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PCI/MSI: Handle the NOMASK flag correctly for all PCI/MSI backends

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The conversion of the XEN specific global variable pci_msi_ignore_mask to a
MSI domain flag, missed the facts that:

    1) Legacy architectures do not provide a interrupt domain
    2) Parent MSI domains do not necessarily have a domain info attached
   
Both cases result in an unconditional NULL pointer dereference. This was
unfortunatly missed in review and testing revealed it late.

Cure this by using the existing pci_msi_domain_supports() helper, which
handles all possible cases correctly.

Fixes: c3164d2e0d ("PCI/MSI: Convert pci_msi_ignore_mask to per MSI domain flag")
Reported-by: Daniel Gomez <da.gomez@kernel.org>
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Borislav Petkov <bp@alien8.de>
Tested-by: Daniel Gomez <da.gomez@kernel.org>
Link: https://lore.kernel.org/all/87iknwyp2o.ffs@tglx
Closes: https://lore.kernel.org/all/qn7fzggcj6qe6r6gdbwcz23pzdz2jx64aldccmsuheabhmjgrt@tawf5nfwuvw7
This commit is contained in:
Thomas Gleixner
2025-03-26 13:05:35 +01:00
parent dce3ab4c57
commit 3ece3e8e59
1 changed files with 6 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files
drivers/pci/msi/msi.c
+6 -12
View File
@@ -285,8 +285,6 @@ static void pci_msi_set_enable(struct pci_dev *dev, int enable)
static int msi_setup_msi_desc(struct pci_dev *dev, int nvec,
struct irq_affinity_desc *masks)
{
const struct irq_domain *d = dev_get_msi_domain(&dev->dev);
const struct msi_domain_info *info = d->host_data;
struct msi_desc desc;
u16 control;
@@ -297,7 +295,7 @@ static int msi_setup_msi_desc(struct pci_dev *dev, int nvec,
/* Lies, damned lies, and MSIs */
if (dev->dev_flags & PCI_DEV_FLAGS_HAS_MSI_MASKING)
control |= PCI_MSI_FLAGS_MASKBIT;
if (info->flags & MSI_FLAG_NO_MASK)
if (pci_msi_domain_supports(dev, MSI_FLAG_NO_MASK, DENY_LEGACY))
control &= ~PCI_MSI_FLAGS_MASKBIT;
desc.nvec_used = nvec;
@@ -604,20 +602,18 @@ static void __iomem *msix_map_region(struct pci_dev *dev,
*/
void msix_prepare_msi_desc(struct pci_dev *dev, struct msi_desc *desc)
{
const struct irq_domain *d = dev_get_msi_domain(&dev->dev);
const struct msi_domain_info *info = d->host_data;
desc->nvec_used = 1;
desc->pci.msi_attrib.is_msix = 1;
desc->pci.msi_attrib.is_64 = 1;
desc->pci.msi_attrib.default_irq = dev->irq;
desc->pci.mask_base = dev->msix_base;
desc->pci.msi_attrib.can_mask = !(info->flags & MSI_FLAG_NO_MASK) &&
!desc->pci.msi_attrib.is_virtual;
if (desc->pci.msi_attrib.can_mask) {
if (!pci_msi_domain_supports(dev, MSI_FLAG_NO_MASK, DENY_LEGACY) &&
!desc->pci.msi_attrib.is_virtual) {
void __iomem *addr = pci_msix_desc_addr(desc);
desc->pci.msi_attrib.can_mask = 1;
desc->pci.msix_ctrl = readl(addr + PCI_MSIX_ENTRY_VECTOR_CTRL);
}
}
@@ -715,8 +711,6 @@ static int msix_setup_interrupts(struct pci_dev *dev, struct msix_entry *entries
static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries,
int nvec, struct irq_affinity *affd)
{
const struct irq_domain *d = dev_get_msi_domain(&dev->dev);
const struct msi_domain_info *info = d->host_data;
int ret, tsize;
u16 control;
@@ -747,7 +741,7 @@ static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries,
/* Disable INTX */
pci_intx_for_msi(dev, 0);
if (!(info->flags & MSI_FLAG_NO_MASK)) {
if (!pci_msi_domain_supports(dev, MSI_FLAG_NO_MASK, DENY_LEGACY)) {
/*
* Ensure that all table entries are masked to prevent
* stale entries from firing in a crash kernel.