From e791380340685698dbdd38c7e3f3fcbf70a3c832 Mon Sep 17 00:00:00 2001 From: John Allen Date: Thu, 18 Jan 2018 16:27:12 -0600 Subject: [PATCH] ibmvnic: Revert to previous mtu when unsupported value requested If we request an unsupported mtu value, the vnic server will suggest a different value. Currently we take the suggested value without question and login with that value. However, the behavior doesn't seem completely sane as attempting to change the mtu to some specific value will change the mtu to some completely different value most of the time. This patch fixes the issue by logging in with the previously used mtu value and printing an error message saying that the given mtu is unsupported. Signed-off-by: John Allen Reviewed-by: Nathan Fontenot Signed-off-by: David S. Miller --- drivers/net/ethernet/ibm/ibmvnic.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index 7f75d01432ef..cc36b254917c 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -3623,7 +3623,17 @@ static void handle_request_cap_rsp(union ibmvnic_crq *crq, *req_value, (long int)be64_to_cpu(crq->request_capability_rsp. number), name); - *req_value = be64_to_cpu(crq->request_capability_rsp.number); + + if (be16_to_cpu(crq->request_capability_rsp.capability) == + REQ_MTU) { + pr_err("mtu of %llu is not supported. Reverting.\n", + *req_value); + *req_value = adapter->fallback.mtu; + } else { + *req_value = + be64_to_cpu(crq->request_capability_rsp.number); + } + ibmvnic_send_req_caps(adapter, 1); return; default: -- 2.30.2