Re: [PATCH] ASoC: Intel: kbl_rt5663_max98927: Fix kabylake_ssp_fixup function

[Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>]

On 10/14/20 9:16 AM, Tomasz Figa wrote:
> This is a copy of commit 5c5f1baee85a ("ASoC: Intel:
> kbl_rt5663_rt5514_max98927: Fix kabylake_ssp_fixup function") applied to
> the kbl_rt5663_max98927 board file.
> 
> Original explanation of the change:
> 
> kabylake_ssp_fixup function uses snd_soc_dpcm to identify the
> codecs DAIs. The HW parameters are changed based on the codec DAI of the
> stream. The earlier approach to get snd_soc_dpcm was using container_of()
> macro on snd_pcm_hw_params.
> 
> The structures have been modified over time and snd_soc_dpcm does not have
> snd_pcm_hw_params as a reference but as a copy. This causes the current
> driver to crash when used.
> 
> This patch changes the way snd_soc_dpcm is extracted. snd_soc_pcm_runtime
> holds 2 dpcm instances (one for playback and one for capture). 2 codecs
> on the SSP are dmic (capture) and speakers (playback). Based on the
> stream direction, snd_soc_dpcm is extracted from snd_soc_pcm_runtime.
> 
> Fixes a boot crash on a HP Chromebook x2:
> 
> [   16.582225] BUG: kernel NULL pointer dereference, address: 0000000000000050
> [   16.582231] #PF: supervisor read access in kernel mode
> [   16.582233] #PF: error_code(0x0000) - not-present page
> [   16.582234] PGD 0 P4D 0
> [   16.582238] Oops: 0000 [#1] PREEMPT SMP PTI
> [   16.582241] CPU: 0 PID: 1980 Comm: cras Tainted: G         C        5.4.58 #1
> [   16.582243] Hardware name: HP Soraka/Soraka, BIOS Google_Soraka.10431.75.0 08/30/2018
> [   16.582247] RIP: 0010:kabylake_ssp_fixup+0x19/0xbb [snd_soc_kbl_rt5663_max98927]
> [   16.582250] Code: c6 6f c5 80 c0 44 89 f2 31 c0 e8 3e c9 4c d6 eb de 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 53 48 89 f3 48 8b 46 c8 48 8b 4e d0 <48> 8b 49 10 4c 8b 78 10 4c 8b 31 4c 89 f7 48 c7 c6 4b c2 80 c0 e8
> [   16.582252] RSP: 0000:ffffaf7e81e0b958 EFLAGS: 00010282
> [   16.582254] RAX: ffffffff96f13e0d RBX: ffffaf7e81e0ba00 RCX: 0000000000000040
> [   16.582256] RDX: ffffaf7e81e0ba00 RSI: ffffaf7e81e0ba00 RDI: ffffa3b208558028
> [   16.582258] RBP: ffffaf7e81e0b970 R08: ffffa3b203b54160 R09: ffffaf7e81e0ba00
> [   16.582259] R10: 0000000000000000 R11: ffffffffc080b345 R12: ffffa3b209fb6e00
> [   16.582261] R13: ffffa3b1b1a47838 R14: ffffa3b1e6197f28 R15: ffffaf7e81e0ba00
> [   16.582263] FS:  00007eb3f25aaf80(0000) GS:ffffa3b236a00000(0000) knlGS:0000000000000000
> [   16.582265] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [   16.582267] CR2: 0000000000000050 CR3: 0000000246bc8006 CR4: 00000000003606f0
> [   16.582269] Call Trace:
> [   16.582275]  snd_soc_link_be_hw_params_fixup+0x21/0x68
> [   16.582278]  snd_soc_dai_hw_params+0x25/0x94
> [   16.582282]  soc_pcm_hw_params+0x2d8/0x583
> [   16.582288]  dpcm_be_dai_hw_params+0x172/0x29e
> [   16.582291]  dpcm_fe_dai_hw_params+0x9f/0x12f
> [   16.582295]  snd_pcm_hw_params+0x137/0x41c
> [   16.582298]  snd_pcm_hw_params_user+0x3c/0x71
> [   16.582301]  snd_pcm_common_ioctl+0x2c6/0x565
> [   16.582304]  snd_pcm_ioctl+0x32/0x36
> [   16.582307]  do_vfs_ioctl+0x506/0x783
> [   16.582311]  ksys_ioctl+0x58/0x83
> [   16.582313]  __x64_sys_ioctl+0x1a/0x1e
> [   16.582316]  do_syscall_64+0x54/0x7e
> [   16.582319]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> [   16.582322] RIP: 0033:0x7eb3f1886157
> [   16.582324] Code: 8a 66 90 48 8b 05 11 dd 2b 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 dc 2b 00 f7 d8 64 89 01 48
> [   16.582326] RSP: 002b:00007ffff7559818 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> [   16.582329] RAX: ffffffffffffffda RBX: 00005acc9188b140 RCX: 00007eb3f1886157
> [   16.582330] RDX: 00007ffff7559940 RSI: 00000000c2604111 RDI: 000000000000001e
> [   16.582332] RBP: 00007ffff7559840 R08: 0000000000000004 R09: 0000000000000000
> [   16.582333] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000bb80
> [   16.582335] R13: 00005acc91702e80 R14: 00007ffff7559940 R15: 00005acc91702e80
> [   16.582337] Modules linked in: rfcomm cmac algif_hash algif_skcipher af_alg uinput hid_google_hammer snd_soc_kbl_rt5663_max98927 snd_soc_hdac_hdmi snd_soc_dmic snd_soc_skl_ssp_clk snd_soc_skl snd_soc_sst_ipc snd_soc_sst_dsp snd_soc_hdac_hda snd_soc_acpi_intel_match snd_soc_acpi snd_hda_ext_core snd_intel_dspcfg snd_hda_codec snd_hwdep snd_hda_core ipu3_cio2 ipu3_imgu(C) videobuf2_v4l2 videobuf2_common videobuf2_dma_sg videobuf2_memops snd_soc_rt5663 snd_soc_max98927 snd_soc_rl6231 ov5670 ov13858 acpi_als v4l2_fwnode dw9714 fuse xt_MASQUERADE iio_trig_sysfs cros_ec_light_prox cros_ec_sensors cros_ec_sensors_core cros_ec_sensors_ring industrialio_triggered_buffer kfifo_buf industrialio cros_ec_sensorhub cdc_ether usbnet btusb btrtl btintel btbcm bluetooth ecdh_generic ecc lzo_rle lzo_compress iwlmvm zram iwl7000_mac80211 r8152 mii iwlwifi cfg80211 joydev
> [   16.584243] gsmi: Log Shutdown Reason 0x03
> [   16.584246] CR2: 0000000000000050
> [   16.584248] ---[ end trace c8511d090c11edff ]---
> 
> Suggested-by: Łukasz Majczak <lmajczak@google.com>
> Fixes: 2e5894d73789e ("ASoC: pcm: Add support for DAI multicodec")
> Signed-off-by: Tomasz Figa <tfiga@chromium.org>

Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>

Thanks!

> ---
>   sound/soc/intel/boards/kbl_rt5663_max98927.c | 39 ++++++++++++++++----
>   1 file changed, 31 insertions(+), 8 deletions(-)
> 
> diff --git a/sound/soc/intel/boards/kbl_rt5663_max98927.c b/sound/soc/intel/boards/kbl_rt5663_max98927.c
> index 3ea4602dfb3e..9a4b3d0973f6 100644
> --- a/sound/soc/intel/boards/kbl_rt5663_max98927.c
> +++ b/sound/soc/intel/boards/kbl_rt5663_max98927.c
> @@ -401,17 +401,40 @@ static int kabylake_ssp_fixup(struct snd_soc_pcm_runtime *rtd,
>   	struct snd_interval *chan = hw_param_interval(params,
>   			SNDRV_PCM_HW_PARAM_CHANNELS);
>   	struct snd_mask *fmt = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
> -	struct snd_soc_dpcm *dpcm = container_of(
> -			params, struct snd_soc_dpcm, hw_params);
> -	struct snd_soc_dai_link *fe_dai_link = dpcm->fe->dai_link;
> -	struct snd_soc_dai_link *be_dai_link = dpcm->be->dai_link;
> +	struct snd_soc_dpcm *dpcm, *rtd_dpcm = NULL;
> +
> +	/*
> +	 * The following loop will be called only for playback stream
> +	 * In this platform, there is only one playback device on every SSP
> +	 */
> +	for_each_dpcm_fe(rtd, SNDRV_PCM_STREAM_PLAYBACK, dpcm) {
> +		rtd_dpcm = dpcm;
> +		break;
> +	}
> +
> +	/*
> +	 * This following loop will be called only for capture stream
> +	 * In this platform, there is only one capture device on every SSP
> +	 */
> +	for_each_dpcm_fe(rtd, SNDRV_PCM_STREAM_CAPTURE, dpcm) {
> +		rtd_dpcm = dpcm;
> +		break;
> +	}
> +
> +	if (!rtd_dpcm)
> +		return -EINVAL;
> +
> +	/*
> +	 * The above 2 loops are mutually exclusive based on the stream direction,
> +	 * thus rtd_dpcm variable will never be overwritten
> +	 */
>   
>   	/*
>   	 * The ADSP will convert the FE rate to 48k, stereo, 24 bit
>   	 */
> -	if (!strcmp(fe_dai_link->name, "Kbl Audio Port") ||
> -	    !strcmp(fe_dai_link->name, "Kbl Audio Headset Playback") ||
> -	    !strcmp(fe_dai_link->name, "Kbl Audio Capture Port")) {
> +	if (!strcmp(rtd_dpcm->fe->dai_link->name, "Kbl Audio Port") ||
> +	    !strcmp(rtd_dpcm->fe->dai_link->name, "Kbl Audio Headset Playback") ||
> +	    !strcmp(rtd_dpcm->fe->dai_link->name, "Kbl Audio Capture Port")) {
>   		rate->min = rate->max = 48000;
>   		chan->min = chan->max = 2;
>   		snd_mask_none(fmt);
> @@ -421,7 +444,7 @@ static int kabylake_ssp_fixup(struct snd_soc_pcm_runtime *rtd,
>   	 * The speaker on the SSP0 supports S16_LE and not S24_LE.
>   	 * thus changing the mask here
>   	 */
> -	if (!strcmp(be_dai_link->name, "SSP0-Codec"))
> +	if (!strcmp(rtd_dpcm->be->dai_link->name, "SSP0-Codec"))
>   		snd_mask_set_format(fmt, SNDRV_PCM_FORMAT_S16_LE);
>   
>   	return 0;
>