Merge tag 'for-linus-5.1a-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:
 "xen fixes and features:

   - remove fallback code for very old Xen hypervisors

   - three patches for fixing Xen dom0 boot regressions

   - an old patch for Xen PCI passthrough which was never applied for
     unknown reasons

   - some more minor fixes and cleanup patches"

* tag 'for-linus-5.1a-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: fix dom0 boot on huge systems
  xen, cpu_hotplug: Prevent an out of bounds access
  xen: remove pre-xen3 fallback handlers
  xen/ACPI: Switch to bitmap_zalloc()
  x86/xen: dont add memory above max allowed allocation
  x86: respect memory size limiting via mem= parameter
  xen/gntdev: Check and release imported dma-bufs on close
  xen/gntdev: Do not destroy context while dma-bufs are in use
  xen/pciback: Don't disable PCI_COMMAND on PCI device reset.
  xen-scsiback: mark expected switch fall-through
  xen: mark expected switch fall-through

4 files changed, 26 insertions, 18 deletions

diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h
index ef05bea7010d..de6f0d59a24f 100644
--- a/arch/x86/include/asm/xen/hypercall.h
+++ b/arch/x86/include/asm/xen/hypercall.h
@@ -332,15 +332,11 @@ HYPERVISOR_update_va_mapping(unsigned long va, pte_t new_val,
 		return _hypercall4(int, update_va_mapping, va,
 				   new_val.pte, new_val.pte >> 32, flags);
 }
-extern int __must_check xen_event_channel_op_compat(int, void *);
 
 static inline int
 HYPERVISOR_event_channel_op(int cmd, void *arg)
 {
-	int rc = _hypercall2(int, event_channel_op, cmd, arg);
-	if (unlikely(rc == -ENOSYS))
-		rc = xen_event_channel_op_compat(cmd, arg);
-	return rc;
+	return _hypercall2(int, event_channel_op, cmd, arg);
 }
 
 static inline int
@@ -355,15 +351,10 @@ HYPERVISOR_console_io(int cmd, int count, char *str)
 	return _hypercall3(int, console_io, cmd, count, str);
 }
 
-extern int __must_check xen_physdev_op_compat(int, void *);
-
 static inline int
 HYPERVISOR_physdev_op(int cmd, void *arg)
 {
-	int rc = _hypercall2(int, physdev_op, cmd, arg);
-	if (unlikely(rc == -ENOSYS))
-		rc = xen_physdev_op_compat(cmd, arg);
-	return rc;
+	return _hypercall2(int, physdev_op, cmd, arg);
 }
 
 static inline int
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index a687d10da417..666e4af145a2 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -14,6 +14,7 @@
 #include <linux/acpi.h>
 #include <linux/firmware-map.h>
 #include <linux/sort.h>
+#include <linux/memory_hotplug.h>
 
 #include <asm/e820/api.h>
 #include <asm/setup.h>
@@ -878,6 +879,10 @@ static int __init parse_memopt(char *p)
 
 	e820__range_remove(mem_size, ULLONG_MAX - mem_size, E820_TYPE_RAM, 1);
 
+#ifdef CONFIG_MEMORY_HOTPLUG
+	max_mem_size = mem_size;
+#endif
+
 	return 0;
 }
 early_param("mem", parse_memopt);
diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c
index 856a85814f00..a21e1734fc1f 100644
--- a/arch/x86/xen/mmu_pv.c
+++ b/arch/x86/xen/mmu_pv.c
@@ -2114,10 +2114,10 @@ void __init xen_relocate_p2m(void)
 				pt = early_memremap(pt_phys, PAGE_SIZE);
 				clear_page(pt);
 				for (idx_pte = 0;
-						idx_pte < min(n_pte, PTRS_PER_PTE);
-						idx_pte++) {
-					set_pte(pt + idx_pte,
-							pfn_pte(p2m_pfn, PAGE_KERNEL));
+				     idx_pte < min(n_pte, PTRS_PER_PTE);
+				     idx_pte++) {
+					pt[idx_pte] = pfn_pte(p2m_pfn,
+							      PAGE_KERNEL);
 					p2m_pfn++;
 				}
 				n_pte -= PTRS_PER_PTE;
@@ -2125,8 +2125,7 @@ void __init xen_relocate_p2m(void)
 				make_lowmem_page_readonly(__va(pt_phys));
 				pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE,
 						PFN_DOWN(pt_phys));
-				set_pmd(pmd + idx_pt,
-						__pmd(_PAGE_TABLE | pt_phys));
+				pmd[idx_pt] = __pmd(_PAGE_TABLE | pt_phys);
 				pt_phys += PAGE_SIZE;
 			}
 			n_pt -= PTRS_PER_PMD;
@@ -2134,7 +2133,7 @@ void __init xen_relocate_p2m(void)
 			make_lowmem_page_readonly(__va(pmd_phys));
 			pin_pagetable_pfn(MMUEXT_PIN_L2_TABLE,
 					PFN_DOWN(pmd_phys));
-			set_pud(pud + idx_pmd, __pud(_PAGE_TABLE | pmd_phys));
+			pud[idx_pmd] = __pud(_PAGE_TABLE | pmd_phys);
 			pmd_phys += PAGE_SIZE;
 		}
 		n_pmd -= PTRS_PER_PUD;
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index d5f303c0e656..548d1e0a5ba1 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -12,6 +12,7 @@
 #include <linux/memblock.h>
 #include <linux/cpuidle.h>
 #include <linux/cpufreq.h>
+#include <linux/memory_hotplug.h>
 
 #include <asm/elf.h>
 #include <asm/vdso.h>
@@ -589,6 +590,14 @@ static void __init xen_align_and_add_e820_region(phys_addr_t start,
 	if (type == E820_TYPE_RAM) {
 		start = PAGE_ALIGN(start);
 		end &= ~((phys_addr_t)PAGE_SIZE - 1);
+#ifdef CONFIG_MEMORY_HOTPLUG
+		/*
+		 * Don't allow adding memory not in E820 map while booting the
+		 * system. Once the balloon driver is up it will remove that
+		 * restriction again.
+		 */
+		max_mem_size = end;
+#endif
 	}
 
 	e820__range_add(start, end - start, type);
@@ -748,6 +757,10 @@ char * __init xen_memory_setup(void)
 	memmap.nr_entries = ARRAY_SIZE(xen_e820_table.entries);
 	set_xen_guest_handle(memmap.buffer, xen_e820_table.entries);
 
+#if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_XEN_BALLOON)
+	xen_saved_max_mem_size = max_mem_size;
+#endif
+
 	op = xen_initial_domain() ?
 		XENMEM_machine_memory_map :
 		XENMEM_memory_map;