Re: [PATCH v3 07/20] cxl: harden resource_contains checks to handle zero size resources

Alejandro Lucero Palau
2024-09-16T12:37:49Z

On 9/13/24 18:36, Jonathan Cameron wrote:
> On Sat, 7 Sep 2024 09:18:23 +0100
> <alejandro.lucero-palau@amd.com> wrote:
>
>> From: Alejandro Lucero <alucerop@amd.com>
>>
>> For a resource defined with size zero, resource_contains returns
>> always true.
>>
>> Add resource size check before using it.
>>
>> Signed-off-by: Alejandro Lucero <alucerop@amd.com>
>> ---
>> drivers/cxl/core/hdm.c | 5 +++--
>> 1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c
>> index 3df10517a327..953a5f86a43f 100644
>> --- a/drivers/cxl/core/hdm.c
>> +++ b/drivers/cxl/core/hdm.c
>> @@ -327,10 +327,11 @@ static int __cxl_dpa_reserve(struct cxl_endpoint_decoder *cxled,
>> cxled->dpa_res = res;
>> cxled->skip = skipped;
>>
>> - if (resource_contains(&cxlds->pmem_res, res))
>> + if ((resource_size(&cxlds->pmem_res)) && (resource_contains(&cxlds->pmem_res, res))) {
> Excess brackets + I'd break that over two lines.

Right. I'll fix it.

Thanks

>
>> cxled->mode = CXL_DECODER_PMEM;
>> - else if (resource_contains(&cxlds->ram_res, res))
>> + } else if ((resource_size(&cxlds->ram_res)) && (resource_contains(&cxlds->ram_res, res))) {
> Same here,
>
>> cxled->mode = CXL_DECODER_RAM;
>> + }
>> else {
>> dev_warn(dev, "decoder%d.%d: %pr mixed mode not supported\n",
>> port->id, cxled->cxld.id, cxled->dpa_res);