Re: [PATCH v2 3/6] firmware: qcom: scm: Handle various probe ordering for qcom_scm_assign_mem()

[Krzysztof Kozlowski]

On 07/01/2025 01:42, Bjorn Andersson wrote:
>>
>> diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
>> index 5d91b8e22844608f35432f1ba9c08d477d4ff762..93212c8f20ad65ecc44804b00f4b93e3eaaf8d95 100644
>> --- a/drivers/firmware/qcom/qcom_scm.c
>> +++ b/drivers/firmware/qcom/qcom_scm.c
>> @@ -1075,6 +1075,9 @@ int qcom_scm_assign_mem(phys_addr_t mem_addr, size_t mem_sz,
>>  	int ret, i, b;
>>  	u64 srcvm_bits = *srcvm;
>>  
>> +	if (!qcom_scm_is_available())
>> +		return -EPROBE_DEFER;
> 
> This API is generally called from places other than probe, making the
> return of EPROBE_DEFER undesirable. While not pretty, a client depending
> on the scm driver to be probed is expected to call
> qcom_scm_is_available().
> 
> qcom_rmtfs_mem_probe() does this right before calling
> qcom_scm_assign_mem(), am I misunderstanding the case you're describing?

I tried to reproduce my NULL ptr but now I cannot and indeed if every
path is protected with qcom_scm_is_available() everything should be fine.

Let's skip this patch then.

Best regards,
Krzysztof