Livepatch backporting from Openeuler-kernel

arch/arm/Kconfig

@@ -123,6 +123,7 @@ config ARM
 	select RTC_LIB
 	select SET_FS
 	select SYS_SUPPORTS_APM_EMULATION
+	select HAVE_LIVEPATCH_WO_FTRACE
 	# Above selects are sorted alphabetically; please add new ones
 	# according to that.  Thanks.
 	help
@@ -2050,3 +2051,5 @@ source "arch/arm/crypto/Kconfig"
 endif
 
 source "arch/arm/Kconfig.assembler"
+
+source "kernel/livepatch/Kconfig"

arch/arm/include/asm/livepatch.h

@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * livepatch.h - arm-specific Kernel Live Patching Core
+ *
+ * Copyright (C) 2018  Huawei Technologies Co., Ltd.
+ *
+ * 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/>.
+ */
+
+#ifndef _ASM_ARM_LIVEPATCH_H
+#define _ASM_ARM_LIVEPATCH_H
+
+#include <linux/module.h>
+
+struct klp_patch;
+struct klp_func;
+
+/* kernel livepatch instruction barrier */
+#define klp_smp_isb()  isb()
+
+int arch_klp_patch_func(struct klp_func *func);
+void arch_klp_unpatch_func(struct klp_func *func);
+
+#ifdef CONFIG_LIVEPATCH_STOP_MACHINE_CONSISTENCY
+int klp_check_calltrace(struct klp_patch *patch, int enable);
+#endif
+
+#endif /* _ASM_ARM_LIVEPATCH_H */

arch/arm/include/asm/module.h

@@ -20,7 +20,7 @@ enum {
 #endif
 
 struct mod_plt_sec {
-	struct elf32_shdr	*plt;
+	int			plt_shndx;
 	int			plt_count;
 };
 
@@ -35,7 +35,8 @@ struct mod_arch_specific {
 };
 
 struct module;
-u32 get_module_plt(struct module *mod, unsigned long loc, Elf32_Addr val);
+u32 get_module_plt(struct module *mod, Elf32_Shdr *sechdrs,
+		   unsigned long loc, Elf32_Addr val);
 
 #ifdef CONFIG_THUMB2_KERNEL
 #define HAVE_ARCH_KALLSYMS_SYMBOL_VALUE

arch/arm/include/asm/thread_info.h

@@ -135,6 +135,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
 #define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
 #define TIF_SYSCALL_TRACEPOINT	6	/* syscall tracepoint instrumentation */
 #define TIF_SECCOMP		7	/* seccomp syscall filtering active */
+#define TIF_PATCH_PENDING	8	/* pending live patching update */
 
 #define TIF_USING_IWMMXT	17
 #define TIF_MEMDIE		18	/* is terminating due to OOM killer */
@@ -149,6 +150,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp *,
 #define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
 #define _TIF_SECCOMP		(1 << TIF_SECCOMP)
 #define _TIF_USING_IWMMXT	(1 << TIF_USING_IWMMXT)
+#define _TIF_PATCH_PENDING	(1 << TIF_PATCH_PENDING)
 
 /* Checks for any syscall work in entry-common.S */
 #define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \

arch/arm/kernel/Makefile

@@ -55,6 +55,7 @@ obj-$(CONFIG_ARM_ARCH_TIMER)	+= arch_timer.o
 obj-$(CONFIG_FUNCTION_TRACER)	+= entry-ftrace.o
 obj-$(CONFIG_DYNAMIC_FTRACE)	+= ftrace.o insn.o patch.o
 obj-$(CONFIG_FUNCTION_GRAPH_TRACER)	+= ftrace.o insn.o patch.o
+obj-$(CONFIG_LIVEPATCH)	+= livepatch.o insn.o patch.o
 obj-$(CONFIG_JUMP_LABEL)	+= jump_label.o insn.o patch.o
 obj-$(CONFIG_KEXEC)		+= machine_kexec.o relocate_kernel.o
 # Main staffs in KPROBES are in arch/arm/probes/ .