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-rw-r--r--kernel/hw_breakpoint.c3
-rw-r--r--kernel/kallsyms.c1
-rw-r--r--samples/hw_breakpoint/data_breakpoint.c43
3 files changed, 27 insertions, 20 deletions
diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c
index e662dc9..9ea9414 100644
--- a/kernel/hw_breakpoint.c
+++ b/kernel/hw_breakpoint.c
@@ -454,6 +454,7 @@ fail:
/* return the error if any */
return ERR_PTR(err);
}
+EXPORT_SYMBOL_GPL(register_wide_hw_breakpoint);
/**
* unregister_wide_hw_breakpoint - unregister a wide breakpoint in the kernel
@@ -470,7 +471,7 @@ void unregister_wide_hw_breakpoint(struct perf_event **cpu_events)
}
free_percpu(cpu_events);
}
-
+EXPORT_SYMBOL_GPL(unregister_wide_hw_breakpoint);
static struct notifier_block hw_breakpoint_exceptions_nb = {
.notifier_call = hw_breakpoint_exceptions_notify,
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 8b6b8b6..8e5288a 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -181,6 +181,7 @@ unsigned long kallsyms_lookup_name(const char *name)
}
return module_kallsyms_lookup_name(name);
}
+EXPORT_SYMBOL_GPL(kallsyms_lookup_name);
int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
unsigned long),
diff --git a/samples/hw_breakpoint/data_breakpoint.c b/samples/hw_breakpoint/data_breakpoint.c
index 9cbdbb8..5bc9819 100644
--- a/samples/hw_breakpoint/data_breakpoint.c
+++ b/samples/hw_breakpoint/data_breakpoint.c
@@ -27,18 +27,19 @@
#include <linux/module.h> /* Needed by all modules */
#include <linux/kernel.h> /* Needed for KERN_INFO */
#include <linux/init.h> /* Needed for the macros */
+#include <linux/kallsyms.h>
-#include <asm/hw_breakpoint.h>
+#include <linux/perf_event.h>
+#include <linux/hw_breakpoint.h>
-struct hw_breakpoint sample_hbp;
+struct perf_event **sample_hbp;
static char ksym_name[KSYM_NAME_LEN] = "pid_max";
module_param_string(ksym, ksym_name, KSYM_NAME_LEN, S_IRUGO);
MODULE_PARM_DESC(ksym, "Kernel symbol to monitor; this module will report any"
" write operations on the kernel symbol");
-void sample_hbp_handler(struct hw_breakpoint *temp, struct pt_regs
- *temp_regs)
+static void sample_hbp_handler(struct perf_event *temp, void *data)
{
printk(KERN_INFO "%s value is changed\n", ksym_name);
dump_stack();
@@ -48,30 +49,34 @@ void sample_hbp_handler(struct hw_breakpoint *temp, struct pt_regs
static int __init hw_break_module_init(void)
{
int ret;
+ unsigned long addr;
-#ifdef CONFIG_X86
- sample_hbp.info.name = ksym_name;
- sample_hbp.info.type = HW_BREAKPOINT_WRITE;
- sample_hbp.info.len = HW_BREAKPOINT_LEN_4;
-#endif /* CONFIG_X86 */
+ addr = kallsyms_lookup_name(ksym_name);
- sample_hbp.triggered = (void *)sample_hbp_handler;
+ sample_hbp = register_wide_hw_breakpoint(addr, HW_BREAKPOINT_LEN_4,
+ HW_BREAKPOINT_W | HW_BREAKPOINT_R,
+ sample_hbp_handler, true);
+ if (IS_ERR(sample_hbp)) {
+ ret = PTR_ERR(sample_hbp);
+ goto fail;
+ } else if (!sample_hbp) {
+ ret = -EINVAL;
+ goto fail;
+ }
- ret = register_kernel_hw_breakpoint(&sample_hbp);
-
- if (ret < 0) {
- printk(KERN_INFO "Breakpoint registration failed\n");
- return ret;
- } else
- printk(KERN_INFO "HW Breakpoint for %s write installed\n",
- ksym_name);
+ printk(KERN_INFO "HW Breakpoint for %s write installed\n", ksym_name);
return 0;
+
+fail:
+ printk(KERN_INFO "Breakpoint registration failed\n");
+
+ return ret;
}
static void __exit hw_break_module_exit(void)
{
- unregister_kernel_hw_breakpoint(&sample_hbp);
+ unregister_wide_hw_breakpoint(sample_hbp);
printk(KERN_INFO "HW Breakpoint for %s write uninstalled\n", ksym_name);
}
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