[PATCH] media: verisilicon: Additional fix for the crash when opening the driver

[Benjamin Gaignard]

Le 23/05/2023 à 18:25, Benjamin Gaignard a écrit :
> This fixes the following issue observed on Odroid-M1 board:
>
>   Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008
>   Mem abort info:
>   ...
>   Modules linked in: crct10dif_ce hantro_vpu snd_soc_simple_card snd_soc_simple_card_utils v4l2_vp9 v4l2_h264 rockchip_saradc v4l2_mem2mem videobuf2_dma_contig videobuf2_memops rtc_rk808 videobuf2_v4l2 industrialio_triggered_buffer rockchip_thermal dwmac_rk stmmac_platform stmmac videodev kfifo_buf display_connector videobuf2_common pcs_xpcs mc rockchipdrm analogix_dp dw_mipi_dsi dw_hdmi drm_display_helper panfrost drm_shmem_helper gpu_sched ip_tables x_tables ipv6
>   CPU: 3 PID: 176 Comm: v4l_id Not tainted 6.3.0-rc7-next-20230420 #13481
>   Hardware name: Hardkernel ODROID-M1 (DT)
>   pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
>   pc : hantro_try_fmt+0xa0/0x278 [hantro_vpu]
>   lr : hantro_try_fmt+0x94/0x278 [hantro_vpu]
>   ...
>   Call trace:
>    hantro_try_fmt+0xa0/0x278 [hantro_vpu]
>    hantro_set_fmt_out+0x3c/0x298 [hantro_vpu]
>    hantro_reset_raw_fmt+0x98/0x128 [hantro_vpu]
>    hantro_set_fmt_cap+0x240/0x254 [hantro_vpu]
>    hantro_reset_encoded_fmt+0x94/0xcc [hantro_vpu]
>    hantro_reset_fmts+0x18/0x38 [hantro_vpu]
>    hantro_open+0xd4/0x20c [hantro_vpu]
>    v4l2_open+0x80/0x120 [videodev]
>    chrdev_open+0xc0/0x22c
>    do_dentry_open+0x13c/0x48c
>    vfs_open+0x2c/0x38
>    path_openat+0x550/0x934
>    do_filp_open+0x80/0x12c
>    do_sys_openat2+0xb4/0x168
>    __arm64_sys_openat+0x64/0xac
>    invoke_syscall+0x48/0x114
>    el0_svc_common+0x100/0x120
>    do_el0_svc+0x3c/0xa8
>    el0_svc+0x40/0xa8
>    el0t_64_sync_handler+0xb8/0xbc
>    el0t_64_sync+0x190/0x194
>   Code: 97fc8a7f f940aa80 52864a61 72a686c1 (b9400800)
>   ---[ end trace 0000000000000000 ]---
>
> Fixes: db6f68b51e5c ("media: verisilicon: Do not set context src/dst formats in reset functions")
>
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard at collabora.com>
> ---

Diederick, Marek, Michael,
I have tested this patch on my boards and I see no regressions on
decoder part and no more crash when probing the encoder.
Could you test it on your side to confirm it is ok ?

Thorsten, I try/test regzbot commands, please tell me if it is correct.

#regzbot ^introduced db6f68b51e5c
#regzbot title media: verisilicon: null pointer dereference in try_fmt
#regzbot ignore-activity


>   drivers/media/platform/verisilicon/hantro_v4l2.c | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/platform/verisilicon/hantro_v4l2.c b/drivers/media/platform/verisilicon/hantro_v4l2.c
> index 835518534e3b..61cfaaf4e927 100644
> --- a/drivers/media/platform/verisilicon/hantro_v4l2.c
> +++ b/drivers/media/platform/verisilicon/hantro_v4l2.c
> @@ -397,10 +397,12 @@ hantro_reset_raw_fmt(struct hantro_ctx *ctx, int bit_depth)
>   	if (!raw_vpu_fmt)
>   		return -EINVAL;
>   
> -	if (ctx->is_encoder)
> +	if (ctx->is_encoder) {
>   		encoded_fmt = &ctx->dst_fmt;
> -	else
> +		ctx->vpu_src_fmt = raw_vpu_fmt;
> +	} else {
>   		encoded_fmt = &ctx->src_fmt;
> +	}
>   
>   	hantro_reset_fmt(&raw_fmt, raw_vpu_fmt);
>   	raw_fmt.width = encoded_fmt->width;