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Date:   Thu, 12 Oct 2023 15:27:43 +0300
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Subject: Re: [PATCH v1] perf intel-pt: pkt-decoder: Fix alignment issues
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To:     Ian Rogers <irogers@google.com>, Namhyung Kim <namhyung@kernel.org>
Cc:     Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Jiri Olsa <jolsa@kernel.org>, Miguel Ojeda <ojeda@kernel.org>,
        Liam Howlett <liam.howlett@oracle.com>,
        linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org
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From:   Adrian Hunter <adrian.hunter@intel.com>
Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki,
 Business Identity Code: 0357606 - 4, Domiciled in Helsinki
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On 11/10/23 09:50, Ian Rogers wrote:
> On Tue, Oct 10, 2023 at 10:56 PM Namhyung Kim <namhyung@kernel.org> wrote:
>>
>> On Mon, Oct 9, 2023 at 8:31 AM Ian Rogers <irogers@google.com> wrote:
>>>
>>> On Sun, Oct 8, 2023 at 10:29 PM Namhyung Kim <namhyung@kernel.org> wrote:
>>>>
>>>> On Thu, Oct 5, 2023 at 2:24 PM Ian Rogers <irogers@google.com> wrote:
>>>>>
>>>>> On Thu, Oct 5, 2023 at 12:06 PM Adrian Hunter <adrian.hunter@intel.com> wrote:
>>>>>>
>>>>>> On 5/10/23 18:48, Ian Rogers wrote:
>>>>>>> On Mon, Oct 2, 2023 at 3:19 PM Ian Rogers <irogers@google.com> wrote:
>>>>>>>>
>>>>>>>> The byte aligned buffer is cast to large types and dereferenced
>>>>>>>> causing misaligned pointer warnings from undefined behavior sanitizer.
>>>>>>>> Fix the alignment issues with memcpy which may require the
>>>>>>>> introduction of temporaries.
>>>>>>>>
>>>>>>>> Signed-off-by: Ian Rogers <irogers@google.com>
>>>>>>>> ---
>>>>>>>
>>>>>>> This is a relatively small change that fixes building with
>>>>>>> -fsanitize=alignment -fsanitize-undefined-trap-on-error. Adrian, as
>>>>>>> this is Intel-PT could you take a look?
>>>>>>
>>>>>> Thanks! This has been down my list of things to do for ages,
>>>>>> but using get_unaligned_le16() etc seems nicer.  I sent a patch
>>>>>> set for that.
>>>>>
>>>>> Thanks Adrian! Your patch set looks good and I think after Arnaldo's
>>>>> comment is addressed we should go with it.
>>>>
>>>> I think it can be done as a later step as long as the interface is the
>>>> same.  Can I add your Ack's to the Adrian's patchset?
>>>
>>> I think addressing Arnaldo's comment:
>>> https://lore.kernel.org/lkml/ZR8QnasisGEsaaDR@kernel.org/
>>> will need some changes to the patch series, and so I was waiting to
>>> see the outcome of that.
>>
>> It seems it's done without further changes.  Can I get your Ack's now?
> 
> With the unaligned.h patch on its own, I think patch 1 of 5 needs
> dropping. For the rest I'm happy to acked-by.

The new patch is on top of the others, so patch 1 is still needed.