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Date:   Mon, 16 Nov 2020 14:29:20 -0300
From:   Arnaldo Carvalho de Melo <acme@kernel.org>
To:     Ian Rogers <irogers@google.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@redhat.com>,
        Namhyung Kim <namhyung@kernel.org>,
        linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com,
        Stephane Eranian <eranian@google.com>,
        Sandeep Dasgupta <sdasgup@google.com>
Subject: Re: [PATCH] perf test: Avoid an msan warning in a copied stack.
Message-ID: <20201116172920.GI509215@kernel.org>
References: <20201113182053.754625-1-irogers@google.com>
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Em Fri, Nov 13, 2020 at 10:20:53AM -0800, Ian Rogers escreveu:
> This fix is for a failure that occurred in the DWARF unwind perf test.
> Stack unwinders may probe memory when looking for frames. Memory
> sanitizer will poison and track uninitialized memory on the stack, and
> on the heap if the value is copied to the heap. This can lead to false
> memory sanitizer failures for the use of an uninitialized value. Avoid
> this problem by removing the poison on the copied stack.
> 
> The full msan failure with track origins looks like:



Thanks, applied.

- Arnaldo