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-rw-r--r--arch/x86/kernel/ldt.c9
-rw-r--r--arch/x86/kernel/paravirt.c4
-rw-r--r--arch/x86/xen/enlighten.c60
-rw-r--r--include/asm-x86/desc.h15
-rw-r--r--include/asm-x86/paravirt.h13
5 files changed, 96 insertions, 5 deletions
diff --git a/arch/x86/kernel/ldt.c b/arch/x86/kernel/ldt.c
index 3fee2aa50f3f..4895e0634d22 100644
--- a/arch/x86/kernel/ldt.c
+++ b/arch/x86/kernel/ldt.c
@@ -51,6 +51,8 @@ static int alloc_ldt(mm_context_t *pc, int mincount, int reload)
memset(newldt + oldsize * LDT_ENTRY_SIZE, 0,
(mincount - oldsize) * LDT_ENTRY_SIZE);
+ paravirt_alloc_ldt(newldt, mincount);
+
#ifdef CONFIG_X86_64
/* CHECKME: Do we really need this ? */
wmb();
@@ -75,6 +77,7 @@ static int alloc_ldt(mm_context_t *pc, int mincount, int reload)
#endif
}
if (oldsize) {
+ paravirt_free_ldt(oldldt, oldsize);
if (oldsize * LDT_ENTRY_SIZE > PAGE_SIZE)
vfree(oldldt);
else
@@ -86,10 +89,13 @@ static int alloc_ldt(mm_context_t *pc, int mincount, int reload)
static inline int copy_ldt(mm_context_t *new, mm_context_t *old)
{
int err = alloc_ldt(new, old->size, 0);
+ int i;
if (err < 0)
return err;
- memcpy(new->ldt, old->ldt, old->size * LDT_ENTRY_SIZE);
+
+ for(i = 0; i < old->size; i++)
+ write_ldt_entry(new->ldt, i, old->ldt + i * LDT_ENTRY_SIZE);
return 0;
}
@@ -126,6 +132,7 @@ void destroy_context(struct mm_struct *mm)
if (mm == current->active_mm)
clear_LDT();
#endif
+ paravirt_free_ldt(mm->context.ldt, mm->context.size);
if (mm->context.size * LDT_ENTRY_SIZE > PAGE_SIZE)
vfree(mm->context.ldt);
else
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 94da4d52d798..d8f2277be5a0 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -348,6 +348,10 @@ struct pv_cpu_ops pv_cpu_ops = {
.write_ldt_entry = native_write_ldt_entry,
.write_gdt_entry = native_write_gdt_entry,
.write_idt_entry = native_write_idt_entry,
+
+ .alloc_ldt = paravirt_nop,
+ .free_ldt = paravirt_nop,
+
.load_sp0 = native_load_sp0,
#if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION)
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 9ff6e3cbf08f..b011e4a5dbbe 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);
@@ -1220,6 +1271,9 @@ 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 +1378,7 @@ 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/include/asm-x86/desc.h b/include/asm-x86/desc.h
index a44c4dc70590..06f786f4b4fb 100644
--- a/include/asm-x86/desc.h
+++ b/include/asm-x86/desc.h
@@ -24,6 +24,11 @@ static inline void fill_ldt(struct desc_struct *desc,
desc->d = info->seg_32bit;
desc->g = info->limit_in_pages;
desc->base2 = (info->base_addr & 0xff000000) >> 24;
+ /*
+ * Don't allow setting of the lm bit. It is useless anyway
+ * because 64bit system calls require __USER_CS:
+ */
+ desc->l = 0;
}
extern struct desc_ptr idt_descr;
@@ -97,7 +102,15 @@ static inline int desc_empty(const void *ptr)
native_write_gdt_entry(dt, entry, desc, type)
#define write_idt_entry(dt, entry, g) \
native_write_idt_entry(dt, entry, g)
-#endif
+
+static inline void paravirt_alloc_ldt(struct desc_struct *ldt, unsigned entries)
+{
+}
+
+static inline void paravirt_free_ldt(struct desc_struct *ldt, unsigned entries)
+{
+}
+#endif /* CONFIG_PARAVIRT */
static inline void native_write_idt_entry(gate_desc *idt, int entry,
const gate_desc *gate)
diff --git a/include/asm-x86/paravirt.h b/include/asm-x86/paravirt.h
index fbbde93f12d6..db9b0647b346 100644
--- a/include/asm-x86/paravirt.h
+++ b/include/asm-x86/paravirt.h
@@ -124,6 +124,9 @@ struct pv_cpu_ops {
int entrynum, const void *desc, int size);
void (*write_idt_entry)(gate_desc *,
int entrynum, const gate_desc *gate);
+ void (*alloc_ldt)(struct desc_struct *ldt, unsigned entries);
+ void (*free_ldt)(struct desc_struct *ldt, unsigned entries);
+
void (*load_sp0)(struct tss_struct *tss, struct thread_struct *t);
void (*set_iopl_mask)(unsigned mask);
@@ -824,6 +827,16 @@ do { \
(aux) = __aux; \
} while (0)
+static inline void paravirt_alloc_ldt(struct desc_struct *ldt, unsigned entries)
+{
+ PVOP_VCALL2(pv_cpu_ops.alloc_ldt, ldt, entries);
+}
+
+static inline void paravirt_free_ldt(struct desc_struct *ldt, unsigned entries)
+{
+ PVOP_VCALL2(pv_cpu_ops.free_ldt, ldt, entries);
+}
+
static inline void load_TR_desc(void)
{
PVOP_VCALL0(pv_cpu_ops.load_tr_desc);
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