lkml.org 
[lkml]   [2009]   [Mar]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[tip:x86/mm] x86: unify noexec handling
Commit-ID:  ffc442a919c8b714383e7464e905485bafc22039
Gitweb: http://git.kernel.org/tip/ffc442a919c8b714383e7464e905485bafc22039
Author: "Pekka Enberg" <penberg@cs.helsinki.fi>
AuthorDate: Thu, 5 Mar 2009 17:04:58 +0200
Commit: Ingo Molnar <mingo@elte.hu>
CommitDate: Fri, 6 Mar 2009 15:25:53 +0100

x86: unify noexec handling

Impact: cleanup

This patch unifies noexec handling on 32-bit and 64-bit.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
LKML-Reference: <1236265498.31324.12.camel@penberg-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>


---
arch/x86/include/asm/pgtable_types.h | 1 -
arch/x86/mm/init.c | 65 ++++++++++++++++++++++++++++++++--
arch/x86/mm/init_32.c | 50 --------------------------
arch/x86/mm/init_64.c | 33 -----------------
4 files changed, 62 insertions(+), 87 deletions(-)
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index b8238dc..4d258ad 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -273,7 +273,6 @@ typedef struct page *pgtable_t;

extern pteval_t __supported_pte_mask;
extern int nx_enabled;
-extern void set_nx(void);

#define pgprot_writecombine pgprot_writecombine
extern pgprot_t pgprot_writecombine(pgprot_t prot);
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 15219e0..5d06d25 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -22,6 +22,67 @@ int direct_gbpages
#endif
;

+#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
+static int disable_nx __initdata;
+
+/*
+ * noexec = on|off
+ *
+ * Control non-executable mappings for processes.
+ *
+ * on Enable
+ * off Disable
+ */
+static int __init noexec_setup(char *str)
+{
+ if (!str)
+ return -EINVAL;
+ if (!strncmp(str, "on", 2)) {
+ __supported_pte_mask |= _PAGE_NX;
+ disable_nx = 0;
+ } else if (!strncmp(str, "off", 3)) {
+ disable_nx = 1;
+ __supported_pte_mask &= ~_PAGE_NX;
+ }
+ return 0;
+}
+early_param("noexec", noexec_setup);
+#endif
+
+#ifdef CONFIG_X86_PAE
+static void __init set_nx(void)
+{
+ unsigned int v[4], l, h;
+
+ if (cpu_has_pae && (cpuid_eax(0x80000000) > 0x80000001)) {
+ cpuid(0x80000001, &v[0], &v[1], &v[2], &v[3]);
+
+ if ((v[3] & (1 << 20)) && !disable_nx) {
+ rdmsr(MSR_EFER, l, h);
+ l |= EFER_NX;
+ wrmsr(MSR_EFER, l, h);
+ nx_enabled = 1;
+ __supported_pte_mask |= _PAGE_NX;
+ }
+ }
+}
+#else
+static inline void set_nx(void)
+{
+}
+#endif
+
+#ifdef CONFIG_X86_64
+void __cpuinit check_efer(void)
+{
+ unsigned long efer;
+
+ rdmsrl(MSR_EFER, efer);
+ if (!(efer & EFER_NX) || disable_nx)
+ __supported_pte_mask &= ~_PAGE_NX;
+}
+#endif
+
static void __init find_early_table_space(unsigned long end, int use_pse,
int use_gbpages)
{
@@ -158,13 +219,11 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
use_gbpages = direct_gbpages;
#endif

-#ifdef CONFIG_X86_32
-#ifdef CONFIG_X86_PAE
set_nx();
if (nx_enabled)
printk(KERN_INFO "NX (Execute Disable) protection: active\n");
-#endif

+#ifdef CONFIG_X86_32
/* Enable PSE if available */
if (cpu_has_pse)
set_in_cr4(X86_CR4_PSE);
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 2966c6b..8ff1173 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -592,56 +592,6 @@ int nx_enabled;
pteval_t __supported_pte_mask __read_mostly = ~(_PAGE_NX | _PAGE_GLOBAL | _PAGE_IOMAP);
EXPORT_SYMBOL_GPL(__supported_pte_mask);

-#ifdef CONFIG_X86_PAE
-
-static int disable_nx __initdata;
-
-/*
- * noexec = on|off
- *
- * Control non executable mappings.
- *
- * on Enable
- * off Disable
- */
-static int __init noexec_setup(char *str)
-{
- if (!str || !strcmp(str, "on")) {
- if (cpu_has_nx) {
- __supported_pte_mask |= _PAGE_NX;
- disable_nx = 0;
- }
- } else {
- if (!strcmp(str, "off")) {
- disable_nx = 1;
- __supported_pte_mask &= ~_PAGE_NX;
- } else {
- return -EINVAL;
- }
- }
-
- return 0;
-}
-early_param("noexec", noexec_setup);
-
-void __init set_nx(void)
-{
- unsigned int v[4], l, h;
-
- if (cpu_has_pae && (cpuid_eax(0x80000000) > 0x80000001)) {
- cpuid(0x80000001, &v[0], &v[1], &v[2], &v[3]);
-
- if ((v[3] & (1 << 20)) && !disable_nx) {
- rdmsr(MSR_EFER, l, h);
- l |= EFER_NX;
- wrmsr(MSR_EFER, l, h);
- nx_enabled = 1;
- __supported_pte_mask |= _PAGE_NX;
- }
- }
-}
-#endif
-
/* user-defined highmem size */
static unsigned int highmem_pages = -1;

diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 54efa57..3073d10 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -85,39 +85,6 @@ early_param("gbpages", parse_direct_gbpages_on);
pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP;
EXPORT_SYMBOL_GPL(__supported_pte_mask);

-static int disable_nx __cpuinitdata;
-
-/*
- * noexec=on|off
- * Control non-executable mappings for 64-bit processes.
- *
- * on Enable (default)
- * off Disable
- */
-static int __init nonx_setup(char *str)
-{
- if (!str)
- return -EINVAL;
- if (!strncmp(str, "on", 2)) {
- __supported_pte_mask |= _PAGE_NX;
- disable_nx = 0;
- } else if (!strncmp(str, "off", 3)) {
- disable_nx = 1;
- __supported_pte_mask &= ~_PAGE_NX;
- }
- return 0;
-}
-early_param("noexec", nonx_setup);
-
-void __cpuinit check_efer(void)
-{
- unsigned long efer;
-
- rdmsrl(MSR_EFER, efer);
- if (!(efer & EFER_NX) || disable_nx)
- __supported_pte_mask &= ~_PAGE_NX;
-}
-
int force_personality32;

/*

\
 
 \ /
  Last update: 2009-03-06 15:51    [from the cache]
©2003-2011 Jasper Spaans