Merge tag 'for-linus-4.20a-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:

 - A revert of a previous commit as it is no longer necessary and has
   shown to cause problems in some memory hotplug cases.

 - Some small fixes and a minor cleanup.

 - A patch for adding better diagnostic data in a very rare failure
   case.

* tag 'for-linus-4.20a-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  pvcalls-front: fixes incorrect error handling
  Revert "xen/balloon: Mark unallocated host memory as UNUSABLE"
  xen: xlate_mmu: add missing header to fix 'W=1' warning
  xen/x86: add diagnostic printout to xen_mc_flush() in case of error
  x86/xen: cleanup includes in arch/x86/xen/spinlock.c

1 files changed, 9 insertions, 56 deletions

diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index fdfc64f5acea..221b7333d067 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -251,25 +251,10 @@ static void release_memory_resource(struct resource *resource)
 	kfree(resource);
 }
 
-/*
- * Host memory not allocated to dom0. We can use this range for hotplug-based
- * ballooning.
- *
- * It's a type-less resource. Setting IORESOURCE_MEM will make resource
- * management algorithms (arch_remove_reservations()) look into guest e820,
- * which we don't want.
- */
-static struct resource hostmem_resource = {
-	.name   = "Host RAM",
-};
-
-void __attribute__((weak)) __init arch_xen_balloon_init(struct resource *res)
-{}
-
 static struct resource *additional_memory_resource(phys_addr_t size)
 {
-	struct resource *res, *res_hostmem;
-	int ret = -ENOMEM;
+	struct resource *res;
+	int ret;
 
 	res = kzalloc(sizeof(*res), GFP_KERNEL);
 	if (!res)
@@ -278,42 +263,13 @@ static struct resource *additional_memory_resource(phys_addr_t size)
 	res->name = "System RAM";
 	res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 
-	res_hostmem = kzalloc(sizeof(*res), GFP_KERNEL);
-	if (res_hostmem) {
-		/* Try to grab a range from hostmem */
-		res_hostmem->name = "Host memory";
-		ret = allocate_resource(&hostmem_resource, res_hostmem,
-					size, 0, -1,
-					PAGES_PER_SECTION * PAGE_SIZE, NULL, NULL);
-	}
-
-	if (!ret) {
-		/*
-		 * Insert this resource into iomem. Because hostmem_resource
-		 * tracks portion of guest e820 marked as UNUSABLE noone else
-		 * should try to use it.
-		 */
-		res->start = res_hostmem->start;
-		res->end = res_hostmem->end;
-		ret = insert_resource(&iomem_resource, res);
-		if (ret < 0) {
-			pr_err("Can't insert iomem_resource [%llx - %llx]\n",
-				res->start, res->end);
-			release_memory_resource(res_hostmem);
-			res_hostmem = NULL;
-			res->start = res->end = 0;
-		}
-	}
-
-	if (ret) {
-		ret = allocate_resource(&iomem_resource, res,
-					size, 0, -1,
-					PAGES_PER_SECTION * PAGE_SIZE, NULL, NULL);
-		if (ret < 0) {
-			pr_err("Cannot allocate new System RAM resource\n");
-			kfree(res);
-			return NULL;
-		}
+	ret = allocate_resource(&iomem_resource, res,
+				size, 0, -1,
+				PAGES_PER_SECTION * PAGE_SIZE, NULL, NULL);
+	if (ret < 0) {
+		pr_err("Cannot allocate new System RAM resource\n");
+		kfree(res);
+		return NULL;
 	}
 
 #ifdef CONFIG_SPARSEMEM
@@ -325,7 +281,6 @@ static struct resource *additional_memory_resource(phys_addr_t size)
 			pr_err("New System RAM resource outside addressable RAM (%lu > %lu)\n",
 			       pfn, limit);
 			release_memory_resource(res);
-			release_memory_resource(res_hostmem);
 			return NULL;
 		}
 	}
@@ -750,8 +705,6 @@ static int __init balloon_init(void)
 	set_online_page_callback(&xen_online_page);
 	register_memory_notifier(&xen_memory_nb);
 	register_sysctl_table(xen_root);
-
-	arch_xen_balloon_init(&hostmem_resource);
 #endif
 
 #ifdef CONFIG_XEN_PV