[PATCH v7] igb: Assign random MAC address instead of fail in case of invalid one

[Lixue Liang]

From: Lixue Liang <lianglixue@xxxxxxxxxxxxxxxx>

Add the module parameter "allow_invalid_mac_address" to control the
behavior. When set to true, a random MAC address is assigned, and the
driver can be loaded, allowing the user to correct the invalid MAC address.

Signed-off-by: Lixue Liang <lianglixue@xxxxxxxxxxxxxxxx>
---
Changelog:
* v7:
  - To group each parameter together
Suggested-by Tony Nguyen <anthony.l.nguyen@xxxxxxxxx>
* v6:
  - Modify commit messages and naming of module parameters
  - [PATCH v6] link:
    https://lore.kernel.org/netdev/20220610023922.74892-1-lianglixuehao@xxxxxxx/
Suggested-by Paul <pmenzel@xxxxxxxxxxxxx>
* v5:
  - Through the setting of module parameters, it is allowed to complete
    the loading of the igb network card driver with an invalid MAC address.
  - [PATCH v5] link:
    https://lore.kernel.org/netdev/20220609083904.91778-1-lianglixuehao@xxxxxxx/
Suggested-by <alexander.duyck@xxxxxxxxx>
* v4:
  - Change the igb_mian in the title to igb
  - Fix dev_err message: replace "already assigned random MAC address"
    with "Invalid MAC address. Assigned random MAC address"
  - [PATCH v4] link:
    https://lore.kernel.org/netdev/20220601150428.33945-1-lianglixuehao@xxxxxxx/
Suggested-by Tony <anthony.l.nguyen@xxxxxxxxx>

* v3:
  - Add space after comma in commit message
  - Correct spelling of MAC address
  - [PATCH v3] link:
    https://lore.kernel.org/netdev/20220530105834.97175-1-lianglixuehao@xxxxxxx/
Suggested-by Paul <pmenzel@xxxxxxxxxxxxx>

* v2:
  - Change memcpy to ether_addr_copy
  - Change dev_info to dev_err
  - Fix the description of the commit message
  - Change eth_random_addr to eth_hw_addr_random
  - [PATCH v2] link:
    https://lore.kernel.org/netdev/20220512093918.86084-1-lianglixue@xxxxxxxxxxxxxxxx/
Reported-by: kernel test robot <lkp@xxxxxxxxx>

 drivers/net/ethernet/intel/igb/igb_main.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c
index f8e32833226c..8ff0c698383c 100644
--- a/drivers/net/ethernet/intel/igb/igb_main.c
+++ b/drivers/net/ethernet/intel/igb/igb_main.c
@@ -241,6 +241,10 @@ static int debug = -1;
 module_param(debug, int, 0);
 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
 
+static bool allow_invalid_mac_address;
+module_param(allow_invalid_mac_address, bool, 0);
+MODULE_PARM_DESC(allow_invalid_mac_address, "Allow NIC driver to be loaded with invalid MAC address");
+
 struct igb_reg_info {
 	u32 ofs;
 	char *name;
@@ -3358,9 +3362,16 @@ static int igb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	eth_hw_addr_set(netdev, hw->mac.addr);
 
 	if (!is_valid_ether_addr(netdev->dev_addr)) {
-		dev_err(&pdev->dev, "Invalid MAC Address\n");
-		err = -EIO;
-		goto err_eeprom;
+		if (!allow_invalid_mac_address) {
+			dev_err(&pdev->dev, "Invalid MAC address\n");
+			err = -EIO;
+			goto err_eeprom;
+		} else {
+			eth_hw_addr_random(netdev);
+			ether_addr_copy(hw->mac.addr, netdev->dev_addr);
+			dev_err(&pdev->dev,
+				"Invalid MAC address. Assigned random MAC address\n");
+		}
 	}
 
 	igb_set_default_mac_filter(adapter);
-- 
2.27.0