Merge tag 'stable/for-linus-fixes-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Two fixes for VCPU offlining; One to fix the string format exposed
by the xen-pci[front|back] to conform to the one used in majority of
PCI drivers; Two fixes to make the code more resilient to invalid
configurations.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

* tag 'stable/for-linus-fixes-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xenbus_dev: add missing error check to watch handling
  xen/pci[front|back]: Use %d instead of %1x for displaying PCI devfn.
  xen pvhvm: do not remap pirqs onto evtchns if !xen_have_vector_callback
  xen/smp: Fix CPU online/offline bug triggering a BUG: scheduling while atomic.
  xen/bootup: During bootup suppress XENBUS: Unable to read cpu state

7 files changed, 26 insertions, 13 deletions

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 492ade8c978e..d99346ea8fdb 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -374,7 +374,7 @@ int __init pci_xen_init(void)
 
 int __init pci_xen_hvm_init(void)
 {
-	if (!xen_feature(XENFEAT_hvm_pirqs))
+	if (!xen_have_vector_callback || !xen_feature(XENFEAT_hvm_pirqs))
 		return 0;
 
 #ifdef CONFIG_ACPI
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 041d4fe9dfe4..501d4e0244ba 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -409,6 +409,13 @@ static void __cpuinit xen_play_dead(void) /* used only with HOTPLUG_CPU */
 	play_dead_common();
 	HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL);
 	cpu_bringup();
+	/*
+	 * Balance out the preempt calls - as we are running in cpu_idle
+	 * loop which has been called at bootup from cpu_bringup_and_idle.
+	 * The cpucpu_bringup_and_idle called cpu_bringup which made a
+	 * preempt_disable() So this preempt_enable will balance it out.
+	 */
+	preempt_enable();
 }
 
 #else /* !CONFIG_HOTPLUG_CPU */
diff --git a/drivers/pci/xen-pcifront.c b/drivers/pci/xen-pcifront.c
index 7cf3d2fcf56a..1620088a0e7e 100644
--- a/drivers/pci/xen-pcifront.c
+++ b/drivers/pci/xen-pcifront.c
@@ -189,7 +189,7 @@ static int pcifront_bus_read(struct pci_bus *bus, unsigned int devfn,
 
 	if (verbose_request)
 		dev_info(&pdev->xdev->dev,
-			 "read dev=%04x:%02x:%02x.%01x - offset %x size %d\n",
+			 "read dev=%04x:%02x:%02x.%d - offset %x size %d\n",
 			 pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
 			 PCI_FUNC(devfn), where, size);
 
@@ -228,7 +228,7 @@ static int pcifront_bus_write(struct pci_bus *bus, unsigned int devfn,
 
 	if (verbose_request)
 		dev_info(&pdev->xdev->dev,
-			 "write dev=%04x:%02x:%02x.%01x - "
+			 "write dev=%04x:%02x:%02x.%d - "
 			 "offset %x size %d val %x\n",
 			 pci_domain_nr(bus), bus->number,
 			 PCI_SLOT(devfn), PCI_FUNC(devfn), where, size, val);
@@ -432,7 +432,7 @@ static int __devinit pcifront_scan_bus(struct pcifront_device *pdev,
 		d = pci_scan_single_device(b, devfn);
 		if (d)
 			dev_info(&pdev->xdev->dev, "New device on "
-				 "%04x:%02x:%02x.%02x found.\n", domain, bus,
+				 "%04x:%02x:%02x.%d found.\n", domain, bus,
 				 PCI_SLOT(devfn), PCI_FUNC(devfn));
 	}
 
@@ -1041,7 +1041,7 @@ static int pcifront_detach_devices(struct pcifront_device *pdev)
 		pci_dev = pci_get_slot(pci_bus, PCI_DEVFN(slot, func));
 		if (!pci_dev) {
 			dev_dbg(&pdev->xdev->dev,
-				"Cannot get PCI device %04x:%02x:%02x.%02x\n",
+				"Cannot get PCI device %04x:%02x:%02x.%d\n",
 				domain, bus, slot, func);
 			continue;
 		}
@@ -1049,7 +1049,7 @@ static int pcifront_detach_devices(struct pcifront_device *pdev)
 		pci_dev_put(pci_dev);
 
 		dev_dbg(&pdev->xdev->dev,
-			"PCI device %04x:%02x:%02x.%02x removed.\n",
+			"PCI device %04x:%02x:%02x.%d removed.\n",
 			domain, bus, slot, func);
 	}
 
