x86: mce: Serialize mce injection
raise_mce() fiddles with global state, but lacks any kind of
serialization.
Add a mutex around the raise_mce() call, so concurrent writers do not
stomp on each other toes.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Chen Gong <gong.chen@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/arch/x86/kernel/cpu/mcheck/mce-inject.c b/arch/x86/kernel/cpu/mcheck/mce-inject.c
index 753746f..ddc72f8 100644
--- a/arch/x86/kernel/cpu/mcheck/mce-inject.c
+++ b/arch/x86/kernel/cpu/mcheck/mce-inject.c
@@ -78,6 +78,7 @@
}
static cpumask_var_t mce_inject_cpumask;
+static DEFINE_MUTEX(mce_inject_mutex);
static int mce_raise_notify(unsigned int cmd, struct pt_regs *regs)
{
@@ -229,7 +230,10 @@
* so do it a jiffie or two later everywhere.
*/
schedule_timeout(2);
+
+ mutex_lock(&mce_inject_mutex);
raise_mce(&m);
+ mutex_unlock(&mce_inject_mutex);
return usize;
}