Re: [PATCH v7 10/11] qcomtee: enable TEE_IOC_SHM_ALLOC ioctl

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 8/14/25 12:24 AM, Amirreza Zarrabi wrote:
> 
> 
> On 8/13/2025 8:00 PM, Konrad Dybcio wrote:
>> On 8/13/25 2:35 AM, Amirreza Zarrabi wrote:
>>> Enable userspace to allocate shared memory with QTEE. Since
>>> QTEE handles shared memory as object, a wrapper is implemented
>>> to represent tee_shm as an object. The shared memory identifier,
>>> obtained through TEE_IOC_SHM_ALLOC, is transferred to the driver using
>>> TEE_IOCTL_PARAM_ATTR_TYPE_OBJREF_INPUT/OUTPUT.
>>>
>>> Tested-by: Neil Armstrong <neil.armstrong@linaro.org>
>>> Acked-by: Sumit Garg <sumit.garg@oss.qualcomm.com>
>>> Tested-by: Harshal Dev <quic_hdev@quicinc.com>
>>> Signed-off-by: Amirreza Zarrabi <amirreza.zarrabi@oss.qualcomm.com>
>>> ---
>>
>> [...]
>>
>>> +/* Mapping information format as expected by QTEE. */
>>> +struct qcomtee_mapping_info {
>>> +	u64 paddr;
>>> +	u64 len;
>>> +	u32 perms;
>>> +} __packed;
>>
>> Please use types with explicit endianness, e.g. __le32. I'm assuming
>> TZ will always be little-endian, regardless of the host OS
>>
> 
> I'm not entirely sure how this point is relevant. As I understand it,
> the core that populates this struct is the same one that accesses it in TZ.
> Your argument would absolutely make sense if the host and TZ were operating
> on different cores with distinct architectures -- such as one being
> little-endian and the other big-endian, which is not the case.

CONFIG_CPU_BIG_ENDIAN=y exists on arm64

Konrad