3 files changed, 9 insertions, 1 deletions

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 093f5f4272d3..5ef62ed20ba4 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -427,6 +427,7 @@ int __init pci_xen_init(void)
         x86_msi.teardown_msi_irqs = xen_teardown_msi_irqs;
         x86_msi.msi_mask_irq = xen_nop_msi_mask_irq;
         x86_msi.msix_mask_irq = xen_nop_msix_mask_irq;
+        pci_msi_ignore_mask = 1;
 #endif
         return 0;
 }
@@ -508,6 +509,7 @@ int __init pci_xen_initial_domain(void)
         x86_msi.restore_msi_irqs = xen_initdom_restore_msi_irqs;
         x86_msi.msi_mask_irq = xen_nop_msi_mask_irq;
         x86_msi.msix_mask_irq = xen_nop_msix_mask_irq;
+        pci_msi_ignore_mask = 1;
 #endif
         xen_setup_acpi_sci();
         __acpi_register_gsi = acpi_register_gsi_xen;
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 9fab30af0e75..066c2fb9763a 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -23,6 +23,7 @@
 #include "pci.h"
 
 static int pci_msi_enable = 1;
+int pci_msi_ignore_mask;
 
 #define msix_table_size(flags)  ((flags & PCI_MSIX_FLAGS_QSIZE) + 1)
 
@@ -167,7 +168,7 @@ u32 default_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
 {
         u32 mask_bits = desc->masked;
 
-        if (!desc->msi_attrib.maskbit)
+        if (pci_msi_ignore_mask || !desc->msi_attrib.maskbit)
                 return 0;
 
         mask_bits &= ~mask;
@@ -199,6 +200,10 @@ u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag)
         u32 mask_bits = desc->masked;
         unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
                                                 PCI_MSIX_ENTRY_VECTOR_CTRL;
+
+        if (pci_msi_ignore_mask)
+                return 0;
+
         mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT;
         if (flag)
                 mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
diff --git a/include/linux/msi.h b/include/linux/msi.h
index 44f4746d033b..86dc501a1534 100644
--- a/include/linux/msi.h
+++ b/include/linux/msi.h
@@ -10,6 +10,7 @@ struct msi_msg {
         u32     data;           /* 16 bits of msi message data */
 };
 
+extern int pci_msi_ignore_mask;
 /* Helper functions */
 struct irq_data;
 struct msi_desc;