5 files changed, 64 insertions, 57 deletions

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index e0140923062f..39928d16be3b 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1637,6 +1637,7 @@ const struct hypervisor_x86 x86_hyper_xen_hvm __refconst = {
 	.name			= "Xen HVM",
 	.detect			= xen_hvm_platform,
 	.init_platform		= xen_hvm_guest_init,
+	.x2apic_available	= xen_x2apic_para_available,
 };
 EXPORT_SYMBOL(x86_hyper_xen_hvm);
 #endif
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 01de35c77221..e8e34938c57d 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -1178,20 +1178,6 @@ static void xen_exit_mmap(struct mm_struct *mm)
 
 static void xen_post_allocator_init(void);
 
-static __init void xen_mapping_pagetable_reserve(u64 start, u64 end)
-{
-	/* reserve the range used */
-	native_pagetable_reserve(start, end);
-
-	/* set as RW the rest */
-	printk(KERN_DEBUG "xen: setting RW the range %llx - %llx\n", end,
-			PFN_PHYS(pgt_buf_top));
-	while (end < PFN_PHYS(pgt_buf_top)) {
-		make_lowmem_page_readwrite(__va(end));
-		end += PAGE_SIZE;
-	}
-}
-
 #ifdef CONFIG_X86_64
 static void __init xen_cleanhighmap(unsigned long vaddr,
 				    unsigned long vaddr_end)
@@ -1422,7 +1408,6 @@ static void __xen_write_cr3(bool kernel, unsigned long cr3)
 		xen_mc_callback(set_current_cr3, (void *)cr3);
 	}
 }
-
 static void xen_write_cr3(unsigned long cr3)
 {
 	BUG_ON(preemptible());
@@ -1448,6 +1433,45 @@ static void xen_write_cr3(unsigned long cr3)
 	xen_mc_issue(PARAVIRT_LAZY_CPU);  /* interrupts restored */
 }
 
+#ifdef CONFIG_X86_64
+/*
+ * At the start of the day - when Xen launches a guest, it has already
+ * built pagetables for the guest. We diligently look over them
+ * in xen_setup_kernel_pagetable and graft as appropiate them in the
+ * init_level4_pgt and its friends. Then when we are happy we load
+ * the new init_level4_pgt - and continue on.
+ *
+ * The generic code starts (start_kernel) and 'init_mem_mapping' sets
+ * up the rest of the pagetables. When it has completed it loads the cr3.
+ * N.B. that baremetal would start at 'start_kernel' (and the early
+ * #PF handler would create bootstrap pagetables) - so we are running
+ * with the same assumptions as what to do when write_cr3 is executed
+ * at this point.
+ *
+ * Since there are no user-page tables at all, we have two variants
+ * of xen_write_cr3 - the early bootup (this one), and the late one
+ * (xen_write_cr3). The reason we have to do that is that in 64-bit
+ * the Linux kernel and user-space are both in ring 3 while the
+ * hypervisor is in ring 0.
+ */
+static void __init xen_write_cr3_init(unsigned long cr3)
+{
+	BUG_ON(preemptible());
+
+	xen_mc_batch();  /* disables interrupts */
+
+	/* Update while interrupts are disabled, so its atomic with
+	   respect to ipis */
+	this_cpu_write(xen_cr3, cr3);
+
+	__xen_write_cr3(true, cr3);
+
+	xen_mc_issue(PARAVIRT_LAZY_CPU);  /* interrupts restored */
+
+	pv_mmu_ops.write_cr3 = &xen_write_cr3;
+}
+#endif
+
 static int xen_pgd_alloc(struct mm_struct *mm)
 {
 	pgd_t *pgd = mm->pgd;
@@ -1503,19 +1527,6 @@ static pte_t __init mask_rw_pte(pte_t *ptep, pte_t pte)
 #else /* CONFIG_X86_64 */
 static pte_t __init mask_rw_pte(pte_t *ptep, pte_t pte)
 {
-	unsigned long pfn = pte_pfn(pte);
-
-	/*
-	 * If the new pfn is within the range of the newly allocated
-	 * kernel pagetable, and it isn't being mapped into an
-	 * early_ioremap fixmap slot as a freshly allocated page, make sure
-	 * it is RO.
-	 */
-	if (((!is_early_ioremap_ptep(ptep) &&
-			pfn >= pgt_buf_start && pfn < pgt_buf_top)) ||
-			(is_early_ioremap_ptep(ptep) && pfn != (pgt_buf_end - 1)))
-		pte = pte_wrprotect(pte);
-
 	return pte;
 }
 #endif /* CONFIG_X86_64 */
@@ -2129,11 +2140,7 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
 	.write_cr2 = xen_write_cr2,
 
 	.read_cr3 = xen_read_cr3,
-#ifdef CONFIG_X86_32
 	.write_cr3 = xen_write_cr3_init,
-#else
-	.write_cr3 = xen_write_cr3,
-#endif
 
