Re: [PATCH] clk: sunxi-ng: v3s: Fix incorrect number of hw_clks.

From: Icenowy Zheng
Date: Tue Nov 12 2019 - 08:00:40 EST




ä 2019å11æ11æ GMT+08:00 äå8:39:36, Maxime Ripard <mripard@xxxxxxxxxx> åå:
>Hi,
>
>Thanks for your patch
>
>On Sat, Nov 09, 2019 at 03:19:09PM +0000, Tian Yunhao wrote:
>> The hws field of sun8i_v3s_hw_clks has only 74
>> members. However, the number specified by CLK_NUMBER
>> is 77 (= CLK_I2S0 + 1). This leads to runtime segmentation
>> fault that is not always reproducible.
>>
>> This patch adds a protective field [CLK_NUMBER] which ensures
>> ARRAY_SIZE(.hws) is always greater than .num, thus eliminates
>> this error.
>>
>> Signed-off-by: Yunhao Tian <t123yh@xxxxxxxxxxx>
>> ---
>> drivers/clk/sunxi-ng/ccu-sun8i-v3s.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/drivers/clk/sunxi-ng/ccu-sun8i-v3s.c
>b/drivers/clk/sunxi-ng/ccu-sun8i-v3s.c
>> index 5c779eec454b..de7fce7f32e6 100644
>> --- a/drivers/clk/sunxi-ng/ccu-sun8i-v3s.c
>> +++ b/drivers/clk/sunxi-ng/ccu-sun8i-v3s.c
>> @@ -617,6 +617,7 @@ static struct clk_hw_onecell_data
>sun8i_v3s_hw_clks = {
>> [CLK_AVS] = &avs_clk.common.hw,
>> [CLK_MBUS] = &mbus_clk.common.hw,
>> [CLK_MIPI_CSI] = &mipi_csi_clk.common.hw,
>> + [CLK_NUMBER] = NULL,
>> },
>> .num = CLK_NUMBER,
>> };
>> @@ -699,6 +700,7 @@ static struct clk_hw_onecell_data
>sun8i_v3_hw_clks = {
>> [CLK_AVS] = &avs_clk.common.hw,
>> [CLK_MBUS] = &mbus_clk.common.hw,
>> [CLK_MIPI_CSI] = &mipi_csi_clk.common.hw,
>> + [CLK_NUMBER] = NULL,
>> },
>> .num = CLK_NUMBER,
>
>I'd rather have the number of clocks (.num) being properly set.

However the maximum clock indices number is different on V3s and V3, because
on V3s the last clock is missing.

Should we define CLK_NUMBER_V3S here?

>
>Maxime