diff --git a/drivers/xen/cpu_hotplug.c b/drivers/xen/cpu_hotplug.c
index 14e2d995e958..4dcfced107f5 100644
--- a/drivers/xen/cpu_hotplug.c
+++ b/drivers/xen/cpu_hotplug.c
@@ -30,7 +30,8 @@ static int vcpu_online(unsigned int cpu)
 	sprintf(dir, "cpu/%u", cpu);
 	err = xenbus_scanf(XBT_NIL, dir, "availability", "%s", state);
 	if (err != 1) {
-		printk(KERN_ERR "XENBUS: Unable to read cpu state\n");
+		if (!xen_initial_domain())
+			printk(KERN_ERR "XENBUS: Unable to read cpu state\n");
 		return err;
 	}
 
diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
index 7944a17f5cbf..19834d1c7c36 100644
--- a/drivers/xen/xen-pciback/pci_stub.c
+++ b/drivers/xen/xen-pciback/pci_stub.c
@@ -884,7 +884,7 @@ static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
 	int err;
 
 	err =
-	    sscanf(buf, " %04x:%02x:%02x.%1x-%08x:%1x:%08x", domain, bus, slot,
+	    sscanf(buf, " %04x:%02x:%02x.%d-%08x:%1x:%08x", domain, bus, slot,
 		   func, reg, size, mask);
 	if (err == 7)
 		return 0;
@@ -904,7 +904,7 @@ static int pcistub_device_id_add(int domain, int bus, int slot, int func)
 	pci_dev_id->bus = bus;
 	pci_dev_id->devfn = PCI_DEVFN(slot, func);
 
-	pr_debug(DRV_NAME ": wants to seize %04x:%02x:%02x.%01x\n",
+	pr_debug(DRV_NAME ": wants to seize %04x:%02x:%02x.%d\n",
 		 domain, bus, slot, func);
 
 	spin_lock_irqsave(&device_ids_lock, flags);
@@ -934,7 +934,7 @@ static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
 
 			err = 0;
 
-			pr_debug(DRV_NAME ": removed %04x:%02x:%02x.%01x from "
+			pr_debug(DRV_NAME ": removed %04x:%02x:%02x.%d from "
 				 "seize list\n", domain, bus, slot, func);
 		}
 	}
@@ -1029,7 +1029,7 @@ static ssize_t pcistub_slot_show(struct device_driver *drv, char *buf)
 			break;
 
 		count += scnprintf(buf + count, PAGE_SIZE - count,
-				   "%04x:%02x:%02x.%01x\n",
+				   "%04x:%02x:%02x.%d\n",
 				   pci_dev_id->domain, pci_dev_id->bus,
 				   PCI_SLOT(pci_dev_id->devfn),
 				   PCI_FUNC(pci_dev_id->devfn));
diff --git a/drivers/xen/xen-pciback/xenbus.c b/drivers/xen/xen-pciback/xenbus.c
index d5dcf8d5d3d9..64b11f99eacc 100644
--- a/drivers/xen/xen-pciback/xenbus.c
+++ b/drivers/xen/xen-pciback/xenbus.c
@@ -206,6 +206,7 @@ static int xen_pcibk_publish_pci_dev(struct xen_pcibk_device *pdev,
 		goto out;
 	}
 
+	/* Note: The PV protocol uses %02x, don't change it */
 	err = xenbus_printf(XBT_NIL, pdev->xdev->nodename, str,
 			    "%04x:%02x:%02x.%02x", domain, bus,
 			    PCI_SLOT(devfn), PCI_FUNC(devfn));
@@ -229,7 +230,7 @@ static int xen_pcibk_export_device(struct xen_pcibk_device *pdev,
 		err = -EINVAL;
 		xenbus_dev_fatal(pdev->xdev, err,
 				 "Couldn't locate PCI device "
-				 "(%04x:%02x:%02x.%01x)! "
+				 "(%04x:%02x:%02x.%d)! "
 				 "perhaps already in-use?",
 				 domain, bus, slot, func);
 		goto out;
@@ -274,7 +275,7 @@ static int xen_pcibk_remove_device(struct xen_pcibk_device *pdev,
 	if (!dev) {
 		err = -EINVAL;
 		dev_dbg(&pdev->xdev->dev, "Couldn't locate PCI device "
-			"(%04x:%02x:%02x.%01x)! not owned by this domain\n",
+			"(%04x:%02x:%02x.%d)! not owned by this domain\n",
 			domain, bus, slot, func);
 		goto out;
 	}
diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c
index 527dc2a3b89f..89f76252a16f 100644
--- a/drivers/xen/xenbus/xenbus_dev_frontend.c
+++ b/drivers/xen/xenbus/xenbus_dev_frontend.c
@@ -369,6 +369,10 @@ static int xenbus_write_watch(unsigned msg_type, struct xenbus_file_priv *u)
 		goto out;
 	}
 	token++;
+	if (memchr(token, 0, u->u.msg.len - (token - path)) == NULL) {
+		rc = -EILSEQ;
+		goto out;
+	}
 
 	if (msg_type == XS_WATCH) {
 		watch = alloc_watch_adapter(path, token);