net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)

Hello Netanel Belgazal,

The patch 1738cd3ed342: "net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)" from Aug 10, 2016, leads to the following static checker warning:

drivers/net/ethernet/amazon/ena/ena_ethtool.c:459 ena_flow_hash_to_flow_type()
warn: bitwise AND condition is false here

drivers/net/ethernet/amazon/ena/ena_ethtool.c
454
455 static u32 ena_flow_hash_to_flow_type(u16 hash_fields) 456 {
457 u32 data = 0;
458
459 if (hash_fields & ENA_ADMIN_RSS_L2_DA)

                                  ^^^^^^^^^^^^^^^^^^^

This is zero.

   460                  data |= RXH_L2DA;
   461  
   462          if (hash_fields & ENA_ADMIN_RSS_L3_DA)
   463                  data |= RXH_IP_DST;
   464  
   465          if (hash_fields & ENA_ADMIN_RSS_L3_SA)
   466                  data |= RXH_IP_SRC;
   467  
   468          if (hash_fields & ENA_ADMIN_RSS_L4_DP)
   469                  data |= RXH_L4_B_2_3;
   470  
   471          if (hash_fields & ENA_ADMIN_RSS_L4_SP)
   472                  data |= RXH_L4_B_0_1;
   473  
   474          return data;
   475  }

regards,
dan carpenter

Hello Netanel Belgazal,

The patch 1738cd3ed342: "net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)" from Aug 10, 2016, leads to the following static checker warning:

	drivers/net/ethernet/amazon/ena/ena_com.c:1259 ena_com_destroy_io_cq()
	warn: struct type mismatch 'ena_admin_aq_destroy_cq_cmd vs ena_admin_aq_destroy_sq_cmd'

drivers/net/ethernet/amazon/ena/ena_com.c
1251 int ena_com_destroy_io_cq(struct ena_com_dev *ena_dev,
1252 struct ena_com_io_cq *io_cq)
1253 {
1254 struct ena_com_admin_queue *admin_queue = &ena_dev->admin_queue;

  1255          struct ena_admin_aq_destroy_cq_cmd destroy_cmd;
                                            ^
  1256          struct ena_admin_acq_destroy_cq_resp_desc destroy_resp;
  1257          int ret;
  1258  
  1259          memset(&destroy_cmd, 0x0, sizeof(struct ena_admin_aq_destroy_sq_cmd));
                                                                             ^

These struct names are a million characters long but there is one character in the middle which is different. See if you can spot which one it is.

Presumably this is a cut and paste error because I really doubt that you are really basically transcribing the entire works of William Shakespear every time you declare a variable. Why not just say:

		memset(&destroy, 0, sizeof(destroy));

That's better style and more future proof.

1260

regards,
dan carpenter

Hi Dan,

Thank you for reporting this bug.

I will submit a patch that switch all the memsets in the code to be

memset(&cmd, 0, sizeof(cmd));

Note:

ena_admin_aq_destroy_cq_cmd and ena_admin_aq_destroy_sq_cmd

have the same size, so this bug does not suppose to create any memory corruption on

platforms with the existing driver.

Regards,

Netanel

Dan,

Thank you for your report.

The values of enum ena_admin_flow_hash_fileds should be power of two values and not consecutive integers.

I'll send a patch that fix the enum.

Regards,

Netanel