Merge tag 'stable/for-linus-3.18-b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen bug fixes from David Vrabel:

 - Fix regression in xen_clocksource_read() which caused all Xen guests
   to crash early in boot.
 - Several fixes for super rare race conditions in the p2m.
 - Assorted other minor fixes.

* tag 'stable/for-linus-3.18-b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/pci: Allocate memory for physdev_pci_device_add's optarr
  x86/xen: panic on bad Xen-provided memory map
  x86/xen: Fix incorrect per_cpu accessor in xen_clocksource_read()
  x86/xen: avoid race in p2m handling
  x86/xen: delay construction of mfn_list_list
  x86/xen: avoid writing to freed memory after race in p2m handling
  xen/balloon: Don't continue ballooning when BP_ECANCELED is encountered

2 files changed, 19 insertions, 11 deletions

diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 1e0a317d3dcd..3860d02729dc 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -167,6 +167,9 @@ static struct page *balloon_next_page(struct page *page)
 
 static enum bp_state update_schedule(enum bp_state state)
 {
+	if (state == BP_ECANCELED)
+		return BP_ECANCELED;
+
 	if (state == BP_DONE) {
 		balloon_stats.schedule_delay = 1;
 		balloon_stats.retry_count = 1;
diff --git a/drivers/xen/pci.c b/drivers/xen/pci.c
index dd9c249ea311..95ee4302ffb8 100644
--- a/drivers/xen/pci.c
+++ b/drivers/xen/pci.c
@@ -41,24 +41,29 @@ static int xen_add_device(struct device *dev)
 #endif
 
 	if (pci_seg_supported) {
-		struct physdev_pci_device_add add = {
-			.seg = pci_domain_nr(pci_dev->bus),
-			.bus = pci_dev->bus->number,
-			.devfn = pci_dev->devfn
+		struct {
+			struct physdev_pci_device_add add;
+			uint32_t pxm;
+		} add_ext = {
+			.add.seg = pci_domain_nr(pci_dev->bus),
+			.add.bus = pci_dev->bus->number,
+			.add.devfn = pci_dev->devfn
 		};
+		struct physdev_pci_device_add *add = &add_ext.add;
+
 #ifdef CONFIG_ACPI
 		acpi_handle handle;
 #endif
 
 #ifdef CONFIG_PCI_IOV
 		if (pci_dev->is_virtfn) {
-			add.flags = XEN_PCI_DEV_VIRTFN;
-			add.physfn.bus = physfn->bus->number;
-			add.physfn.devfn = physfn->devfn;
+			add->flags = XEN_PCI_DEV_VIRTFN;
+			add->physfn.bus = physfn->bus->number;
+			add->physfn.devfn = physfn->devfn;
 		} else
 #endif
 		if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn))
-			add.flags = XEN_PCI_DEV_EXTFN;
+			add->flags = XEN_PCI_DEV_EXTFN;
 
 #ifdef CONFIG_ACPI
 		handle = ACPI_HANDLE(&pci_dev->dev);
@@ -77,8 +82,8 @@ static int xen_add_device(struct device *dev)
 				status = acpi_evaluate_integer(handle, "_PXM",
 							       NULL, &pxm);
 				if (ACPI_SUCCESS(status)) {
-					add.optarr[0] = pxm;
-					add.flags |= XEN_PCI_DEV_PXM;
+					add->optarr[0] = pxm;
+					add->flags |= XEN_PCI_DEV_PXM;
 					break;
 				}
 				status = acpi_get_parent(handle, &handle);
@@ -86,7 +91,7 @@ static int xen_add_device(struct device *dev)
 		}
 #endif /* CONFIG_ACPI */
 
-		r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_add, &add);
+		r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_add, add);
 		if (r != -ENOSYS)
 			return r;
 		pci_seg_supported = false;