taint: add explicit flag to show whether lock dep is still OK.

Fix up all callers as they were before, with make one change: an
unsigned module taints the kernel, but doesn't turn off lockdep.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

mm/memory.c

@@ -716,7 +716,7 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
 		print_symbol(KERN_ALERT "vma->vm_file->f_op->mmap: %s\n",
 				(unsigned long)vma->vm_file->f_op->mmap);
 	dump_stack();
-	add_taint(TAINT_BAD_PAGE);
+	add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
 }
 
 static inline bool is_cow_mapping(vm_flags_t flags)

mm/page_alloc.c

@@ -320,7 +320,7 @@ static void bad_page(struct page *page)
 out:
 	/* Leave bad fields for debug, except PageBuddy could make trouble */
 	reset_page_mapcount(page); /* remove PageBuddy */
-	add_taint(TAINT_BAD_PAGE);
+	add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
 }
 
 /*

mm/slab.c

@@ -812,7 +812,7 @@ static void __slab_error(const char *function, struct kmem_cache *cachep,
 	printk(KERN_ERR "slab error in %s(): cache `%s': %s\n",
 	       function, cachep->name, msg);
 	dump_stack();
-	add_taint(TAINT_BAD_PAGE);
+	add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
 }
 #endif
 

mm/slub.c

@@ -562,7 +562,7 @@ static void slab_bug(struct kmem_cache *s, char *fmt, ...)
 	printk(KERN_ERR "----------------------------------------"
 			"-------------------------------------\n\n");
 
-	add_taint(TAINT_BAD_PAGE);
+	add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
 }
 
 static void slab_fix(struct kmem_cache *s, char *fmt, ...)