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Message-Id: <1236265498.31324.12.camel@penberg-laptop>
Date: Thu, 05 Mar 2009 17:04:58 +0200
From: Pekka Enberg <penberg@...helsinki.fi>
To: mingo@...e.hu
Cc: x86@...nel.org, linux-kernel@...r.kernel.org
Subject: [PATCH 2/2] x86: unify noexec handling
From: Pekka Enberg <penberg@...helsinki.fi>
Impact: cleanup
This patch unifies noexec handling on 32-bit and 64-bit.
Signed-off-by: Pekka Enberg <penberg@...helsinki.fi>
---
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 a830a06..f7719b1 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)
{
@@ -156,13 +217,11 @@ 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 5e5126e..3464b1f 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -573,56 +573,6 @@ 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 bb50ce8..4bd5b17 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;
/*
--
1.5.4.3
--
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