalho de Melo <acme@kernel.org>
To:     Ian Rogers <irogers@google.com>
Cc:     John Garry <john.g.garry@oracle.com>,
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Subject: Re: [PATCH v2 26/26] perf hist: Fix srcline memory leak
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Em Mon, Jun 12, 2023 at 07:46:14AM -0700, Ian Rogers escreveu:
> On Mon, Jun 12, 2023 at 7:16 AM Arnaldo Carvalho de Melo
> <acme@kernel.org> wrote:
> >
> > Em Mon, Jun 12, 2023 at 11:13:59AM -0300, Arnaldo Carvalho de Melo escreveu:
> > > Em Thu, Jun 08, 2023 at 04:28:23PM -0700, Ian Rogers escreveu:
> > > > srcline isn't freed if it is SRCLINE_UNKNOWN. Avoid strduping in this
> > > > case as such strdups are redundant and leak memory.
> > >
> > > The patch is ok as its what the rest of the code is doing, i.e. strcmp()
> > > to check if a srcline is the unknown one, but how about the following
> > > patch on top of yours?
> >
> > [acme@quaco perf-tools-next]$ strings ~/bin/perf | grep '??:0'
> > ??:0
> > SRCLINE_UNKNOWN ((char *) "??:0")
> > [acme@quaco perf-tools-next]$
> 
> Agreed, the strcmps make me nervous as they won't distinguish heap
> from a global meaning we could end up with things like pointers to
> freed memory. The comparison with the global is always going to be
> same imo.
> 
> Acked-by: Ian Rogers <irogers@google.com>

Thanks, applied and added your Acked-by.

- Arnaldo