Fixes in various components:

* mechanism to work with misconfigured backends (where they are
    advertised but in reality don't exist).
  * two tiny compile warning fixes.
  * proper error handling in gnttab_resume
  * Not using VM_PFNMAP anymore to allow backends in the same domain.
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Merge tag 'stable/for-linus-3.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull xen fixes from Konrad Rzeszutek Wilk:
 - mechanism to work with misconfigured backends (where they are
   advertised but in reality don't exist).
 - two tiny compile warning fixes.
 - proper error handling in gnttab_resume
 - Not using VM_PFNMAP anymore to allow backends in the same domain.

* tag 'stable/for-linus-3.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  Revert "xen/p2m: m2p_find_override: use list_for_each_entry_safe"
  xen/resume: Fix compile warnings.
  xen/xenbus: Add quirk to deal with misconfigured backends.
  xen/blkback: Fix warning error.
  xen/p2m: m2p_find_override: use list_for_each_entry_safe
  xen/gntdev: do not set VM_PFNMAP
  xen/grant-table: add error-handling code on failure of gnttab_resume

drivers/block/xen-blkback/xenbus.c

@@ -416,7 +416,7 @@ static void xen_blkbk_discard(struct xenbus_transaction xbt, struct backend_info
 				    "discard-secure", "%d",
 				    blkif->vbd.discard_secure);
 		if (err) {
-			dev_warn(dev-dev, "writing discard-secure (%d)", err);
+			dev_warn(&dev->dev, "writing discard-secure (%d)", err);
 			return;
 		}
 	}

drivers/xen/gntdev.c

@@ -722,7 +722,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
 	vma->vm_flags |= VM_RESERVED|VM_DONTEXPAND;
 
 	if (use_ptemod)
-		vma->vm_flags |= VM_DONTCOPY|VM_PFNMAP;
+		vma->vm_flags |= VM_DONTCOPY;
 
 	vma->vm_private_data = map;
 

drivers/xen/grant-table.c

@@ -1029,6 +1029,7 @@ int gnttab_init(void)
 	int i;
 	unsigned int max_nr_glist_frames, nr_glist_frames;
 	unsigned int nr_init_grefs;
+	int ret;
 
 	nr_grant_frames = 1;
 	boot_max_nr_grant_frames = __max_nr_grant_frames();
@@ -1047,12 +1048,16 @@ int gnttab_init(void)
 	nr_glist_frames = (nr_grant_frames * GREFS_PER_GRANT_FRAME + RPP - 1) / RPP;
 	for (i = 0; i < nr_glist_frames; i++) {
 		gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_KERNEL);
-		if (gnttab_list[i] == NULL)
+		if (gnttab_list[i] == NULL) {
+			ret = -ENOMEM;
 			goto ini_nomem;
+		}
 	}
 
-	if (gnttab_resume() < 0)
-		return -ENODEV;
+	if (gnttab_resume() < 0) {
+		ret = -ENODEV;
+		goto ini_nomem;
+	}
 
 	nr_init_grefs = nr_grant_frames * GREFS_PER_GRANT_FRAME;
 
@@ -1070,7 +1075,7 @@ int gnttab_init(void)
 	for (i--; i >= 0; i--)
 		free_page((unsigned long)gnttab_list[i]);
 	kfree(gnttab_list);
-	return -ENOMEM;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(gnttab_init);
 

drivers/xen/manage.c

@@ -132,6 +132,7 @@ static void do_suspend(void)
 	err = dpm_suspend_end(PMSG_FREEZE);
 	if (err) {
 		printk(KERN_ERR "dpm_suspend_end failed: %d\n", err);
+		si.cancelled = 0;
 		goto out_resume;
 	}
 

drivers/xen/xenbus/xenbus_probe_frontend.c

@@ -135,7 +135,7 @@ static int read_backend_details(struct xenbus_device *xendev)
 	return xenbus_read_otherend_details(xendev, "backend-id", "backend");
 }
 
