[tip: irq/core] PCI/MSI: Reject MSI-X early

[tip-bot2 for Thomas Gleixner]

The following commit has been merged into the irq/core branch of tip:

Commit-ID:     99f3d279765725920aa5924fa445537a20129a6f
Gitweb:        https://git.kernel.org/tip/99f3d279765725920aa5924fa445537a20129a6f
Author:        Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate:    Fri, 11 Nov 2022 14:55:11 +01:00
Committer:     Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Thu, 17 Nov 2022 15:15:22 +01:00

PCI/MSI: Reject MSI-X early

Similar to PCI multi-MSI reject MSI-X enablement when a irq domain is
attached to the device which does not support MSI-X.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221111122015.631728309@xxxxxxxxxxxxx

---
 drivers/pci/msi/msi.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c
index bc84647..0740acd 100644
--- a/drivers/pci/msi/msi.c
+++ b/drivers/pci/msi/msi.c
@@ -762,6 +762,10 @@ int __pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries, int
 	if (WARN_ON_ONCE(dev->msix_enabled))
 		return -EINVAL;
 
+	/* Check MSI-X early on irq domain enabled architectures */
+	if (!pci_msi_domain_supports(dev, MSI_FLAG_PCI_MSIX, ALLOW_LEGACY))
+		return -ENOTSUPP;
+
 	if (!pci_msi_supported(dev, nvec) || dev->current_state != PCI_D0)
 		return -EINVAL;