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/*
* Copyright (c) 2016 Oracle and/or its affiliates. All rights reserved.
*
*/
#include "config.h"
#include <xen/lib.h>
#include <xen/types.h>
#include <xen/version.h>
#include <xen/livepatch.h>
#include <xen/livepatch_payload.h>
#include <public/sysctl.h>
static const char hello_world_patch_this_fnc[] = "xen_extra_version";
extern const char *xen_hello_world(void);
static unsigned int cnt;
static void apply_hook(void)
{
printk(KERN_DEBUG "Hook executing.\n");
}
static void revert_hook(void)
{
printk(KERN_DEBUG "Hook unloaded.\n");
}
static void hi_func(void)
{
printk(KERN_DEBUG "%s: Hi! (called %u times)\n", __func__, ++cnt);
};
static void check_fnc(void)
{
printk(KERN_DEBUG "%s: Hi func called %u times\n", __func__, cnt);
BUG_ON(cnt == 0 || cnt > 2);
}
LIVEPATCH_LOAD_HOOK(apply_hook);
LIVEPATCH_UNLOAD_HOOK(revert_hook);
/* Imbalance here. Two load and three unload. */
LIVEPATCH_LOAD_HOOK(hi_func);
LIVEPATCH_UNLOAD_HOOK(hi_func);
LIVEPATCH_UNLOAD_HOOK(check_fnc);
struct livepatch_func __section(".livepatch.funcs") livepatch_xen_hello_world = {
.version = LIVEPATCH_PAYLOAD_VERSION,
.name = hello_world_patch_this_fnc,
.new_addr = xen_hello_world,
.old_addr = xen_extra_version,
.new_size = NEW_CODE_SZ,
.old_size = OLD_CODE_SZ,
};
/*
* Local variables:
* mode: C
* c-file-style: "BSD"
* c-basic-offset: 4
* tab-width: 4
* indent-tabs-mode: nil
* End:
*/
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