Re: [alsa-devel] [PATCH] ASoC: soc-core: Fix null pointer dereference in soc_find_component

From: Pierre-Louis Bossart
Date: Tue Jan 15 2019 - 16:17:01 EST



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.