Subject: [PATCH] net: thunderx: Do not invoke pci_irq_vector() from interrupt context

From: Thomas Gleixner <[email-masked]>
Date: Fri, 29 Apr 2022 15:54:24 +0200

pci_irq_vector() can't be used in atomic context any longer. This conflicts
with the usage of this function in nic_mbx_intr_handler().

Cache the Linux interrupt numbers in struct nicpf and use that cache in the
interrupt handler to select the mailbox.

Fixes: 495c66aca3da ("genirq/msi: Convert to new functions")
Reported-by: Ondrej Mosnacek <[email-masked]>
Signed-off-by: Thomas Gleixner <[email-masked]>
Cc: Sunil Goutham <[email-masked]>
Cc: "David S. Miller" <[email-masked]>
Cc: Jakub Kicinski <[email-masked]>
Cc: Paolo Abeni <[email-masked]>
Cc: [email-masked]
Cc: [email-masked]
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2041772
---
 drivers/net/ethernet/cavium/thunder/nic_main.c |   16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

--- a/drivers/net/ethernet/cavium/thunder/nic_main.c
+++ b/drivers/net/ethernet/cavium/thunder/nic_main.c
@@ -59,7 +59,7 @@ struct nicpf {
 
 	/* MSI-X */
 	u8			num_vec;
-	bool			irq_allocated[NIC_PF_MSIX_VECTORS];
+	unsigned int		irq_allocated[NIC_PF_MSIX_VECTORS];
 	char			irq_name[NIC_PF_MSIX_VECTORS][20];
 };
 
@@ -1150,7 +1150,7 @@ static irqreturn_t nic_mbx_intr_handler(
 	u64 intr;
 	u8  vf;
 
-	if (irq == pci_irq_vector(nic->pdev, NIC_PF_INTR_ID_MBOX0))
+	if (irq == nic->irq_allocated[NIC_PF_INTR_ID_MBOX0])
 		mbx = 0;
 	else
 		mbx = 1;
@@ -1176,14 +1176,14 @@ static void nic_free_all_interrupts(stru
 
 	for (irq = 0; irq < nic->num_vec; irq++) {
 		if (nic->irq_allocated[irq])
-			free_irq(pci_irq_vector(nic->pdev, irq), nic);
-		nic->irq_allocated[irq] = false;
+			free_irq(nic->irq_allocated[irq], nic);
+		nic->irq_allocated[irq] = 0;
 	}
 }
 
 static int nic_register_interrupts(struct nicpf *nic)
 {
-	int i, ret;
+	int i, ret, irq;
 	nic->num_vec = pci_msix_vec_count(nic->pdev);
 
 	/* Enable MSI-X */
@@ -1201,13 +1201,13 @@ static int nic_register_interrupts(struc
 		sprintf(nic->irq_name[i],
 			"NICPF Mbox%d", (i - NIC_PF_INTR_ID_MBOX0));
 
-		ret = request_irq(pci_irq_vector(nic->pdev, i),
-				  nic_mbx_intr_handler, 0,
+		irq = pci_irq_vector(nic->pdev, i);
+		ret = request_irq(irq, nic_mbx_intr_handler, 0,
 				  nic->irq_name[i], nic);
 		if (ret)
 			goto fail;
 
-		nic->irq_allocated[i] = true;
+		nic->irq_allocated[i] = irq;
 	}
 
 	/* Enable mailbox interrupt */