 	.flush_tlb_user = xen_flush_tlb,
 	.flush_tlb_kernel = xen_flush_tlb,
@@ -2197,7 +2204,6 @@ static const struct pv_mmu_ops xen_mmu_ops __initconst = {
 
 void __init xen_init_mmu_ops(void)
 {
-	x86_init.mapping.pagetable_reserve = xen_mapping_pagetable_reserve;
 	x86_init.paging.pagetable_init = xen_pagetable_init;
 	pv_mmu_ops = xen_mmu_ops;
 
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 8971a26d21ab..94eac5c85cdc 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -556,12 +556,9 @@ void __init xen_arch_setup(void)
 	       COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE);
 
 	/* Set up idle, making sure it calls safe_halt() pvop */
-#ifdef CONFIG_X86_32
-	boot_cpu_data.hlt_works_ok = 1;
-#endif
 	disable_cpuidle();
 	disable_cpufreq();
-	WARN_ON(set_pm_idle_to_default());
+	WARN_ON(xen_set_default_idle());
 	fiddle_vdso();
 #ifdef CONFIG_NUMA
 	numa_off = 1;
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 34bc4cee8887..09ea61d2e02f 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -300,8 +300,6 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
 	gdt = get_cpu_gdt_table(cpu);
 
 	ctxt->flags = VGCF_IN_KERNEL;
-	ctxt->user_regs.ds = __USER_DS;
-	ctxt->user_regs.es = __USER_DS;
 	ctxt->user_regs.ss = __KERNEL_DS;
 #ifdef CONFIG_X86_32
 	ctxt->user_regs.fs = __KERNEL_PERCPU;
@@ -310,35 +308,41 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
 	ctxt->gs_base_kernel = per_cpu_offset(cpu);
 #endif
 	ctxt->user_regs.eip = (unsigned long)cpu_bringup_and_idle;
-	ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */
 
 	memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt));
 
-	xen_copy_trap_info(ctxt->trap_ctxt);
+	{
+		ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */
+		ctxt->user_regs.ds = __USER_DS;
+		ctxt->user_regs.es = __USER_DS;
 
-	ctxt->ldt_ents = 0;
+		xen_copy_trap_info(ctxt->trap_ctxt);
 
-	BUG_ON((unsigned long)gdt & ~PAGE_MASK);
+		ctxt->ldt_ents = 0;
 
-	gdt_mfn = arbitrary_virt_to_mfn(gdt);
-	make_lowmem_page_readonly(gdt);
-	make_lowmem_page_readonly(mfn_to_virt(gdt_mfn));
+		BUG_ON((unsigned long)gdt & ~PAGE_MASK);
 
-	ctxt->gdt_frames[0] = gdt_mfn;
-	ctxt->gdt_ents      = GDT_ENTRIES;
+		gdt_mfn = arbitrary_virt_to_mfn(gdt);
+		make_lowmem_page_readonly(gdt);
+		make_lowmem_page_readonly(mfn_to_virt(gdt_mfn));
 
-	ctxt->user_regs.cs = __KERNEL_CS;
-	ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs);
+		ctxt->gdt_frames[0] = gdt_mfn;
+		ctxt->gdt_ents      = GDT_ENTRIES;
 
-	ctxt->kernel_ss = __KERNEL_DS;
-	ctxt->kernel_sp = idle->thread.sp0;
+		ctxt->kernel_ss = __KERNEL_DS;
+		ctxt->kernel_sp = idle->thread.sp0;
 
 #ifdef CONFIG_X86_32
-	ctxt->event_callback_cs     = __KERNEL_CS;
-	ctxt->failsafe_callback_cs  = __KERNEL_CS;
+		ctxt->event_callback_cs     = __KERNEL_CS;
+		ctxt->failsafe_callback_cs  = __KERNEL_CS;
 #endif
-	ctxt->event_callback_eip    = (unsigned long)xen_hypervisor_callback;
-	ctxt->failsafe_callback_eip = (unsigned long)xen_failsafe_callback;
+		ctxt->event_callback_eip    =
+					(unsigned long)xen_hypervisor_callback;
+		ctxt->failsafe_callback_eip =
+					(unsigned long)xen_failsafe_callback;
+	}
+	ctxt->user_regs.cs = __KERNEL_CS;
+	ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs);
 
 	per_cpu(xen_cr3, cpu) = __pa(swapper_pg_dir);
 	ctxt->ctrlreg[3] = xen_pfn_to_cr3(virt_to_mfn(swapper_pg_dir));
diff --git a/arch/x86/xen/spinlock.c b/arch/x86/xen/spinlock.c
index 83e866d714ce..f7a080ef0354 100644
--- a/arch/x86/xen/spinlock.c
+++ b/arch/x86/xen/spinlock.c
@@ -328,7 +328,6 @@ static noinline void xen_spin_unlock_slow(struct xen_spinlock *xl)
 		if (per_cpu(lock_spinners, cpu) == xl) {
 			ADD_STATS(released_slow_kicked, 1);
 			xen_send_IPI_one(cpu, XEN_SPIN_UNLOCK_VECTOR);
-			break;
 		}
 	}
 }