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
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index e996e8e..750f46a 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -10,7 +10,6 @@
 #include <xen/xen.h>
 #include <xen/features.h>
 #include <xen/page.h>
-#include <xen/interface/memory.h>
 
 #include <asm/xen/hypercall.h>
 #include <asm/xen/hypervisor.h>
@@ -346,80 +345,3 @@
 }
 EXPORT_SYMBOL(xen_arch_unregister_cpu);
 #endif
-
-#ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
-void __init arch_xen_balloon_init(struct resource *hostmem_resource)
-{
-	struct xen_memory_map memmap;
-	int rc;
-	unsigned int i, last_guest_ram;
-	phys_addr_t max_addr = PFN_PHYS(max_pfn);
-	struct e820_table *xen_e820_table;
-	const struct e820_entry *entry;
-	struct resource *res;
-
-	if (!xen_initial_domain())
-		return;
-
-	xen_e820_table = kmalloc(sizeof(*xen_e820_table), GFP_KERNEL);
-	if (!xen_e820_table)
-		return;
-
-	memmap.nr_entries = ARRAY_SIZE(xen_e820_table->entries);
-	set_xen_guest_handle(memmap.buffer, xen_e820_table->entries);
-	rc = HYPERVISOR_memory_op(XENMEM_machine_memory_map, &memmap);
-	if (rc) {
-		pr_warn("%s: Can't read host e820 (%d)\n", __func__, rc);
-		goto out;
-	}
-
-	last_guest_ram = 0;
-	for (i = 0; i < memmap.nr_entries; i++) {
-		if (xen_e820_table->entries[i].addr >= max_addr)
-			break;
-		if (xen_e820_table->entries[i].type == E820_TYPE_RAM)
-			last_guest_ram = i;
-	}
-
-	entry = &xen_e820_table->entries[last_guest_ram];
-	if (max_addr >= entry->addr + entry->size)
-		goto out; /* No unallocated host RAM. */
-
-	hostmem_resource->start = max_addr;
-	hostmem_resource->end = entry->addr + entry->size;
-
-	/*
-	 * Mark non-RAM regions between the end of dom0 RAM and end of host RAM
-	 * as unavailable. The rest of that region can be used for hotplug-based
-	 * ballooning.
-	 */
-	for (; i < memmap.nr_entries; i++) {
-		entry = &xen_e820_table->entries[i];
-
-		if (entry->type == E820_TYPE_RAM)
-			continue;
-
-		if (entry->addr >= hostmem_resource->end)
-			break;
-
-		res = kzalloc(sizeof(*res), GFP_KERNEL);
-		if (!res)
-			goto out;
-
-		res->name = "Unavailable host RAM";
-		res->start = entry->addr;
-		res->end = (entry->addr + entry->size < hostmem_resource->end) ?
-			    entry->addr + entry->size : hostmem_resource->end;
-		rc = insert_resource(hostmem_resource, res);
-		if (rc) {
-			pr_warn("%s: Can't insert [%llx - %llx) (%d)\n",
-				__func__, res->start, res->end, rc);
-			kfree(res);
-			goto  out;
-		}
-	}
-
- out:
-	kfree(xen_e820_table);
-}
-#endif /* CONFIG_XEN_BALLOON_MEMORY_HOTPLUG */
diff --git a/arch/x86/xen/multicalls.c b/arch/x86/xen/multicalls.c
index 2bce795..0766a08 100644
--- a/arch/x86/xen/multicalls.c
+++ b/arch/x86/xen/multicalls.c
@@ -69,6 +69,11 @@
 
 	trace_xen_mc_flush(b->mcidx, b->argidx, b->cbidx);
 
+#if MC_DEBUG
+	memcpy(b->debug, b->entries,
+	       b->mcidx * sizeof(struct multicall_entry));
+#endif
+
 	switch (b->mcidx) {
 	case 0:
 		/* no-op */
@@ -87,32 +92,34 @@
 		break;
 
 	default:
-#if MC_DEBUG
-		memcpy(b->debug, b->entries,
-		       b->mcidx * sizeof(struct multicall_entry));
-#endif
-
 		if (HYPERVISOR_multicall(b->entries, b->mcidx) != 0)
 			BUG();
 		for (i = 0; i < b->mcidx; i++)
 			if (b->entries[i].result < 0)
 				ret++;
+	}
 
