850-0005-PCI-aardvark-Check-return-value-of-generic_handle_do.patch

From 69c1f2c6f45a556361fd8e8d2d4eb20e2c8d3d95 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
Date: Thu, 18 Mar 2021 17:04:32 +0100
Subject: [PATCH] PCI: aardvark: Check return value of
 generic_handle_domain_irq() when processing INTx IRQ
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It is possible that we receive spurious INTx interrupt. Check for the
return value of generic_handle_domain_irq() when processing INTx IRQ.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <kabel@kernel.org>
---
 drivers/pci/controller/pci-aardvark.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/pci/controller/pci-aardvark.c
+++ b/drivers/pci/controller/pci-aardvark.c
@@ -1431,7 +1431,9 @@ static void advk_pcie_handle_int(struct
 		advk_writel(pcie, PCIE_ISR1_INTX_ASSERT(i),
 			    PCIE_ISR1_REG);
 
-		generic_handle_domain_irq(pcie->irq_domain, i);
+		if (generic_handle_domain_irq(pcie->irq_domain, i) == -EINVAL)
+			dev_err_ratelimited(&pcie->pdev->dev, "unexpected INT%c IRQ\n",
+					    (char)i + 'A');
 	}
 }