[tip:x86/mm] x86/kasan: Extend KASAN to support 5-level paging

[tip-bot for Kirill A. Shutemov]

Commit-ID:  5480bb61cfba5de23df59793527c3a37c0d2e247
Gitweb: http://git.kernel.org/tip/5480bb61cfba5de23df59793527c3a37c0d2e247
Author: Kirill A. Shutemov 
AuthorDate: Thu, 30 Mar 2017 11:07:30 +0300
Committer:  Ingo Molnar 
CommitDate: Tue, 4 Apr 2017 08:22:34 +0200

x86/kasan: Extend KASAN to support 5-level paging

This patch bring support for a non-folded additional page table level.

Signed-off-by: Kirill A. Shutemov 
Cc: Andrew Morton 
Cc: Andrey Ryabinin 
Cc: Andy Lutomirski 
Cc: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Brian Gerst 
Cc: Dave Hansen 
Cc: Denys Vlasenko 
Cc: Dmitry Vyukov 
Cc: H. Peter Anvin 
Cc: Josh Poimboeuf 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-a...@vger.kernel.org
Cc: linux...@kvack.org
Link: 
http://lkml.kernel.org/r/20170330080731.65421-7-kirill.shute...@linux.intel.com
Signed-off-by: Ingo Molnar 
---
 arch/x86/mm/kasan_init_64.c | 18 --
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/arch/x86/mm/kasan_init_64.c b/arch/x86/mm/kasan_init_64.c
index 3d1059d..47efdcf 100644
--- a/arch/x86/mm/kasan_init_64.c
+++ b/arch/x86/mm/kasan_init_64.c
@@ -55,8 +55,18 @@ static void __init kasan_map_early_shadow(pgd_t *pgd)
unsigned long end = KASAN_SHADOW_END;
 
for (i = pgd_index(start); start < end; i++) {
-   pgd[i] = __pgd(__pa_nodebug(kasan_zero_pud)
-   | _KERNPG_TABLE);
+   switch (CONFIG_PGTABLE_LEVELS) {
+   case 4:
+   pgd[i] = __pgd(__pa_nodebug(kasan_zero_pud) |
+   _KERNPG_TABLE);
+   break;
+   case 5:
+   pgd[i] = __pgd(__pa_nodebug(kasan_zero_p4d) |
+   _KERNPG_TABLE);
+   break;
+   default:
+   BUILD_BUG();
+   }
start += PGDIR_SIZE;
}
 }
@@ -84,6 +94,7 @@ void __init kasan_early_init(void)
pteval_t pte_val = __pa_nodebug(kasan_zero_page) | __PAGE_KERNEL;
pmdval_t pmd_val = __pa_nodebug(kasan_zero_pte) | _KERNPG_TABLE;
pudval_t pud_val = __pa_nodebug(kasan_zero_pmd) | _KERNPG_TABLE;
+   p4dval_t p4d_val = __pa_nodebug(kasan_zero_pud) | _KERNPG_TABLE;
 
for (i = 0; i < PTRS_PER_PTE; i++)
kasan_zero_pte[i] = __pte(pte_val);
@@ -94,6 +105,9 @@ void __init kasan_early_init(void)
for (i = 0; i < PTRS_PER_PUD; i++)
kasan_zero_pud[i] = __pud(pud_val);
 
+   for (i = 0; CONFIG_PGTABLE_LEVELS >= 5 && i < PTRS_PER_P4D; i++)
+   kasan_zero_p4d[i] = __p4d(p4d_val);
+
kasan_map_early_shadow(early_level4_pgt);
kasan_map_early_shadow(init_level4_pgt);
 }

[tip:x86/mm] x86/kasan: Extend KASAN to support 5-level paging

[tip-bot for Kirill A. Shutemov]

Commit-ID:  5480bb61cfba5de23df59793527c3a37c0d2e247
Gitweb: http://git.kernel.org/tip/5480bb61cfba5de23df59793527c3a37c0d2e247
Author: Kirill A. Shutemov 
AuthorDate: Thu, 30 Mar 2017 11:07:30 +0300
Committer:  Ingo Molnar 
CommitDate: Tue, 4 Apr 2017 08:22:34 +0200

x86/kasan: Extend KASAN to support 5-level paging

This patch bring support for a non-folded additional page table level.

Signed-off-by: Kirill A. Shutemov 
Cc: Andrew Morton 
Cc: Andrey Ryabinin 
Cc: Andy Lutomirski 
Cc: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Brian Gerst 
Cc: Dave Hansen 
Cc: Denys Vlasenko 
Cc: Dmitry Vyukov 
Cc: H. Peter Anvin 
Cc: Josh Poimboeuf 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-a...@vger.kernel.org
Cc: linux...@kvack.org
Link: 
http://lkml.kernel.org/r/20170330080731.65421-7-kirill.shute...@linux.intel.com
Signed-off-by: Ingo Molnar 
---
 arch/x86/mm/kasan_init_64.c | 18 --
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/arch/x86/mm/kasan_init_64.c b/arch/x86/mm/kasan_init_64.c
index 3d1059d..47efdcf 100644
--- a/arch/x86/mm/kasan_init_64.c
+++ b/arch/x86/mm/kasan_init_64.c
@@ -55,8 +55,18 @@ static void __init kasan_map_early_shadow(pgd_t *pgd)
unsigned long end = KASAN_SHADOW_END;
 
for (i = pgd_index(start); start < end; i++) {
-   pgd[i] = __pgd(__pa_nodebug(kasan_zero_pud)
-   | _KERNPG_TABLE);
+   switch (CONFIG_PGTABLE_LEVELS) {
+   case 4:
+   pgd[i] = __pgd(__pa_nodebug(kasan_zero_pud) |
+   _KERNPG_TABLE);
+   break;
+   case 5:
+   pgd[i] = __pgd(__pa_nodebug(kasan_zero_p4d) |
+   _KERNPG_TABLE);
+   break;
+   default:
+   BUILD_BUG();
+   }
start += PGDIR_SIZE;
}
 }
@@ -84,6 +94,7 @@ void __init kasan_early_init(void)
pteval_t pte_val = __pa_nodebug(kasan_zero_page) | __PAGE_KERNEL;
pmdval_t pmd_val = __pa_nodebug(kasan_zero_pte) | _KERNPG_TABLE;
pudval_t pud_val = __pa_nodebug(kasan_zero_pmd) | _KERNPG_TABLE;
+   p4dval_t p4d_val = __pa_nodebug(kasan_zero_pud) | _KERNPG_TABLE;
 
for (i = 0; i < PTRS_PER_PTE; i++)
kasan_zero_pte[i] = __pte(pte_val);
@@ -94,6 +105,9 @@ void __init kasan_early_init(void)
for (i = 0; i < PTRS_PER_PUD; i++)
kasan_zero_pud[i] = __pud(pud_val);
 
+   for (i = 0; CONFIG_PGTABLE_LEVELS >= 5 && i < PTRS_PER_P4D; i++)
+   kasan_zero_p4d[i] = __p4d(p4d_val);
+
kasan_map_early_shadow(early_level4_pgt);
kasan_map_early_shadow(init_level4_pgt);
 }