+	if (WARN_ON(ret)) {
+		pr_err("%d of %d multicall(s) failed: cpu %d\n",
+		       ret, b->mcidx, smp_processor_id());
+		for (i = 0; i < b->mcidx; i++) {
+			if (b->entries[i].result < 0) {
 #if MC_DEBUG
-		if (ret) {
-			printk(KERN_ERR "%d multicall(s) failed: cpu %d\n",
-			       ret, smp_processor_id());
-			dump_stack();
-			for (i = 0; i < b->mcidx; i++) {
-				printk(KERN_DEBUG "  call %2d/%d: op=%lu arg=[%lx] result=%ld\t%pF\n",
-				       i+1, b->mcidx,
+				pr_err("  call %2d: op=%lu arg=[%lx] result=%ld\t%pF\n",
+				       i + 1,
 				       b->debug[i].op,
 				       b->debug[i].args[0],
 				       b->entries[i].result,
 				       b->caller[i]);
+#else
+				pr_err("  call %2d: op=%lu arg=[%lx] result=%ld\n",
+				       i + 1,
+				       b->entries[i].op,
+				       b->entries[i].args[0],
+				       b->entries[i].result);
+#endif
 			}
 		}
-#endif
 	}
 
 	b->mcidx = 0;
@@ -126,8 +133,6 @@
 	b->cbidx = 0;
 
 	local_irq_restore(flags);
-
-	WARN_ON(ret);
 }
 
 struct multicall_space __xen_mc_entry(size_t args)
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 1163e33..075ed47 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -808,6 +808,7 @@
 	addr = xen_e820_table.entries[0].addr;
 	size = xen_e820_table.entries[0].size;
 	while (i < xen_e820_table.nr_entries) {
+		bool discard = false;
 
 		chunk_size = size;
 		type = xen_e820_table.entries[i].type;
@@ -823,10 +824,11 @@
 				xen_add_extra_mem(pfn_s, n_pfns);
 				xen_max_p2m_pfn = pfn_s + n_pfns;
 			} else
-				type = E820_TYPE_UNUSABLE;
+				discard = true;
 		}
 
-		xen_align_and_add_e820_region(addr, chunk_size, type);
+		if (!discard)
+			xen_align_and_add_e820_region(addr, chunk_size, type);
 
 		addr += chunk_size;
 		size -= chunk_size;
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 1c8a881..3776122 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -3,22 +3,17 @@
  * Split spinlock implementation out into its own file, so it can be
  * compiled in a FTRACE-compatible way.
  */
-#include <linux/kernel_stat.h>
+#include <linux/kernel.h>
 #include <linux/spinlock.h>
-#include <linux/debugfs.h>
-#include <linux/log2.h>
-#include <linux/gfp.h>
 #include <linux/slab.h>
 #include <linux/atomic.h>
 
 #include <asm/paravirt.h>
 #include <asm/qspinlock.h>
 
-#include <xen/interface/xen.h>
 #include <xen/events.h>
 
 #include "xen-ops.h"
-#include "debugfs.h"
 
 static DEFINE_PER_CPU(int, lock_kicker_irq) = -1;
 static DEFINE_PER_CPU(char *, irq_name);
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index fdfc64f..221b733 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -251,25 +251,10 @@
 	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 @@
 	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 @@
 			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 @@
 	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
diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c
index 2f11ca7..77224d8 100644
--- a/drivers/xen/pvcalls-front.c
+++ b/drivers/xen/pvcalls-front.c
@@ -385,8 +385,8 @@
 out_error:
 	if (*evtchn >= 0)
 		xenbus_free_evtchn(pvcalls_front_dev, *evtchn);
-	kfree(map->active.data.in);
-	kfree(map->active.ring);
+	free_pages((unsigned long)map->active.data.in, PVCALLS_RING_ORDER);
+	free_page((unsigned long)map->active.ring);
 	return ret;
 }
 
diff --git a/drivers/xen/xlate_mmu.c b/drivers/xen/xlate_mmu.c
index 23f1387..e7df65d 100644
--- a/drivers/xen/xlate_mmu.c
+++ b/drivers/xen/xlate_mmu.c
@@ -36,6 +36,7 @@
 #include <asm/xen/hypervisor.h>
 
 #include <xen/xen.h>
+#include <xen/xen-ops.h>
 #include <xen/page.h>
 #include <xen/interface/xen.h>
 #include <xen/interface/memory.h>
diff --git a/include/xen/balloon.h b/include/xen/balloon.h
index 61f410f..4914b93 100644
--- a/include/xen/balloon.h
+++ b/include/xen/balloon.h
@@ -44,8 +44,3 @@
 {
 }
 #endif
-
-#ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
-struct resource;
-void arch_xen_balloon_init(struct resource *hostmem_resource);
-#endif