1 files changed, 65 insertions, 0 deletions
diff --git a/arch/x86/kernel/livepatch.c b/arch/x86/kernel/livepatch.c
new file mode 100644
index 000000000..e9d252d87
--- /dev/null
+++ b/arch/x86/kernel/livepatch.c
@@ -0,0 +1,65 @@
+/*
+ * livepatch.c - x86-specific Kernel Live Patching Core
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/livepatch.h>
+#include <asm/text-patching.h>
+
+/* Apply per-object alternatives. Based on x86 module_finalize() */
+void arch_klp_init_object_loaded(struct klp_patch *patch,
+				 struct klp_object *obj)
+{
+	int cnt;
+	struct klp_modinfo *info;
+	Elf_Shdr *s, *alt = NULL, *para = NULL;
+	void *aseg, *pseg;
+	const char *objname;
+	char sec_objname[MODULE_NAME_LEN];
+	char secname[KSYM_NAME_LEN];
+
+	info = patch->mod->klp_info;
+	objname = obj->name ? obj->name : "vmlinux";
+
+	/* See livepatch core code for BUILD_BUG_ON() explanation */
+	BUILD_BUG_ON(MODULE_NAME_LEN < 56 || KSYM_NAME_LEN != 128);
+
+	for (s = info->sechdrs; s < info->sechdrs + info->hdr.e_shnum; s++) {
+		/* Apply per-object .klp.arch sections */
+		cnt = sscanf(info->secstrings + s->sh_name,
+			     ".klp.arch.%55[^.].%127s",
+			     sec_objname, secname);
+		if (cnt != 2)
+			continue;
+		if (strcmp(sec_objname, objname))
+			continue;
+		if (!strcmp(".altinstructions", secname))
+			alt = s;
+		if (!strcmp(".parainstructions", secname))
+			para = s;
+	}
+
+	if (alt) {
+		aseg = (void *) alt->sh_addr;
+		apply_alternatives(aseg, aseg + alt->sh_size);
+	}
+
+	if (para) {
+		pseg = (void *) para->sh_addr;
+		apply_paravirt(pseg, pseg + para->sh_size);
+	}
+}