4.14-stable review patch. If anyone has any objections, please let me know.
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From: Julian Wiedmann jwi@linux.vnet.ibm.com
[ Upstream commit b7493e91c11a757cf0f8ab26989642ee4bb2c642 ]
For z/VM NICs, qeth needs to consider which of the three CCW devices in an MPC group it uses for requesting a managed MAC address.
On the Base device, the hypervisor returns a default MAC which is pre-assigned when creating the NIC (this MAC is also returned by the READ MAC primitive). Querying any other device results in the allocation of an additional MAC address.
For consistency with READ MAC and to avoid using up more addresses than necessary, it is preferable to use the NIC's default MAC. So switch the the diag26c over to using a NIC's Read device, which should always be identical to the Base device.
Fixes: ec61bd2fd2a2 ("s390/qeth: use diag26c to get MAC address on L2") Signed-off-by: Julian Wiedmann jwi@linux.vnet.ibm.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/s390/net/qeth_core_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/s390/net/qeth_core_main.c +++ b/drivers/s390/net/qeth_core_main.c @@ -4837,7 +4837,7 @@ int qeth_vm_request_mac(struct qeth_card goto out; }
- ccw_device_get_id(CARD_DDEV(card), &id); + ccw_device_get_id(CARD_RDEV(card), &id); request->resp_buf_len = sizeof(*response); request->resp_version = DIAG26C_VERSION2; request->op_code = DIAG26C_GET_MAC;