Commit 85aa607e authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

PCI/MSI: Sanitize MSI-X table map handling 



Unmapping the MSI-X base mapping in the loops which allocate/free MSI
descriptors is daft and in the way of allowing runtime expansion of MSI-X
descriptors.

Store the mapping in struct pci_dev and free it after freeing the MSI-X
descriptors.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Tested-by: default avatarJuergen Gross <jgross@suse.com>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Acked-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20211206210224.871651518@linutronix.de
parent aa423ac4

drivers/pci/msi/msi.c

+8 −10
Original line number Diff line number Diff line
@@ -241,14 +241,14 @@ static void free_msi_irqs(struct pci_dev *dev) 
	pci_msi_teardown_msi_irqs(dev);



	list_for_each_entry_safe(entry, tmp, msi_list, list) {

		if (entry->pci.msi_attrib.is_msix) {

			if (list_is_last(&entry->list, msi_list))

				iounmap(entry->pci.mask_base);

		}



		list_del(&entry->list);

		free_msi_entry(entry);

	}



	if (dev->msix_base) {

		iounmap(dev->msix_base);

		dev->msix_base = NULL;

	}

}



static void pci_intx_for_msi(struct pci_dev *dev, int enable)
@@ -501,10 +501,6 @@ static int msix_setup_entries(struct pci_dev *dev, void __iomem *base, 
	for (i = 0, curmsk = masks; i < nvec; i++) {

		entry = alloc_msi_entry(&dev->dev, 1, curmsk);

		if (!entry) {

			if (!i)

				iounmap(base);

			else

				free_msi_irqs(dev);

			/* No enough memory. Don't try again */

			ret = -ENOMEM;

			goto out;
@@ -602,12 +598,14 @@ static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries, 
		goto out_disable;

	}



	dev->msix_base = base;



	/* Ensure that all table entries are masked. */

	msix_mask_all(base, tsize);



	ret = msix_setup_entries(dev, base, entries, nvec, affd);

	if (ret)

		goto out_disable;

		goto out_free;



	ret = pci_msi_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);

	if (ret)

include/linux/pci.h

+1 −0
Original line number Diff line number Diff line
@@ -473,6 +473,7 @@ struct pci_dev { 
	u8		ptm_granularity;

#endif

#ifdef CONFIG_PCI_MSI

	void __iomem	*msix_base;

	const struct attribute_group **msi_irq_groups;

#endif

	struct pci_vpd	vpd;