Re: stable-rc/linux-5.4.y bisection: baseline.dmesg.alert on meson-g12a-x96-max

From: Guillaume Tucker
Date: Fri May 01 2020 - 07:57:36 EST

Please see the bisection report below about a kernel Oops.

Reports aren't automatically sent to the public while we're
trialing new bisection features on kernelci.org but this one
looks valid.

The log shows a kernel NULL pointer dereference:

https://storage.kernelci.org/stable-rc/linux-5.4.y/v5.4.36-52-g35bbc55d9e29/arm64/defconfig/gcc-8/lab-baylibre/baseline-meson-g12a-x96-max.html#L1113

The call stack is not the same as in the commit message found by
the bisection, so maybe it only fixed part of the problem:

<1>[ 16.007376] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
<1>[ 16.016300] Mem abort info:
<1>[ 16.019269] ESR = 0x96000006
<1>[ 16.022571] EC = 0x25: DABT (current EL), IL = 32 bits
<1>[ 16.028075] SET = 0, FnV = 0
<1>[ 16.031356] EA = 0, S1PTW = 0
<1>[ 16.034705] Data abort info:
<1>[ 16.037837] ISV = 0, ISS = 0x00000006
<1>[ 16.041876] CM = 0, WnR = 0
<1>[ 16.045128] user pgtable: 4k pages, 48-bit VAs, pgdp=00000000be0f0000
<1>[ 16.051702] [0000000000000010] pgd=00000000be117003, pud=00000000be118003, pmd=0000000000000000
<0>[ 16.051709] Internal error: Oops: 96000006 [#1] PREEMPT SMP
<4>[ 16.133466] CPU: 2 PID: 33 Comm: kworker/2:1 Tainted: G W 5.4.37-rc1 #1
<4>[ 16.141566] Hardware name: Shenzhen Amediatech Technology Co., Ltd X96 Max (DT)
<4>[ 16.149087] Workqueue: events deferred_probe_work_func
<4>[ 16.154419] pstate: 20000005 (nzCv daif -PAN -UAO)
<4>[ 16.159428] pc : snd_soc_dapm_new_dai+0x3c/0x1b0
<4>[ 16.164252] lr : snd_soc_dapm_connect_dai_link_widgets+0x114/0x268
<4>[ 16.256970] Call trace:
<4>[ 16.259647] snd_soc_dapm_new_dai+0x3c/0x1b0
<4>[ 16.264129] snd_soc_dapm_connect_dai_link_widgets+0x114/0x268
<4>[ 16.270167] snd_soc_instantiate_card+0x858/0xb88
<4>[ 16.275083] snd_soc_register_card+0xf8/0x120
<4>[ 16.279656] devm_snd_soc_register_card+0x40/0x90
<4>[ 16.284575] axg_card_probe+0x9dc/0xaf0 [snd_soc_meson_axg_sound_card]
<4>[ 16.291299] platform_drv_probe+0x50/0xa0
<4>[ 16.295524] really_probe+0xd4/0x328
<4>[ 16.299319] driver_probe_device+0x54/0xe8
...