-static int is_device_connecting(struct device *dev, void *data)
+static int is_device_connecting(struct device *dev, void *data, bool ignore_nonessential)
 {
 	struct xenbus_device *xendev = to_xenbus_device(dev);
 	struct device_driver *drv = data;
@@ -152,16 +152,41 @@ static int is_device_connecting(struct device *dev, void *data)
 	if (drv && (dev->driver != drv))
 		return 0;
 
+	if (ignore_nonessential) {
+		/* With older QEMU, for PVonHVM guests the guest config files
+		 * could contain: vfb = [ 'vnc=1, vnclisten=0.0.0.0']
+		 * which is nonsensical as there is no PV FB (there can be
+		 * a PVKB) running as HVM guest. */
+
+		if ((strncmp(xendev->nodename, "device/vkbd", 11) == 0))
+			return 0;
+
+		if ((strncmp(xendev->nodename, "device/vfb", 10) == 0))
+			return 0;
+	}
 	xendrv = to_xenbus_driver(dev->driver);
 	return (xendev->state < XenbusStateConnected ||
 		(xendev->state == XenbusStateConnected &&
 		 xendrv->is_ready && !xendrv->is_ready(xendev)));
 }
+static int essential_device_connecting(struct device *dev, void *data)
+{
+	return is_device_connecting(dev, data, true /* ignore PV[KBB+FB] */);
+}
+static int non_essential_device_connecting(struct device *dev, void *data)
+{
+	return is_device_connecting(dev, data, false);
+}
 
-static int exists_connecting_device(struct device_driver *drv)
+static int exists_essential_connecting_device(struct device_driver *drv)
 {
 	return bus_for_each_dev(&xenbus_frontend.bus, NULL, drv,
-				is_device_connecting);
+				essential_device_connecting);
+}
+static int exists_non_essential_connecting_device(struct device_driver *drv)
+{
+	return bus_for_each_dev(&xenbus_frontend.bus, NULL, drv,
+				non_essential_device_connecting);
 }
 
 static int print_device_status(struct device *dev, void *data)
@@ -192,6 +217,23 @@ static int print_device_status(struct device *dev, void *data)
 /* We only wait for device setup after most initcalls have run. */
 static int ready_to_wait_for_devices;
 
+static bool wait_loop(unsigned long start, unsigned int max_delay,
+		     unsigned int *seconds_waited)
+{
+	if (time_after(jiffies, start + (*seconds_waited+5)*HZ)) {
+		if (!*seconds_waited)
+			printk(KERN_WARNING "XENBUS: Waiting for "
+			       "devices to initialise: ");
+		*seconds_waited += 5;
+		printk("%us...", max_delay - *seconds_waited);
+		if (*seconds_waited == max_delay)
+			return true;
+	}
+
+	schedule_timeout_interruptible(HZ/10);
+
+	return false;
+}
 /*
  * On a 5-minute timeout, wait for all devices currently configured.  We need
  * to do this to guarantee that the filesystems and / or network devices
@@ -215,19 +257,14 @@ static void wait_for_devices(struct xenbus_driver *xendrv)
 	if (!ready_to_wait_for_devices || !xen_domain())
 		return;
 
-	while (exists_connecting_device(drv)) {
-		if (time_after(jiffies, start + (seconds_waited+5)*HZ)) {
-			if (!seconds_waited)
-				printk(KERN_WARNING "XENBUS: Waiting for "
-				       "devices to initialise: ");
-			seconds_waited += 5;
-			printk("%us...", 300 - seconds_waited);
-			if (seconds_waited == 300)
-				break;
-		}
+	while (exists_non_essential_connecting_device(drv))
+		if (wait_loop(start, 30, &seconds_waited))
+			break;
 
-		schedule_timeout_interruptible(HZ/10);
-	}
+	/* Skips PVKB and PVFB check.*/
+	while (exists_essential_connecting_device(drv))
+		if (wait_loop(start, 270, &seconds_waited))
+			break;
 
 	if (seconds_waited)
 		printk("\n");