[tip:x86/pti] x86/mm/pti: Make pti_clone_kernel_text() compile on 32 bit
Commit-ID: 39d668e04edad25abe184fb329ce35a131146ee5
Gitweb: https://git.kernel.org/tip/39d668e04edad25abe184fb329ce35a131146ee5
Author: Joerg Roedel
AuthorDate: Wed, 18 Jul 2018 11:41:04 +0200
Committer: Thomas Gleixner
CommitDate: Fri, 20 Jul 2018 01:11:44 +0200
x86/mm/pti: Make pti_clone_kernel_text() compile on 32 bit
The pti_clone_kernel_text() function references __end_rodata_hpage_align,
which is only present on x86-64. This makes sense as the end of the rodata
section is not huge-page aligned on 32 bit.
Nevertheless a symbol is required for the function that points at the right
address for both 32 and 64 bit. Introduce __end_rodata_aligned for that
purpose and use it in pti_clone_kernel_text().
Signed-off-by: Joerg Roedel
Signed-off-by: Thomas Gleixner
Tested-by: Pavel Machek
Cc: "H . Peter Anvin"
Cc: linux...@kvack.org
Cc: Linus Torvalds
Cc: Andy Lutomirski
Cc: Dave Hansen
Cc: Josh Poimboeuf
Cc: Juergen Gross
Cc: Peter Zijlstra
Cc: Borislav Petkov
Cc: Jiri Kosina
Cc: Boris Ostrovsky
Cc: Brian Gerst
Cc: David Laight
Cc: Denys Vlasenko
Cc: Eduardo Valentin
Cc: Greg KH
Cc: Will Deacon
Cc: aligu...@amazon.com
Cc: daniel.gr...@iaik.tugraz.at
Cc: hu...@google.com
Cc: keesc...@google.com
Cc: Andrea Arcangeli
Cc: Waiman Long
Cc: "David H . Gutteridge"
Cc: j...@8bytes.org
Link:
https://lkml.kernel.org/r/1531906876-13451-28-git-send-email-j...@8bytes.org
---
arch/x86/include/asm/sections.h | 1 +
arch/x86/kernel/vmlinux.lds.S | 17 ++---
arch/x86/mm/pti.c | 2 +-
3 files changed, 12 insertions(+), 8 deletions(-)
diff --git a/arch/x86/include/asm/sections.h b/arch/x86/include/asm/sections.h
index 5c019d23d06b..4a911a382ade 100644
--- a/arch/x86/include/asm/sections.h
+++ b/arch/x86/include/asm/sections.h
@@ -7,6 +7,7 @@
extern char __brk_base[], __brk_limit[];
extern struct exception_table_entry __stop___ex_table[];
+extern char __end_rodata_aligned[];
#if defined(CONFIG_X86_64)
extern char __end_rodata_hpage_align[];
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 5e1458f609a1..8bde0a419f86 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -55,19 +55,22 @@ jiffies_64 = jiffies;
* so we can enable protection checks as well as retain 2MB large page
* mappings for kernel text.
*/
-#define X64_ALIGN_RODATA_BEGIN . = ALIGN(HPAGE_SIZE);
+#define X86_ALIGN_RODATA_BEGIN . = ALIGN(HPAGE_SIZE);
-#define X64_ALIGN_RODATA_END \
+#define X86_ALIGN_RODATA_END \
. = ALIGN(HPAGE_SIZE); \
- __end_rodata_hpage_align = .;
+ __end_rodata_hpage_align = .; \
+ __end_rodata_aligned = .;
#define ALIGN_ENTRY_TEXT_BEGIN . = ALIGN(PMD_SIZE);
#define ALIGN_ENTRY_TEXT_END . = ALIGN(PMD_SIZE);
#else
-#define X64_ALIGN_RODATA_BEGIN
-#define X64_ALIGN_RODATA_END
+#define X86_ALIGN_RODATA_BEGIN
+#define X86_ALIGN_RODATA_END \
+ . = ALIGN(PAGE_SIZE); \
+ __end_rodata_aligned = .;
#define ALIGN_ENTRY_TEXT_BEGIN
#define ALIGN_ENTRY_TEXT_END
@@ -141,9 +144,9 @@ SECTIONS
/* .text should occupy whole number of pages */
. = ALIGN(PAGE_SIZE);
- X64_ALIGN_RODATA_BEGIN
+ X86_ALIGN_RODATA_BEGIN
RO_DATA(PAGE_SIZE)
- X64_ALIGN_RODATA_END
+ X86_ALIGN_RODATA_END
/* Data */
.data : AT(ADDR(.data) - LOAD_OFFSET) {
diff --git a/arch/x86/mm/pti.c b/arch/x86/mm/pti.c
index a594e3b6401a..453d23760941 100644
--- a/arch/x86/mm/pti.c
+++ b/arch/x86/mm/pti.c
@@ -470,7 +470,7 @@ void pti_clone_kernel_text(void)
* clone the areas past rodata, they might contain secrets.
