summaryrefslogtreecommitdiffstats
path: root/kernel/arch/x86/mm/setup_nx.c
diff options
context:
space:
mode:
authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/x86/mm/setup_nx.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/x86/mm/setup_nx.c')
-rw-r--r--kernel/arch/x86/mm/setup_nx.c60
1 files changed, 60 insertions, 0 deletions
diff --git a/kernel/arch/x86/mm/setup_nx.c b/kernel/arch/x86/mm/setup_nx.c
new file mode 100644
index 000000000..90555bf60
--- /dev/null
+++ b/kernel/arch/x86/mm/setup_nx.c
@@ -0,0 +1,60 @@
+#include <linux/spinlock.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+
+#include <asm/pgtable.h>
+#include <asm/proto.h>
+
+static int disable_nx;
+
+/*
+ * 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)) {
+ disable_nx = 0;
+ } else if (!strncmp(str, "off", 3)) {
+ disable_nx = 1;
+ }
+ x86_configure_nx();
+ return 0;
+}
+early_param("noexec", noexec_setup);
+
+void x86_configure_nx(void)
+{
+ if (cpu_has_nx && !disable_nx)
+ __supported_pte_mask |= _PAGE_NX;
+ else
+ __supported_pte_mask &= ~_PAGE_NX;
+}
+
+void __init x86_report_nx(void)
+{
+ if (!cpu_has_nx) {
+ printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
+ "missing in CPU!\n");
+ } else {
+#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
+ if (disable_nx) {
+ printk(KERN_INFO "NX (Execute Disable) protection: "
+ "disabled by kernel command line option\n");
+ } else {
+ printk(KERN_INFO "NX (Execute Disable) protection: "
+ "active\n");
+ }
+#else
+ /* 32bit non-PAE kernel, NX cannot be used */
+ printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
+ "cannot be enabled: non-PAE kernel!\n");
+#endif
+ }
+}