As it turns out, mapping_info DOES need to be initialized every
time. Without this, page tables were not being corrected updated, which
could cause reboots when a physical address beyond 2G was chosen.
Signed-off-by: Kees Cook <keesc...@chromium.org>
---
arch/x86/boot/compressed/pagetable.c | 16 +++++-----------
1 file changed, 5 insertions(+), 11 deletions(-)
diff --git a/arch/x86/boot/compressed/pagetable.c
b/arch/x86/boot/compressed/pagetable.c
index 3c99051566a9..34b95df14e69 100644
--- a/arch/x86/boot/compressed/pagetable.c
+++ b/arch/x86/boot/compressed/pagetable.c
@@ -90,23 +90,17 @@ static void prepare_level4(void)
}
/*
- * Mapping information structure passed to kernel_ident_mapping_init().
- * Since this never changes, there's no reason to repeatedly fill it
- * in on the stack when calling add_identity_map().
- */
-static struct x86_mapping_info mapping_info = {
- .alloc_pgt_page = alloc_pgt_page,
- .context = &pgt_data,
- .pmd_flag = __PAGE_KERNEL_LARGE_EXEC,
-};
-
-/*
* Adds the specified range to what will become the new identity mappings.
* Once all ranges have been added, the new mapping is activated by calling
* finalize_identity_maps() below.
*/
void add_identity_map(unsigned long start, unsigned long size)
{
+ struct x86_mapping_info mapping_info = {
+ .alloc_pgt_page = alloc_pgt_page,
+ .context = &pgt_data,
+ .pmd_flag = __PAGE_KERNEL_LARGE_EXEC,
+ };
unsigned long end = start + size;
/* Make sure we have a top level page table ready to use. */
--
2.6.3
