[Linuxarm] Re: [PATCH for-next 1/2] RDMA/hns: Support query information of functions from FW

On 2021/3/24 3:56, Jason Gunthorpe wrote:

On Fri, Mar 12, 2021 at 05:48:26PM +0800, Weihang Li wrote:

...

+static int hns_roce_query_func_info(struct hns_roce_dev *hr_dev) +{

• struct hns_roce_pf_func_info *resp;
• struct hns_roce_cmq_desc desc;
• int ret;
• if (hr_dev->pci_dev->revision < PCI_REVISION_ID_HIP09)

• return 0;
  

• hns_roce_cmq_setup_basic_desc(&desc, HNS_ROCE_OPC_QUERY_FUNC_INFO,

• 		      true);
  

• ret = hns_roce_cmq_send(hr_dev, &desc, 1);
• if (ret)

• return ret;
  

• resp = (struct hns_roce_pf_func_info *)desc.data;

WTF is this cast?

struct hns_roce_cmq_desc { __le16 opcode; __le16 flag; __le16 retval; __le16 rsv; __le32 data[6]; };

Casting __le32 to a pointer is wrong

Jason

Hi Jason

desc.data is the address of array 'data[6]', it is got from the firmware, we cast it to 'struct hns_roce_pf_func_info *' to parse its contents. I think this is a cast from '__le32 *' to 'struct hns_roce_pf_func_info *'.

Thanks Weihang