2 files changed, 71 insertions, 4 deletions

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 9ff6e3cbf08f..b795470ec069 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -325,6 +325,57 @@ static unsigned long xen_store_tr(void)
         return 0;
 }
 
+/*
+ * If 'v' is a vmalloc mapping, then find the linear mapping of the
+ * page (if any) and also set its protections to match:
+ */
+static void set_aliased_prot(void *v, pgprot_t prot)
+{
+        int level;
+        pte_t *ptep;
+        pte_t pte;
+        unsigned long pfn;
+        struct page *page;
+
+        ptep = lookup_address((unsigned long)v, &level);
+        BUG_ON(ptep == NULL);
+
+        pfn = pte_pfn(*ptep);
+        page = pfn_to_page(pfn);
+
+        pte = pfn_pte(pfn, prot);
+
+        if (HYPERVISOR_update_va_mapping((unsigned long)v, pte, 0))
+                BUG();
+
+        if (!PageHighMem(page)) {
+                void *av = __va(PFN_PHYS(pfn));
+
+                if (av != v)
+                        if (HYPERVISOR_update_va_mapping((unsigned long)av, pte, 0))
+                                BUG();
+        } else
+                kmap_flush_unused();
+}
+
+static void xen_alloc_ldt(struct desc_struct *ldt, unsigned entries)
+{
+        const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
+        int i;
+
+        for(i = 0; i < entries; i += entries_per_page)
+                set_aliased_prot(ldt + i, PAGE_KERNEL_RO);
+}
+
+static void xen_free_ldt(struct desc_struct *ldt, unsigned entries)
+{
+        const unsigned entries_per_page = PAGE_SIZE / LDT_ENTRY_SIZE;
+        int i;
+
+        for(i = 0; i < entries; i += entries_per_page)
+                set_aliased_prot(ldt + i, PAGE_KERNEL);
+}
+
 static void xen_set_ldt(const void *addr, unsigned entries)
 {
         struct mmuext_op *op;
@@ -426,7 +477,7 @@ static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum,
                                 const void *ptr)
 {
         unsigned long lp = (unsigned long)&dt[entrynum];
-        xmaddr_t mach_lp = virt_to_machine(lp);
+        xmaddr_t mach_lp = arbitrary_virt_to_machine(lp);
         u64 entry = *(u64 *)ptr;
 
         preempt_disable();
@@ -559,7 +610,7 @@ static void xen_write_gdt_entry(struct desc_struct *dt, int entry,
 }
 
 static void xen_load_sp0(struct tss_struct *tss,
-                          struct thread_struct *thread)
+                         struct thread_struct *thread)
 {
         struct multicall_space mcs = xen_mc_entry(0);
         MULTI_stack_switch(mcs.mc, __KERNEL_DS, thread->sp0);
@@ -803,6 +854,19 @@ static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
                         ret = -EFAULT;
                 break;
 #endif
+
+        case MSR_STAR:
+        case MSR_CSTAR:
+        case MSR_LSTAR:
+        case MSR_SYSCALL_MASK:
+        case MSR_IA32_SYSENTER_CS:
+        case MSR_IA32_SYSENTER_ESP:
+        case MSR_IA32_SYSENTER_EIP:
+                /* Fast syscall setup is all done in hypercalls, so
+                   these are all ignored.  Stub them out here to stop
+                   Xen console noise. */
+                break;
+
         default:
                 ret = native_write_msr_safe(msr, low, high);
         }
@@ -1220,6 +1284,9 @@ static const struct pv_cpu_ops xen_cpu_ops __initdata = {
         .load_gs_index = xen_load_gs_index,
 #endif
 
+        .alloc_ldt = xen_alloc_ldt,
+        .free_ldt = xen_free_ldt,
+
         .store_gdt = native_store_gdt,
         .store_idt = native_store_idt,
         .store_tr = xen_store_tr,
@@ -1324,7 +1391,7 @@ static const struct pv_mmu_ops xen_mmu_ops __initdata = {
         .ptep_modify_prot_commit = __ptep_modify_prot_commit,
 
         .pte_val = xen_pte_val,
-        .pte_flags = native_pte_val,
+        .pte_flags = native_pte_flags,
         .pgd_val = xen_pgd_val,
 
         .make_pte = xen_make_pte,
diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S
index 4038cbfe3331..7f58304fafb3 100644
--- a/arch/x86/xen/xen-asm_64.S
+++ b/arch/x86/xen/xen-asm_64.S
@@ -173,7 +173,7 @@ ENTRY(xen_sysexit)
         pushq $__USER32_CS
         pushq %rdx
 
-        pushq $VGCF_in_syscall
+        pushq $0
 1:      jmp hypercall_iret
 ENDPATCH(xen_sysexit)
 RELOC(xen_sysexit, 1b+1)