From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pierre-Louis Bossart Subject: Re: [alsa-devel] [PATCH] ASoC: soc-core: Fix null pointer dereference in soc_find_component Date: Fri, 11 Jan 2019 15:49:08 -0600 Message-ID: <4886ed21-65d2-159d-afcd-bb26dcde636e@linux.intel.com> References: <1547194442-1487-1-git-send-email-rohitkr@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Rohit kumar , plai@codeaurora.org, bgoswami@codeaurora.org, asishb@codeaurora.org, lgirdwood@gmail.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, rohkumar@qti.qualcomm.com, srinivas.kandagatla@linaro.org, vinod.koul@linaro.org Cc: Ajit Pandey , Liam Girdwood List-Id: alsa-devel@alsa-project.org > Thanks for the overnight fix. This update fixes the issue on my > Skylake XPS13 test device (blind testing since I don't understand what > the code does). > > Tested-by: Pierre-Louis Bossart I need to take this back, this set of changes (initial+fix) causes an error with our HDMI support [   17.437684] sof-audio sof-audio: created machine bxt-pcm512x [   17.585279] bxt-pcm512x bxt-pcm512x: ASoC: failed to init link iDisp1 [   17.585639] bxt-pcm512x bxt-pcm512x: snd_soc_register_card failed -517 Removing your changes restores the functionality Adding some traces I can see that the the platform name we use doesn't seem compatible with your logic. All the Intel boards used a constant platform name matching the PCI ID, see e.g. [1], which IIRC is used to bind components. Liam, do you recall in more details if this is really required? [1] https://elixir.bootlin.com/linux/latest/source/sound/soc/intel/boards/bxt_da7219_max98357a.c#L475 [   18.205812] plb: platform name sof-audio [   18.206059] plb: cpu_name (null) [   18.206234] plb: platform name 0000:00:0e.0 [   18.206459] plb: returning -EPROBE_DEFER 1 [   18.206686] bxt-pcm512x bxt-pcm512x: ASoC: failed to init link iDisp1 [   18.207054] bxt-pcm512x bxt-pcm512x: snd_soc_register_card failed -517 diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index cbafbdd02483..ae731212f82b 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -1133,11 +1133,15 @@ static int soc_init_dai_link(struct snd_soc_card *card,          * Defer card registration if platform dai component is not added to          * component list.          */ +       pr_err("plb: platform name %s\n", link->platform->name);         if (link->platform->of_node || link->platform->name)                 if (!soc_find_component(link->platform->of_node, link->platform->name)) -                       return -EPROBE_DEFER; +                 { +                         pr_err("plb: returning -EPROBE_DEFER 1\n"); +                         return -EPROBE_DEFER; +                 }         /*          * CPU device may be specified by either name or OF node, but          * can be left unspecified, and will be matched based on DAI @@ -1154,9 +1158,14 @@ static int soc_init_dai_link(struct snd_soc_card *card,          * Defer card registration if cpu dai component is not added to          * component list.          */ +       pr_err("plb: cpu_name %s\n", link->cpu_name);         if (link->cpu_of_node || link->cpu_name)                 if (!soc_find_component(link->cpu_of_node, link->cpu_name)) -                       return -EPROBE_DEFER; +                 { +                         pr_err("plb: returning -EPROBE_DEFER 2\n"); +                         return -EPROBE_DEFER; + +                 }         /*          * At least one of CPU DAI name or CPU device name/node must be