*/
unsigned long start = PFN_ALIGN(_text);
- unsigned long end = (unsigned long)__end_rodata_hpage_align;
+ unsigned long end = (unsigned long)__end_rodata_aligned;
if (!pti_kernel_image_global_ok())
return;
[tip:x86/pti] x86/mm/pti: Make pti_clone_kernel_text() compile on 32 bit
Commit-ID: 39d668e04edad25abe184fb329ce35a131146ee5
Gitweb: https://git.kernel.org/tip/39d668e04edad25abe184fb329ce35a131146ee5
Author: Joerg Roedel
AuthorDate: Wed, 18 Jul 2018 11:41:04 +0200
Committer: Thomas Gleixner
CommitDate: Fri, 20 Jul 2018 01:11:44 +0200
x86/mm/pti: Make pti_clone_kernel_text() compile on 32 bit
The pti_clone_kernel_text() function references __end_rodata_hpage_align,
which is only present on x86-64. This makes sense as the end of the rodata
section is not huge-page aligned on 32 bit.
Nevertheless a symbol is required for the function that points at the right
address for both 32 and 64 bit. Introduce __end_rodata_aligned for that
purpose and use it in pti_clone_kernel_text().
Signed-off-by: Joerg Roedel
Signed-off-by: Thomas Gleixner
Tested-by: Pavel Machek
Cc: "H . Peter Anvin"
Cc: linux...@kvack.org
Cc: Linus Torvalds
Cc: Andy Lutomirski
Cc: Dave Hansen
Cc: Josh Poimboeuf
Cc: Juergen Gross
Cc: Peter Zijlstra
Cc: Borislav Petkov
Cc: Jiri Kosina
Cc: Boris Ostrovsky
Cc: Brian Gerst
Cc: David Laight
Cc: Denys Vlasenko
Cc: Eduardo Valentin
Cc: Greg KH
Cc: Will Deacon
Cc: aligu...@amazon.com
Cc: daniel.gr...@iaik.tugraz.at
Cc: hu...@google.com
Cc: keesc...@google.com
Cc: Andrea Arcangeli
Cc: Waiman Long
Cc: "David H . Gutteridge"
Cc: j...@8bytes.org
Link:
https://lkml.kernel.org/r/1531906876-13451-28-git-send-email-j...@8bytes.org
---
arch/x86/include/asm/sections.h | 1 +
arch/x86/kernel/vmlinux.lds.S | 17 ++---
arch/x86/mm/pti.c | 2 +-
3 files changed, 12 insertions(+), 8 deletions(-)
diff --git a/arch/x86/include/asm/sections.h b/arch/x86/include/asm/sections.h
index 5c019d23d06b..4a911a382ade 100644
--- a/arch/x86/include/asm/sections.h
+++ b/arch/x86/include/asm/sections.h
@@ -7,6 +7,7 @@
extern char __brk_base[], __brk_limit[];
extern struct exception_table_entry __stop___ex_table[];
+extern char __end_rodata_aligned[];
#if defined(CONFIG_X86_64)
extern char __end_rodata_hpage_align[];
diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index 5e1458f609a1..8bde0a419f86 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -55,19 +55,22 @@ jiffies_64 = jiffies;
* so we can enable protection checks as well as retain 2MB large page
* mappings for kernel text.
*/
-#define X64_ALIGN_RODATA_BEGIN . = ALIGN(HPAGE_SIZE);
+#define X86_ALIGN_RODATA_BEGIN . = ALIGN(HPAGE_SIZE);
-#define X64_ALIGN_RODATA_END \
+#define X86_ALIGN_RODATA_END \
. = ALIGN(HPAGE_SIZE); \
- __end_rodata_hpage_align = .;
+ __end_rodata_hpage_align = .; \
+ __end_rodata_aligned = .;
#define ALIGN_ENTRY_TEXT_BEGIN . = ALIGN(PMD_SIZE);
#define ALIGN_ENTRY_TEXT_END . = ALIGN(PMD_SIZE);
#else
-#define X64_ALIGN_RODATA_BEGIN
-#define X64_ALIGN_RODATA_END
+#define X86_ALIGN_RODATA_BEGIN
+#define X86_ALIGN_RODATA_END \
+ . = ALIGN(PAGE_SIZE); \
+ __end_rodata_aligned = .;
#define ALIGN_ENTRY_TEXT_BEGIN
#define ALIGN_ENTRY_TEXT_END
@@ -141,9 +144,9 @@ SECTIONS
/* .text should occupy whole number of pages */
. = ALIGN(PAGE_SIZE);
- X64_ALIGN_RODATA_BEGIN
+ X86_ALIGN_RODATA_BEGIN
RO_DATA(PAGE_SIZE)
- X64_ALIGN_RODATA_END
+ X86_ALIGN_RODATA_END
/* Data */
.data : AT(ADDR(.data) - LOAD_OFFSET) {
diff --git a/arch/x86/mm/pti.c b/arch/x86/mm/pti.c
index a594e3b6401a..453d23760941 100644
--- a/arch/x86/mm/pti.c
+++ b/arch/x86/mm/pti.c
@@ -470,7 +470,7 @@ void pti_clone_kernel_text(void)
* clone the areas past rodata, they might contain secrets.
*/
unsigned long start = PFN_ALIGN(_text);
- unsigned long end = (unsigned long)__end_rodata_hpage_align;
+ unsigned long end = (unsigned long)__end_rodata_aligned;
if (!pti_kernel_image_global_ok())
return;
