2023-12-03 07:33:13

by Ayush Singh

[permalink] [raw]
Subject: Re: [PATCH] greybus: gb-beagleplay: fix restricted __le16 degrades to integer warning

I apologize for the late response (college exams were going on).

I will go through the driver to find if any other endianness fixes are
needed.

As for `hdlc_payload->len`, the whole `hdlc_payload` is an abstraction
to store array length with the actual pointer. The len is never actually
sent over HDLC, so it should be fine.


Ayush Singh

On 11/14/23 20:27, Alex Elder wrote:
> On 11/14/23 8:01 AM, Ayush Singh wrote:
>> greybus message header->size are of type __le16, so to fix this warnings
>> we are using le16_to_cpu() macros.
>
> This is more than a warning, it's a bug (though it has no
> effect with a little-endian native CPU).
>
> I suggest you add:
>
> Fixes: ec558bbfea671 ("greybus: Add BeaglePlay Linux Driver")
>
> Should your hdlc_payload->len field be defined as little-endian?
> I've only scanned through this file at this point but I'm thinking
> there might be other endianness fixes needed as well.
>
>                     -Alex
>
>
>
>>
>> Reported-by: kernel test robot <[email protected]>
>> Closes: https://lore.kernel.org/r/[email protected]/
>> Signed-off-by: Ayush Singh <[email protected]>
>> ---
>>   drivers/greybus/gb-beagleplay.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/greybus/gb-beagleplay.c
>> b/drivers/greybus/gb-beagleplay.c
>> index 43318c1993ba..b3f47b5cbbfa 100644
>> --- a/drivers/greybus/gb-beagleplay.c
>> +++ b/drivers/greybus/gb-beagleplay.c
>> @@ -344,7 +344,7 @@ static int gb_message_send(struct gb_host_device
>> *hd, u16 cport, struct gb_messa
>>       dev_dbg(&hd->dev, "Sending greybus message with Operation %u,
>> Type: %X on Cport %u",
>>           msg->header->operation_id, msg->header->type, cport);
>>   -    if (msg->header->size > RX_HDLC_PAYLOAD)
>> +    if (le16_to_cpu(msg->header->size) > RX_HDLC_PAYLOAD)
>>           return dev_err_probe(&hd->dev, -E2BIG, "Greybus message too
>> big");
>>         memcpy(msg->header->pad, &cport, sizeof(cport));
>