diff mbox series

[net-next] ibmvnic: Harden device Command Response Queue handshake

Message ID 1598893197-14450-1-git-send-email-tlfalcon@linux.ibm.com
State New
Headers show
Series [net-next] ibmvnic: Harden device Command Response Queue handshake | expand

Commit Message

Thomas Falcon Aug. 31, 2020, 4:59 p.m. UTC
In some cases, the device or firmware may be busy when the
driver attempts to perform the CRQ initialization handshake.
If the partner is busy, the hypervisor will return the H_CLOSED
return code. The aim of this patch is that, if the device is not
ready, to query the device a number of times, with a small wait
time in between queries. If all initialization requests fail,
the driver will remain in a dormant state, awaiting a signal
from the device that it is ready for operation.

Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>
---
 drivers/net/ethernet/ibm/ibmvnic.c | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

Comments

David Miller Sept. 1, 2020, 8:15 p.m. UTC | #1
From: Thomas Falcon <tlfalcon@linux.ibm.com>
Date: Mon, 31 Aug 2020 11:59:57 -0500

> In some cases, the device or firmware may be busy when the
> driver attempts to perform the CRQ initialization handshake.
> If the partner is busy, the hypervisor will return the H_CLOSED
> return code. The aim of this patch is that, if the device is not
> ready, to query the device a number of times, with a small wait
> time in between queries. If all initialization requests fail,
> the driver will remain in a dormant state, awaiting a signal
> from the device that it is ready for operation.
> 
> Signed-off-by: Thomas Falcon <tlfalcon@linux.ibm.com>

Applied to net-next, thank you.
diff mbox series

Patch

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 86a83e5..9943586 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -3566,14 +3566,31 @@  static int ibmvnic_send_crq(struct ibmvnic_adapter *adapter,
 
 static int ibmvnic_send_crq_init(struct ibmvnic_adapter *adapter)
 {
+	struct device *dev = &adapter->vdev->dev;
 	union ibmvnic_crq crq;
+	int retries = 100;
+	int rc;
 
 	memset(&crq, 0, sizeof(crq));
 	crq.generic.first = IBMVNIC_CRQ_INIT_CMD;
 	crq.generic.cmd = IBMVNIC_CRQ_INIT;
 	netdev_dbg(adapter->netdev, "Sending CRQ init\n");
 
-	return ibmvnic_send_crq(adapter, &crq);
+	do {
+		rc = ibmvnic_send_crq(adapter, &crq);
+		if (rc != H_CLOSED)
+			break;
+		retries--;
+		msleep(50);
+
+	} while (retries > 0);
+
+	if (rc) {
+		dev_err(dev, "Failed to send init request, rc = %d\n", rc);
+		return rc;
+	}
+
+	return 0;
 }
 
 static int send_version_xchg(struct ibmvnic_adapter *adapter)