Index: linux-2.6.13/arch/i386/kernel/ldt.c
==================================================================---
linux-2.6.13.orig/arch/i386/kernel/ldt.c 2005-08-08 15:27:26.000000000 -0700
+++ linux-2.6.13/arch/i386/kernel/ldt.c 2005-08-08 21:13:19.000000000 -0700
@@ -18,6 +18,7 @@
#include <asm/system.h>
#include <asm/ldt.h>
#include <asm/desc.h>
+#include <hypervisor_hooks.h>
#ifdef CONFIG_SMP /* avoids "defined but not used" warnig */
static void flush_ldt(void *null)
@@ -58,16 +59,22 @@
#ifdef CONFIG_SMP
cpumask_t mask;
preempt_disable();
+ make_pages_readonly(pc->ldt, (pc->size * LDT_ENTRY_SIZE) /
+ PAGE_SIZE);
load_LDT(pc);
mask = cpumask_of_cpu(smp_processor_id());
if (!cpus_equal(current->mm->cpu_vm_mask, mask))
smp_call_function(flush_ldt, NULL, 1, 1);
preempt_enable();
#else
+ make_pages_readonly(pc->ldt, (pc->size * LDT_ENTRY_SIZE) /
+ PAGE_SIZE);
load_LDT(pc);
#endif
}
if (oldsize) {
+ make_pages_writable(oldldt, (oldsize * LDT_ENTRY_SIZE) /
+ PAGE_SIZE);
if (oldsize*LDT_ENTRY_SIZE > PAGE_SIZE)
vfree(oldldt);
else
@@ -82,6 +89,8 @@
if (err < 0)
return err;
memcpy(new->ldt, old->ldt, old->size*LDT_ENTRY_SIZE);
+ make_pages_readonly(new->ldt, (new->size * LDT_ENTRY_SIZE) /
+ PAGE_SIZE);
return 0;
}
@@ -94,14 +103,16 @@
struct mm_struct * old_mm;
int retval = 0;
+ memset(&mm->context, 0, sizeof(mm->context));
init_MUTEX(&mm->context.sem);
- mm->context.size = 0;
old_mm = current->mm;
if (old_mm && old_mm->context.size > 0) {
down(&old_mm->context.sem);
retval = copy_ldt(&mm->context, &old_mm->context);
up(&old_mm->context.sem);
}
+ if (retval == 0)
+ add_context_to_unpinned(mm);
return retval;
}
@@ -113,12 +124,16 @@
if (mm->context.size) {
if (mm == current->active_mm)
clear_LDT();
+ make_pages_writable(mm->context.ldt,
+ (mm->context.size * LDT_ENTRY_SIZE) /
+ PAGE_SIZE);
if (mm->context.size*LDT_ENTRY_SIZE > PAGE_SIZE)
vfree(mm->context.ldt);
else
kfree(mm->context.ldt);
mm->context.size = 0;
}
+ del_context_from_unpinned(mm);
}
static int read_ldt(void __user * ptr, unsigned long bytecount)
Index: linux-2.6.13/include/asm-i386/mach-default/hypervisor_hooks.h
==================================================================---
linux-2.6.13.orig/include/asm-i386/mach-default/hypervisor_hooks.h 2005-08-08
21:12:55.000000000 -0700
+++ linux-2.6.13/include/asm-i386/mach-default/hypervisor_hooks.h 2005-08-08
21:13:19.000000000 -0700
@@ -0,0 +1,27 @@
+#ifndef __ASM_HYPERVISOR_HOOKS_H
+#define __ASM_HYPERVISOR_HOOKS_H
+
+static inline void make_pages_readonly(void *va, unsigned int nr)
+{
+}
+
+static inline void make_pages_writable(void *va, unsigned int nr)
+{
+}
+
+static inline void add_context_to_unpinned(struct mm_struct *mm)
+{
+}
+
+static inline void del_context_from_unpinned(struct mm_struct *mm)
+{
+}
+
+static inline int install_ldt_entry (__u32 *lp, __u32 entry_1, __u32 entry_2)
+{
+ *lp = entry_1;
+ *(lp+1) = entry_2;
+ return 0;
+}
+
+#endif /* __ASM_HYPERVISOR_HOOKS_H */
Index: linux-2.6.13/include/asm-i386/mach-xen/hypervisor_hooks.h
==================================================================---
linux-2.6.13.orig/include/asm-i386/mach-xen/hypervisor_hooks.h 2005-08-08
21:12:55.000000000 -0700
+++ linux-2.6.13/include/asm-i386/mach-xen/hypervisor_hooks.h 2005-08-08
21:13:19.000000000 -0700
@@ -0,0 +1,27 @@
+#ifndef __ASM_HYPERVISOR_HOOKS_H
+#define __ASM_HYPERVISOR_HOOKS_H
+
+static inline void add_context_to_unpinned(struct mm_struct *mm)
+{
+ spin_lock(&mm_unpinned_lock);
+ list_add(&mm->context.unpinned, &mm_unpinned);
+ spin_unlock(&mm_unpinned_lock);
+}
+
+static inline void del_context_from_unpinned(struct mm_struct *mm)
+{
+ if (!mm->context.pinned) {
+ spin_lock(&mm_unpinned_lock);
+ list_del(&mm->context.unpinned);
+ spin_unlock(&mm_unpinned_lock);
+ }
+}
+
+static inline int install_ldt_entry (__u32 *lp, __u32 entry_1, __u32 entry_2)
+{
+ unsigned long mach_lp = arbitrary_virt_to_machine(lp);
+
+ return HYPERVISOR_update_descriptor(mach_lp, entry_1, entry_2);
+}
+
+#endif /* __ASM_HYPERVISOR_HOOKS_H */
