livepatch: add support on s390

This is a trivial port from kGraft. Module relocations are not supported yet.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 68b68d755fdfe46c0a9aecad0cebef4e1e079487..eba9c1d0dab56e2dc6027aaefb2d097c71911d06 100644 (file)
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -133,6 +133,7 @@ config S390
        select HAVE_KPROBES
        select HAVE_KRETPROBES
        select HAVE_KVM if 64BIT
+       select HAVE_LIVEPATCH
        select HAVE_MEMBLOCK
        select HAVE_MEMBLOCK_NODE_MAP
        select HAVE_MEMBLOCK_PHYS_MAP
@@ -160,6 +161,8 @@ source "init/Kconfig"
 
 source "kernel/Kconfig.freezer"
 
+source "kernel/livepatch/Kconfig"
+
 menu "Processor type and features"
 
 config HAVE_MARCH_Z900_FEATURES

diff --git a/arch/s390/include/asm/livepatch.h b/arch/s390/include/asm/livepatch.h
new file mode 100644 (file)
index 0000000..7aa7991
--- /dev/null
+++ b/arch/s390/include/asm/livepatch.h
@@ -0,0 +1,43 @@
+/*
+ * livepatch.h - s390-specific Kernel Live Patching Core
+ *
+ *  Copyright (c) 2013-2015 SUSE
+ *   Authors: Jiri Kosina
+ *           Vojtech Pavlik
+ *           Jiri Slaby
+ */
+
+/*
+ * 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.
+ */
+
+#ifndef ASM_LIVEPATCH_H
+#define ASM_LIVEPATCH_H
+
+#include <linux/module.h>
+
+#ifdef CONFIG_LIVEPATCH
+static inline int klp_check_compiler_support(void)
+{
+       return 0;
+}
+
+static inline int klp_write_module_reloc(struct module *mod, unsigned long
+               type, unsigned long loc, unsigned long value)
+{
+       /* not supported yet */
+       return -ENOSYS;
+}
+
+static inline void klp_arch_set_pc(struct pt_regs *regs, unsigned long ip)
+{
+       regs->psw.addr = ip;
+}
+#else
+#error Live patching support is disabled; check CONFIG_LIVEPATCH
+#endif
+
+#endif