From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6DB27C54EBD for ; Thu, 12 Jan 2023 13:12:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230395AbjALNMe (ORCPT ); Thu, 12 Jan 2023 08:12:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53696 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231434AbjALNMc (ORCPT ); Thu, 12 Jan 2023 08:12:32 -0500 Received: from madras.collabora.co.uk (madras.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e5ab]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BC5C0117C for ; Thu, 12 Jan 2023 05:12:30 -0800 (PST) Received: from [192.168.1.100] (2-237-20-237.ip236.fastwebnet.it [2.237.20.237]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: kholk11) by madras.collabora.co.uk (Postfix) with ESMTPSA id A5C766602DB1; Thu, 12 Jan 2023 13:12:28 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1673529149; bh=zNCyUB8IygCoX91+kR/VDkps5yL+dHwC6lvPRwByyeg=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=jwdlxdoHAGabMlX51D0gKMZXVW/wxZl5Y8vv7MwLUAEiwbMIYIStZsmOiRgcel4w7 QOqL8AMNoZg+4QV42+ctU59QFjDAnjKJ5RQV9ZDlH6yrQKFJVsLOo0AiZoBEOgYdpY UDtqMq6km8gwb2s+PYWv3Asq+ot2vCS+1XcGUg7yJY5H2947R7m2bNzlK8gUVj2wan QIyDQrwLpDrtokgI22vMHnfyqwcOcWMi8YdG2QnGzljuOH250gB2116/YQk7++SKrC cXcOtcPzndnM/1NmGuGeCdroAH6cT/2n99dLAjoTSAUopBE7JsRRMaIFOc82OL3mSi NfSLV90q4vdHQ== Message-ID: <394ec60d-33c0-1386-9445-eb0c596cc46c@collabora.com> Date: Thu, 12 Jan 2023 14:12:25 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.6.0 Subject: Re: [PATCH] ASoC: SOF: sof-audio: Check snd_sof_widget pointer not NULL To: =?UTF-8?Q?P=c3=a9ter_Ujfalusi?= , pierre-louis.bossart@linux.intel.com Cc: lgirdwood@gmail.com, yung-chuan.liao@linux.intel.com, ranjani.sridharan@linux.intel.com, kai.vehmanen@linux.intel.com, daniel.baluta@nxp.com, broonie@kernel.org, perex@perex.cz, tiwai@suse.com, rander.wang@intel.com, sound-open-firmware@alsa-project.org, alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, kernel@collabora.com, wenst@chromium.org References: <20230112104542.115151-1-angelogioacchino.delregno@collabora.com> Content-Language: en-US From: AngeloGioacchino Del Regno In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Il 12/01/23 14:02, Péter Ujfalusi ha scritto: > Hi Angelo, > > On 12/01/2023 12:45, AngeloGioacchino Del Regno wrote: >> In function sof_unprepare_widgets_in_path(), check if swidget is >> actually not NULL, as the widget may not have been initialized at all. >> >> This commit solves the following kernel panic seen on MediaTek MT8195: >> >> [ 18.025215] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000014 >> [ 18.034266] Mem abort info: >> [ 18.037314] ESR = 0x0000000096000004 >> [ 18.041314] EC = 0x25: DABT (current EL), IL = 32 bits >> [ 18.046876] SET = 0, FnV = 0 >> [ 18.050180] EA = 0, S1PTW = 0 >> [ 18.053572] FSC = 0x04: level 0 translation fault >> [ 18.058700] Data abort info: >> [ 18.061832] ISV = 0, ISS = 0x00000004 >> [ 18.065919] CM = 0, WnR = 0 >> [ 18.069137] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000115495000 >> [ 18.075826] [0000000000000014] pgd=0000000000000000, p4d=0000000000000000 >> [ 18.082867] Internal error: Oops: 0000000096000004 [#1] SMP >> [ 18.088688] Modules linked in: af_alg qrtr btusb btrtl btintel btmtk btbcm bluetooth 8021q garp uvcvideo mrp stp ecdh_generic llc ecc videobuf2_vmalloc mt7921e mt7921_common mt76_connac_lib mt76 mac80211 snd_sof_ipc_msg_injector snd_sof_ipc_flood_test cfg80211 snd_sof_mt8195 mtk_adsp_common snd_sof_xtensa_dsp snd_sof_of panfrost rfkill snd_sof crct10dif_ce cros_ec_sensors cros_ec_lid_angle gpu_sched sbs_battery cros_usbpd_logger cros_ec_sensors_core hid_multitouch snd_sof_utils fuse ipv6 >> [ 18.132109] CPU: 5 PID: 657 Comm: wireplumber Tainted: G W 6.2.0-rc3-next-20230111+ #230 >> [ 18.141834] Hardware name: Acer Tomato (rev2) board (DT) >> [ 18.147392] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) >> [ 18.154600] pc : sof_unprepare_widgets_in_path.isra.0+0x28/0x10c [snd_sof] >> [ 18.161735] lr : sof_walk_widgets_in_order+0x198/0x1d0 [snd_sof] >> [ 18.167996] sp : ffff80000eb0b870 >> [ 18.171558] x29: ffff80000eb0b870 x28: 0000000000000001 x27: ffff5d8e178c4c00 >> [ 18.178939] x26: ffffbd50140fd758 x25: ffffbd50140fd760 x24: 0000000000000000 >> [ 18.186321] x23: 0000000000000000 x22: ffff5d8e109dd080 x21: ffff5d8e0a429280 >> [ 18.193702] x20: 0000000000000000 x19: ffff5d8e11fe4800 x18: 0000000000000000 >> [ 18.201083] x17: 0000000000000000 x16: ffffbd5073deabb0 x15: 0000000000000000 >> [ 18.208464] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 >> [ 18.215846] x11: 0000000000000000 x10: 0000000000002780 x9 : ffffbd50140eb4bc >> [ 18.223228] x8 : ffff5d8e1b5327e0 x7 : 0000000000000000 x6 : ffff5d8e1b530000 >> [ 18.230610] x5 : 0000000000000003 x4 : 0000000000000001 x3 : 0000000000000000 >> [ 18.237991] x2 : 0000000000000000 x1 : ffff5d8e11fe4800 x0 : ffff5d8e0a429280 >> [ 18.245372] Call trace: >> [ 18.248066] sof_unprepare_widgets_in_path.isra.0+0x28/0x10c [snd_sof] >> [ 18.254847] sof_walk_widgets_in_order+0x198/0x1d0 [snd_sof] >> [ 18.260760] sof_widget_list_free+0x7c/0xbc [snd_sof] >> [ 18.266066] sof_pcm_hw_free+0x10c/0x1c0 [snd_sof] >> [ 18.271110] snd_soc_pcm_component_hw_free+0x8c/0xe0 >> [ 18.276327] soc_pcm_hw_clean+0x60/0x11c >> [ 18.280498] dpcm_fe_dai_hw_free+0x98/0x110 >> [ 18.284930] snd_pcm_common_ioctl+0xc48/0x1a2c >> [ 18.289624] snd_pcm_ioctl+0x38/0x50 >> [ 18.293448] __arm64_sys_ioctl+0xb0/0xf4 >> [ 18.297620] invoke_syscall+0x50/0x120 >> [ 18.301618] el0_svc_common.constprop.0+0x17c/0x1b0 >> [ 18.306744] do_el0_svc+0x40/0xc4 >> [ 18.310307] el0_svc+0x48/0xf0 >> [ 18.313611] el0t_64_sync_handler+0xb8/0xc0 >> [ 18.318041] el0t_64_sync+0x1a0/0x1a4 >> [ 18.321953] Code: aa0103f3 f90013f5 aa0003f5 f9406834 (39405280) >> [ 18.328293] ---[ end trace 0000000000000000 ]--- >> >> Fixes: 9862dcf70245 ("ASoC: SOF: don't unprepare widget used other pipelines") >> Fixes: ce59804d2643 ("ASoC: SOF: clear prepare state when widget is unprepared") >> Signed-off-by: AngeloGioacchino Del Regno >> --- >> sound/soc/sof/sof-audio.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/sound/soc/sof/sof-audio.c b/sound/soc/sof/sof-audio.c >> index e1ab8380e7d8..1988717762b3 100644 >> --- a/sound/soc/sof/sof-audio.c >> +++ b/sound/soc/sof/sof-audio.c >> @@ -274,7 +274,7 @@ sof_unprepare_widgets_in_path(struct snd_sof_dev *sdev, struct snd_soc_dapm_widg >> struct snd_soc_dapm_path *p; >> >> /* return if the widget is in use or if it is already unprepared */ >> - if (!swidget->prepared || swidget->use_count > 1) >> + if (!swidget || !swidget->prepared || swidget->use_count > 1) >> return; > > we actually have a pending patch for upstream which did not yet made it > to the gate: > https://github.com/thesofproject/linux/commit/922646d533100044d95a050b222533d59f06020c > > It also adds symmetrical check for the prepare path. > > Would you be OK if I send that right away to replace your fix? > I didn't know that you had something similar - I've been carrying this patch locally for ~1.5 months, thinking that it was an issue with MediaTek drivers... ...but after investigating a bit (read: after I've found some time to actually investigate), it really looked like a more generic issue - for which reason I decided to send this patch upstream. Speaking of your patch: I think that the check that you've added to sof_prepare_widgets_in_path() will never trigger... at least, it's never been the case here, but that may be a platform-specific thing (even though I also have virtual widgets on MTK). Also, your patch misses the Fixes tags (and this fix shall be backported). Finally, I'd be OK with that if: 1. You add the Fixes tag for backporting; and 2. Describe why the swidget NULL check is required in sof_prepare_widgets_in_path() and why the legacy HDA machine driver would call that function with NULL swidget as that looks like a HDA driver bug, rather than a SOF core bug. Regards, Angelo