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Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/mm/kmmio.c27
-rw-r--r--arch/x86/mm/mmio-mod.c2
2 files changed, 24 insertions, 5 deletions
diff --git a/arch/x86/mm/kmmio.c b/arch/x86/mm/kmmio.c
index a769d1a..256ce64 100644
--- a/arch/x86/mm/kmmio.c
+++ b/arch/x86/mm/kmmio.c
@@ -311,7 +311,12 @@ static int post_kmmio_handler(unsigned long condition, struct pt_regs *regs)
struct kmmio_context *ctx = &get_cpu_var(kmmio_ctx);
if (!ctx->active) {
- pr_debug("kmmio: spurious debug trap on CPU %d.\n",
+ /*
+ * debug traps without an active context are due to either
+ * something external causing them (f.e. using a debugger while
+ * mmio tracing enabled), or erroneous behaviour
+ */
+ pr_warning("kmmio: unexpected debug trap on CPU %d.\n",
smp_processor_id());
goto out;
}
@@ -529,8 +534,8 @@ void unregister_kmmio_probe(struct kmmio_probe *p)
}
EXPORT_SYMBOL(unregister_kmmio_probe);
-static int kmmio_die_notifier(struct notifier_block *nb, unsigned long val,
- void *args)
+static int
+kmmio_die_notifier(struct notifier_block *nb, unsigned long val, void *args)
{
struct die_args *arg = args;
@@ -545,11 +550,23 @@ static struct notifier_block nb_die = {
.notifier_call = kmmio_die_notifier
};
-static int __init init_kmmio(void)
+int kmmio_init(void)
{
int i;
+
for (i = 0; i < KMMIO_PAGE_TABLE_SIZE; i++)
INIT_LIST_HEAD(&kmmio_page_table[i]);
+
return register_die_notifier(&nb_die);
}
-fs_initcall(init_kmmio); /* should be before device_initcall() */
+
+void kmmio_cleanup(void)
+{
+ int i;
+
+ unregister_die_notifier(&nb_die);
+ for (i = 0; i < KMMIO_PAGE_TABLE_SIZE; i++) {
+ WARN_ONCE(!list_empty(&kmmio_page_table[i]),
+ KERN_ERR "kmmio_page_table not empty at cleanup, any further tracing will leak memory.\n");
+ }
+}
diff --git a/arch/x86/mm/mmio-mod.c b/arch/x86/mm/mmio-mod.c
index c9342ed..132772a 100644
--- a/arch/x86/mm/mmio-mod.c
+++ b/arch/x86/mm/mmio-mod.c
@@ -451,6 +451,7 @@ void enable_mmiotrace(void)
if (nommiotrace)
pr_info(NAME "MMIO tracing disabled.\n");
+ kmmio_init();
enter_uniprocessor();
spin_lock_irq(&trace_lock);
atomic_inc(&mmiotrace_enabled);
@@ -473,6 +474,7 @@ void disable_mmiotrace(void)
clear_trace_list(); /* guarantees: no more kmmio callbacks */
leave_uniprocessor();
+ kmmio_cleanup();
pr_info(NAME "disabled.\n");
out:
mutex_unlock(&mmiotrace_mutex);