Guillaume


On 01/05/2020 10:32, kernelci.org bot wrote:
> * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
> * This automated bisection report was sent to you on the basis *
> * that you may be involved with the breaking commit it has *
> * found. No manual investigation has been done to verify it, *
> * and the root cause of the problem may be somewhere else. *
> * *
> * If you do send a fix, please include this trailer: *
> * Reported-by: "kernelci.org bot" <bot@xxxxxxxxxxxx> *
> * *
> * Hope this helps! *
> * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
>
> stable-rc/linux-5.4.y bisection: baseline.dmesg.alert on meson-g12a-x96-max
>
> Summary:
> Start: 35bbc55d9e296 Linux 5.4.37-rc1
> Plain log: https://storage.kernelci.org/stable-rc/linux-5.4.y/v5.4.36-52-g35bbc55d9e29/arm64/defconfig/gcc-8/lab-baylibre/baseline-meson-g12a-x96-max.txt
> HTML log: https://storage.kernelci.org/stable-rc/linux-5.4.y/v5.4.36-52-g35bbc55d9e29/arm64/defconfig/gcc-8/lab-baylibre/baseline-meson-g12a-x96-max.html
> Result: 09f4294793bd3 ASoC: meson: axg-card: fix codec-to-codec link setup
>
> Checks:
> revert: PASS
> verify: PASS
>
> Parameters:
> Tree: stable-rc
> URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
> Branch: linux-5.4.y
> Target: meson-g12a-x96-max
> CPU arch: arm64
> Lab: lab-baylibre
> Compiler: gcc-8
> Config: defconfig
> Test case: baseline.dmesg.alert
>
> Breaking commit found:
>
> -------------------------------------------------------------------------------
> commit 09f4294793bd3e70d68fdab5b392dff18bff62ca
> Author: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
> Date: Mon Apr 20 13:45:10 2020 +0200
>
> ASoC: meson: axg-card: fix codec-to-codec link setup
>
> commit 1164284270779e1865cc2046a2a01b58a1e858a9 upstream.
>
> Since the addition of commit 9b5db059366a ("ASoC: soc-pcm: dpcm: Only allow
> playback/capture if supported"), meson-axg cards which have codec-to-codec
> links fail to init and Oops:
>
> Unable to handle kernel NULL pointer dereference at virtual address 0000000000000128
> Internal error: Oops: 96000044 [#1] PREEMPT SMP
> CPU: 3 PID: 1582 Comm: arecord Not tainted 5.7.0-rc1
> pc : invalidate_paths_ep+0x30/0xe0
> lr : snd_soc_dapm_dai_get_connected_widgets+0x170/0x1a8
> Call trace:
> invalidate_paths_ep+0x30/0xe0
> snd_soc_dapm_dai_get_connected_widgets+0x170/0x1a8
> dpcm_path_get+0x38/0xd0
> dpcm_fe_dai_open+0x70/0x920
> snd_pcm_open_substream+0x564/0x840
> snd_pcm_open+0xfc/0x228
> snd_pcm_capture_open+0x4c/0x78
> snd_open+0xac/0x1a8
> ...
>
> While initiliazing the links, ASoC treats the codec-to-codec links of this
> card type as a DPCM backend. This error eventually leads to the Oops.
>
> Most of the card driver code is shared between DPCM backends and
> codec-to-codec links. The property "no_pcm" marking DCPM BE was left set on
> codec-to-codec links, leading to this problem. This commit fixes that.
>
> Fixes: 0a8f1117a680 ("ASoC: meson: axg-card: add basic codec-to-codec link support")
> Signed-off-by: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
> Link: https://lore.kernel.org/r/20200420114511.450560-2-jbrunet@xxxxxxxxxxxx
> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
>
> diff --git a/sound/soc/meson/axg-card.c b/sound/soc/meson/axg-card.c
> index 1f698adde506c..2b04ac3d8fd3b 100644
> --- a/sound/soc/meson/axg-card.c
> +++ b/sound/soc/meson/axg-card.c
> @@ -586,8 +586,10 @@ static int axg_card_add_link(struct snd_soc_card *card, struct device_node *np,
>
> if (axg_card_cpu_is_tdm_iface(dai_link->cpus->of_node))
> ret = axg_card_parse_tdm(card, np, index);
> - else if (axg_card_cpu_is_codec(dai_link->cpus->of_node))
> + else if (axg_card_cpu_is_codec(dai_link->cpus->of_node)) {
> dai_link->params = &codec_params;
> + dai_link->no_pcm = 0; /* link is not a DPCM BE */
> + }
>
> return ret;
> }
> -------------------------------------------------------------------------------
>
>
> Git bisection log:
>
> -------------------------------------------------------------------------------
> git bisect start
> # good: [aa73bcc376865c23e61dcebd467697b527901be8] Linux 5.4.36
> git bisect good aa73bcc376865c23e61dcebd467697b527901be8
> # bad: [35bbc55d9e296d37cf01555d415338b84a70d4c5] Linux 5.4.37-rc1
> git bisect bad 35bbc55d9e296d37cf01555d415338b84a70d4c5
> # bad: [924f1d37852ff357658c205dd114c70862865fc9] svcrdma: Fix trace point use-after-free race
> git bisect bad 924f1d37852ff357658c205dd114c70862865fc9
> # good: [b848f65436665b5fe675fd3f645c1a458e49f60a] counter: 104-quad-8: Add lock guards - generic interface
> git bisect good b848f65436665b5fe675fd3f645c1a458e49f60a
> # bad: [04b53ed855129c1703d00d8494e4c61309714a99] drivers: soc: xilinx: fix firmware driver Kconfig dependency
> git bisect bad 04b53ed855129c1703d00d8494e4c61309714a99
> # good: [ae886eae0318c71a6125347d6810a1578a83d262] ASoC: tas571x: disable regulators on failed probe
> git bisect good ae886eae0318c71a6125347d6810a1578a83d262
> # bad: [2c0990070379284dda0b51304ce19c2b96e083a2] ASoC: wm8960: Fix wrong clock after suspend & resume
> git bisect bad 2c0990070379284dda0b51304ce19c2b96e083a2
> # bad: [09f4294793bd3e70d68fdab5b392dff18bff62ca] ASoC: meson: axg-card: fix codec-to-codec link setup
> git bisect bad 09f4294793bd3e70d68fdab5b392dff18bff62ca
> # first bad commit: [09f4294793bd3e70d68fdab5b392dff18bff62ca] ASoC: meson: axg-card: fix codec-to-codec link setup
> -------------------------------------------------------------------------------
>