Merge branch 'x86/unify-cpu-detect' into x86-v28-for-linus-phase4-D

[linux-2.6-omap-h63xx.git] / arch / x86 / mm / init_64.c

diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index fb30486c82f7f7c21e036feebb9cb58f957d8a36..83e13f2d53d2a94d95f3e4657eb570ea784c4a72 100644 (file)
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -88,6 +88,62 @@ early_param("gbpages", parse_direct_gbpages_on);
 
 int after_bootmem;
 
+unsigned long __supported_pte_mask __read_mostly = ~0UL;
+EXPORT_SYMBOL_GPL(__supported_pte_mask);
+
+static int do_not_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;
+               do_not_nx = 0;
+       } else if (!strncmp(str, "off", 3)) {
+               do_not_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) || do_not_nx)
+               __supported_pte_mask &= ~_PAGE_NX;
+}
+
+int force_personality32;
+
+/*
+ * noexec32=on|off
+ * Control non executable heap for 32bit processes.
+ * To control the stack too use noexec=off
+ *
+ * on  PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
+ * off PROT_READ implies PROT_EXEC
+ */
+static int __init nonx32_setup(char *str)
+{
+       if (!strcmp(str, "on"))
+               force_personality32 &= ~READ_IMPLIES_EXEC;
+       else if (!strcmp(str, "off"))
+               force_personality32 |= READ_IMPLIES_EXEC;
+       return 1;
+}
+__setup("noexec32=", nonx32_setup);
+
 /*
  * NOTE: This function is marked __ref because it calls __init function
  * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.