From: Thomas Gleixner <tglx@linutronix.de>
Date: Fri, 11 Nov 2022 13:54:15 +0000 (+0100)
Subject: PCI/MSI: Check for MSI enabled in __pci_msix_enable()
X-Git-Tag: v6.2-rc1~195^2~104
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=fe97f59a78fefda6c4a8c8ee6a070b1f769fc801;p=thirdparty%2Fkernel%2Flinux.git

PCI/MSI: Check for MSI enabled in __pci_msix_enable()

PCI/MSI and PCI/MSI-X are mutually exclusive, but the MSI-X enable code
lacks a check for already enabled MSI.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ashok Raj <ashok.raj@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20221111122013.653556720@linutronix.de
---

diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
index fdd2ec09651e9..160af9f016698 100644
--- a/drivers/pci/msi/msi.c
+++ b/drivers/pci/msi/msi.c
@@ -935,6 +935,11 @@ static int __pci_enable_msix_range(struct pci_dev *dev,
 	if (maxvec < minvec)
 		return -ERANGE;
 
+	if (dev->msi_enabled) {
+		pci_info(dev, "can't enable MSI-X (MSI already enabled)\n");
+		return -EINVAL;
+	}
+
 	if (WARN_ON_ONCE(dev->msix_enabled))
 		return -EINVAL;