[tip:x86/mm] x86/mm: Fix dump pagetables for 4 levels of page tables

From: tip-bot for Juergen Gross
Date: Wed Apr 12 2017 - 18:33:07 EST


Commit-ID: 84bbabc3a452e8085cfbd745ff0bff2b89074417
Gitweb: http://git.kernel.org/tip/84bbabc3a452e8085cfbd745ff0bff2b89074417
Author: Juergen Gross <jgross@xxxxxxxx>
AuthorDate: Wed, 12 Apr 2017 16:36:34 +0200
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Thu, 13 Apr 2017 00:26:30 +0200

x86/mm: Fix dump pagetables for 4 levels of page tables

Commit fdd3d8ce0ea62 ("x86/dump_pagetables: Add support for 5-level
paging") introduced an error for dumping with only 4 levels by setting
PGD_LEVEL_MULT to a wrong value.

This is leading to e.g. addresses printed as "(null)" for ranges:

x86/mm: Found insecure W+X mapping at address (null)/(null)

Make PGD_LEVEL_MULT a multiple of PTRS_PER_P4D instead of PTRS_PER_PUD

Fixes: fdd3d8ce0ea62 ("x86/dump_pagetables: Add support for 5-level paging")
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/20170412143634.6846-1-jgross@xxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

---
arch/x86/mm/dump_pagetables.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c
index 9f305be..bce6990 100644
--- a/arch/x86/mm/dump_pagetables.c
+++ b/arch/x86/mm/dump_pagetables.c
@@ -111,7 +111,7 @@ static struct addr_marker address_markers[] = {
#define PMD_LEVEL_MULT (PTRS_PER_PTE * PTE_LEVEL_MULT)
#define PUD_LEVEL_MULT (PTRS_PER_PMD * PMD_LEVEL_MULT)
#define P4D_LEVEL_MULT (PTRS_PER_PUD * PUD_LEVEL_MULT)
-#define PGD_LEVEL_MULT (PTRS_PER_PUD * P4D_LEVEL_MULT)
+#define PGD_LEVEL_MULT (PTRS_PER_P4D * P4D_LEVEL_MULT)

#define pt_dump_seq_printf(m, to_dmesg, fmt, args...) \
({ \