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Subject: Re: [alsa-devel] [PATCH] ASoC: soc-core: Fix null pointer dereference
 in soc_find_component
To:     Matthias Reichl <hias@horus.com>, Mark Brown <broonie@kernel.org>,
        rohkumar@qti.qualcomm.com, alsa-devel@alsa-project.org,
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        Liam Girdwood <liam.r.girdwood@linux.intel.com>,
        srinivas.kandagatla@linaro.org,
        Rohit kumar <rohitkr@codeaurora.org>, asishb@codeaurora.org,
        Ajit Pandey <ajitp@codeaurora.org>
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From:   Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
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Date:   Tue, 15 Jan 2019 15:16:57 -0600
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>> Beyond the fact that the platform_name seems to be totally useless,
>> additional tests show that the patch ('ASoC: soc-core: defer card probe
>> until all component is added to list') adds a new restriction which
>> contradicts existing error checks.
>>
>> None of the Intel machine drivers set the dailink "cpu_name" field but use
>> the "cpu_dai_name" field instead. This was perfectly legit as documented by
>> the code at the end of soc_init_dai_link()
> This should be fixed by the patch
> "ASoC: core: Don't defer probe on optional, NULL components" which Mark
> already applied to his tree. See
> http://mailman.alsa-project.org/pipermail/alsa-devel/2019-January/144323.html

Ah yes, I missed this patch while I was debugging. Indeed this fixes the 
problem and my devices work again with Mark's for-next branch. Thanks 
Matthias!

>
> Maybe the defer card probe logic needs to be extended to also check if
> dai_link_name had already been registered (either cpu or cpu_dai_name
> needs to be set), not 100% sure which problem the defer card probe patch
> was trying to solve.
same here, I don't get why the deferred probe stuff only deals with one 
of the two options.