Re: [PATCH v4] ACPI/IORT: Fix PMCG node single ID mapping handling.

[Tuan Phan]

> On May 20, 2020, at 5:58 AM, Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> wrote:
> 
> On Fri, May 15, 2020 at 12:24:46PM -0700, Tuan Phan wrote:
>> An IORT PMCG node can have no ID mapping if its overflow interrupt is
>> wire based therefore the code that parses the PMCG node can not assume
>> the node will always have a single mapping present at index 0.
>> 
>> Fix iort_get_id_mapping_index() by checking for an overflow interrupt
>> and mapping count.
>> 
>> Fixes: 24e516049360 ("ACPI/IORT: Add support for PMCG").
> 
> Remove these periods in the $SUBJECT and commit references, I
> don't know why you keep adding them.
> 
> Anyway - I don't know if it is too late for v5.8 but this patch
> is ready to be merged (minus the nits I have just mentioned).

Thanks, will fix it.
> 
> Lorenzo
> 
>> Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
>> Reviewed-by: Hanjun Guo <guoahanjun@xxxxxxxxxx>
>> Signed-off-by: Tuan Phan <tuanphan@xxxxxxxxxxxxxxxxxxxxxx>
>> ---
>> v1 -> v2:
>> - Use pmcg node to detect wired base overflow interrupt.
>> 
>> v2 -> v3:
>> - Address Hanjun and Robin's comments.
>> 
>> v3 -> v4:
>> - Update the title and description as mentioned by Lorenzo.
>> 
>> drivers/acpi/arm64/iort.c | 5 +++++
>> 1 file changed, 5 insertions(+)
>> 
>> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
>> index ed3d2d1..12bb70e 100644
>> --- a/drivers/acpi/arm64/iort.c
>> +++ b/drivers/acpi/arm64/iort.c
>> @@ -414,6 +414,7 @@ static struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node,
>> static int iort_get_id_mapping_index(struct acpi_iort_node *node)
>> {
>> 	struct acpi_iort_smmu_v3 *smmu;
>> +	struct acpi_iort_pmcg *pmcg;
>> 
>> 	switch (node->type) {
>> 	case ACPI_IORT_NODE_SMMU_V3:
>> @@ -441,6 +442,10 @@ static int iort_get_id_mapping_index(struct acpi_iort_node *node)
>> 
>> 		return smmu->id_mapping_index;
>> 	case ACPI_IORT_NODE_PMCG:
>> +		pmcg = (struct acpi_iort_pmcg *)node->node_data;
>> +		if (pmcg->overflow_gsiv || node->mapping_count == 0)
>> +			return -EINVAL;
>> +
>> 		return 0;
>> 	default:
>> 		return -EINVAL;
>> -- 
>> 2.7.4
>>