Merged.

linux-2.6-xen-sparse/arch/xen/i386/mm/fault.c

@@ -209,7 +209,10 @@ static void dump_fault_path(unsigned long address)
 {
 	unsigned long *p, page;
 
-        page = __pa(per_cpu(cur_pgd, smp_processor_id()));
+	preempt_disable();
+	page = __pa(per_cpu(cur_pgd, smp_processor_id()));
+	preempt_enable();
+
 	p  = (unsigned long *)__va(page);
 	p += (address >> 30) * 2;
 	printk(KERN_ALERT "%08lx -> *pde = %08lx:%08lx\n", page, p[1], p[0]);
@@ -237,8 +240,13 @@ static void dump_fault_path(unsigned long address)
 {
 	unsigned long page;
 
+	preempt_disable();
 	page = ((unsigned long *) per_cpu(cur_pgd, smp_processor_id()))
 	    [address >> 22];
+	preempt_enable();
+
+	page = ((unsigned long *) per_cpu(cur_pgd, get_cpu()))
+	    [address >> 22];
 	printk(KERN_ALERT "*pde = ma %08lx pa %08lx\n", page,
 	       machine_to_phys(page));
 	/*
@@ -567,7 +575,9 @@ vmalloc_fault:
 		pmd_t *pmd, *pmd_k;
 		pte_t *pte_k;
 
+		preempt_disable();
 		pgd = index + per_cpu(cur_pgd, smp_processor_id());
+		preempt_enable();
 		pgd_k = init_mm.pgd + index;
 
 		if (!pgd_present(*pgd_k))

linux-2.6-xen-sparse/arch/xen/x86_64/mm/fault.c

@@ -149,7 +149,9 @@ void dump_pagetable(unsigned long address)
 	pmd_t *pmd;
 	pte_t *pte;
 
+	preempt_disable();
 	pgd = (pgd_t *)per_cpu(cur_pgd, smp_processor_id());
+	preempt_enable();
 	pgd += pgd_index(address);
 
 	printk("PGD %lx ", pgd_val(*pgd));
@@ -252,7 +254,9 @@ static int vmalloc_fault(unsigned long address)
 
 	/* On Xen the line below does not always work. Needs investigating! */
 	/*pgd = pgd_offset(current->mm ?: &init_mm, address);*/
+	preempt_disable();
 	pgd = (pgd_t *)per_cpu(cur_pgd, smp_processor_id());
+	preempt_enable();
 	pgd += pgd_index(address);
 
 	pgd_ref = pgd_offset_k(address);