Re: [PATCH 12/42] PCI: aardvark: Check for virq mapping when processing INTx IRQ
From: Marc Zyngier <maz@kernel.org>
Date: 2021-06-04 16:29:42
Also in:
linux-arm-kernel, linux-pci
On Fri, 04 Jun 2021 17:24:51 +0100, Pali Rohár [off-list ref] wrote:
On Friday 07 May 2021 10:15:39 Marc Zyngier wrote:quoted
On Thu, 06 May 2021 16:31:23 +0100, Pali Rohár [off-list ref] wrote:quoted
It is possible that we receive spurious INTx interrupt. So add needed check before calling generic_handle_irq() function. Signed-off-by: Pali Rohár <pali@kernel.org> Reviewed-by: Marek Behún <kabel@kernel.org> Cc: stable@vger.kernel.org --- drivers/pci/controller/pci-aardvark.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c index 362faddae935..e7089db11f79 100644 --- a/drivers/pci/controller/pci-aardvark.c +++ b/drivers/pci/controller/pci-aardvark.c@@ -1106,7 +1106,10 @@ static void advk_pcie_handle_int(struct advk_pcie *pcie) PCIE_ISR1_REG); virq = irq_find_mapping(pcie->irq_domain, i); - generic_handle_irq(virq); + if (virq) + generic_handle_irq(virq); + else + dev_err(&pcie->pdev->dev, "unexpected INT%c IRQ\n", (char)i+'A');Please don't scream like this. This is the best way to get into a DoS situation if you interrupt rate is high enough. At least rate-limit it.Ok, I will fix it! Just to note that this code pattern is used also in other drivers. So other drivers should fixed too...
"We should fix the kernel" is a common theme. Please go ahead. M. -- Without deviation from the norm, progress is not possible.