Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching

Pull livepatching updates from Jiri Kosina:
 "These are mostly smaller things that got accumulated during the
  development cycle.  The unified solution is still being worked on and
  is not mature enough for 4.1 yet.

   - s390 livepatching support, from Jiri Slaby (has Ack from s390
     maintainers)

   - error handling simplification, from Josh Poimboeuf

   - two minor code cleanups from Josh Poimboeuf and Miroslav Benes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: add support on s390
  livepatch: remove unnecessary call to klp_find_object_module()
  livepatch: simplify disable error path
  livepatch: remove extern specifier from header files
This commit is contained in:
Linus Torvalds 2015-04-14 10:15:34 -07:00
commit 9497d7380b
5 changed files with 69 additions and 58 deletions

View File

@ -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
@ -159,6 +160,8 @@ source "init/Kconfig"
source "kernel/Kconfig.freezer"
source "kernel/livepatch/Kconfig"
menu "Processor type and features"
config HAVE_MARCH_Z900_FEATURES

View File

@ -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

View File

@ -32,8 +32,8 @@ static inline int klp_check_compiler_support(void)
#endif
return 0;
}
extern int klp_write_module_reloc(struct module *mod, unsigned long type,
unsigned long loc, unsigned long value);
int klp_write_module_reloc(struct module *mod, unsigned long type,
unsigned long loc, unsigned long value);
static inline void klp_arch_set_pc(struct pt_regs *regs, unsigned long ip)
{

View File

@ -123,10 +123,10 @@ struct klp_patch {
enum klp_state state;
};
extern int klp_register_patch(struct klp_patch *);
extern int klp_unregister_patch(struct klp_patch *);
extern int klp_enable_patch(struct klp_patch *);
extern int klp_disable_patch(struct klp_patch *);
int klp_register_patch(struct klp_patch *);
int klp_unregister_patch(struct klp_patch *);
int klp_enable_patch(struct klp_patch *);
int klp_disable_patch(struct klp_patch *);
#endif /* CONFIG_LIVEPATCH */

View File

@ -335,32 +335,20 @@ static void notrace klp_ftrace_handler(unsigned long ip,
rcu_read_unlock();
}
static int klp_disable_func(struct klp_func *func)
static void klp_disable_func(struct klp_func *func)
{
struct klp_ops *ops;
int ret;
if (WARN_ON(func->state != KLP_ENABLED))
return -EINVAL;
if (WARN_ON(!func->old_addr))
return -EINVAL;
WARN_ON(func->state != KLP_ENABLED);
WARN_ON(!func->old_addr);
ops = klp_find_ops(func->old_addr);
if (WARN_ON(!ops))
return -EINVAL;
return;
if (list_is_singular(&ops->func_stack)) {
ret = unregister_ftrace_function(&ops->fops);
if (ret) {
pr_err("failed to unregister ftrace handler for function '%s' (%d)\n",
func->old_name, ret);
return ret;
}
ret = ftrace_set_filter_ip(&ops->fops, func->old_addr, 1, 0);
if (ret)
pr_warn("function unregister succeeded but failed to clear the filter\n");
WARN_ON(unregister_ftrace_function(&ops->fops));
WARN_ON(ftrace_set_filter_ip(&ops->fops, func->old_addr, 1, 0));
list_del_rcu(&func->stack_node);
list_del(&ops->node);
@ -370,8 +358,6 @@ static int klp_disable_func(struct klp_func *func)
}
func->state = KLP_DISABLED;
return 0;
}
static int klp_enable_func(struct klp_func *func)
@ -432,23 +418,15 @@ static int klp_enable_func(struct klp_func *func)
return ret;
}
static int klp_disable_object(struct klp_object *obj)
static void klp_disable_object(struct klp_object *obj)
{
struct klp_func *func;
int ret;
for (func = obj->funcs; func->old_name; func++) {
if (func->state != KLP_ENABLED)
continue;
ret = klp_disable_func(func);
if (ret)
return ret;
}
for (func = obj->funcs; func->old_name; func++)
if (func->state == KLP_ENABLED)
klp_disable_func(func);
obj->state = KLP_DISABLED;
return 0;
}
static int klp_enable_object(struct klp_object *obj)
@ -464,22 +442,19 @@ static int klp_enable_object(struct klp_object *obj)
for (func = obj->funcs; func->old_name; func++) {
ret = klp_enable_func(func);
if (ret)
goto unregister;
if (ret) {
klp_disable_object(obj);
return ret;
}
}
obj->state = KLP_ENABLED;
return 0;
unregister:
WARN_ON(klp_disable_object(obj));
return ret;
}
static int __klp_disable_patch(struct klp_patch *patch)
{
struct klp_object *obj;
int ret;
/* enforce stacking: only the last enabled patch can be disabled */
if (!list_is_last(&patch->list, &klp_patches) &&
@ -489,12 +464,8 @@ static int __klp_disable_patch(struct klp_patch *patch)
pr_notice("disabling patch '%s'\n", patch->mod->name);
for (obj = patch->objs; obj->funcs; obj++) {
if (obj->state != KLP_ENABLED)
continue;
ret = klp_disable_object(obj);
if (ret)
return ret;
if (obj->state == KLP_ENABLED)
klp_disable_object(obj);
}
patch->state = KLP_DISABLED;
@ -553,8 +524,6 @@ static int __klp_enable_patch(struct klp_patch *patch)
pr_notice("enabling patch '%s'\n", patch->mod->name);
for (obj = patch->objs; obj->funcs; obj++) {
klp_find_object_module(obj);
if (!klp_is_object_loaded(obj))
continue;
@ -945,7 +914,6 @@ static void klp_module_notify_going(struct klp_patch *patch,
{
struct module *pmod = patch->mod;
struct module *mod = obj->mod;
int ret;
if (patch->state == KLP_DISABLED)
goto disabled;
@ -953,10 +921,7 @@ static void klp_module_notify_going(struct klp_patch *patch,
pr_notice("reverting patch '%s' on unloading module '%s'\n",
pmod->name, mod->name);
ret = klp_disable_object(obj);
if (ret)
pr_warn("failed to revert patch '%s' on module '%s' (%d)\n",
pmod->name, mod->name, ret);
klp_disable_object(obj);
disabled:
klp_free_object_loaded(obj);