[linux-pm] [PATCH] Don't explode on swsusp failure to find swap

[benh at kernel.crashing.org (Benjamin Herrenschmidt)]

Hi !

If we specify a swap device for swsusp using resume= kernel argument and
that device doesn't exist in the swap list, we end up calling
swsusp_free() before we have allocated pagedir_save. That causes us to
explode when trying to free it.

Pavel, does that look right ?

Signed-off-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>

Index: linux-work/kernel/power/swsusp.c
===================================================================
--- linux-work.orig/kernel/power/swsusp.c	2005-05-31 16:29:22.000000000 +1000
+++ linux-work/kernel/power/swsusp.c	2005-05-31 16:57:30.000000000 +1000
@@ -730,10 +730,13 @@
 
 void swsusp_free(void)
 {
+	if (pagedir_save == NULL)
+		return;
 	BUG_ON(PageNosave(virt_to_page(pagedir_save)));
 	BUG_ON(PageNosaveFree(virt_to_page(pagedir_save)));
 	free_image_pages();
 	free_pagedir(pagedir_save);
+	pagedir_save = NULL;
 }