[PATCH net] ibmvnic: Only do H_EOI for mobility events

[PATCH net] ibmvnic: Only do H_EOI for mobility events

[Nathan Fontenot]

When enabling the sub-CRQ IRQ a previous update sent a H_EOI prior
to the enablement to clear any pending interrupts that may be present
across a partition migration. This fixed a firmware bug where a
migration could erroneously indicate that a H_EOI was pending.

The H_EOI should only be sent when enabling during a mobility
event though. Doing so at other time could wrong and can produce
extra driver output when IRQs are enabled when doing TX completion.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
---
 drivers/net/ethernet/ibm/ibmvnic.c |   15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 4bb4646a5f92..62cd3602c633 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -2617,18 +2617,21 @@ static int enable_scrq_irq(struct ibmvnic_adapter *adapter,
 {
 	struct device *dev = &adapter->vdev->dev;
 	unsigned long rc;
-	u64 val;
 
 	if (scrq->hw_irq > 0x100000000ULL) {
 		dev_err(dev, "bad hw_irq = %lx\n", scrq->hw_irq);
 		return 1;
 	}
 
-	val = (0xff000000) | scrq->hw_irq;
-	rc = plpar_hcall_norets(H_EOI, val);
-	if (rc)
-		dev_err(dev, "H_EOI FAILED irq 0x%llx. rc=%ld\n",
-			val, rc);
+	if (adapter->resetting &&
+	    adapter->reset_reason == VNIC_RESET_MOBILITY) {
+		u64 val = (0xff000000) | scrq->hw_irq;
+
+		rc = plpar_hcall_norets(H_EOI, val);
+		if (rc)
+			dev_err(dev, "H_EOI FAILED irq 0x%llx. rc=%ld\n",
+				val, rc);
+	}
 
 	rc = plpar_hcall_norets(H_VIOCTL, adapter->vdev->unit_address,
 				H_ENABLE_VIO_INTERRUPT, scrq->hw_irq, 0, 0);

Re: [PATCH net] ibmvnic: Only do H_EOI for mobility events

[David Miller]

From: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Date: Tue, 22 May 2018 11:21:10 -0500

> When enabling the sub-CRQ IRQ a previous update sent a H_EOI prior
> to the enablement to clear any pending interrupts that may be present
> across a partition migration. This fixed a firmware bug where a
> migration could erroneously indicate that a H_EOI was pending.
> 
> The H_EOI should only be sent when enabling during a mobility
> event though. Doing so at other time could wrong and can produce
> extra driver output when IRQs are enabled when doing TX completion.
> 
> Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>

Applied, thanks.