x86: mce: clear injection state after eventmce/injector

Currently when an event is ever injected the machine
check code will never read the hardware registers
again, but always only look at the fake software
injection registers.

Clear the injection state after an event has been
processed. This way normal hardware events will
be processed again after injection.

Signed-off-by: Andi Kleen <ak@linux.intel.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 2cd0a5182bfe0..9a70b10c28304 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -379,6 +379,18 @@ static void mce_wrmsrl(u32 msr, u64 v)
 	wrmsrl(msr, v);
 }
 
+/* 
+ * Switch back to processing hardware events after finishing 
+ * an injected event.
+ */
+static void mce_end_injection(unsigned long *b)
+{
+	struct mce *m = &__get_cpu_var(injectm);
+
+	if (m->finished && test_bit(m->bank, b))
+		m->finished = 0;
+}
+
 /*
  * Simple lockless ring to communicate PFNs from the exception handler with the
  * process context work function. This is vastly simplified because there's
@@ -598,6 +610,8 @@ void machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
 		mce_wrmsrl(MSR_IA32_MCx_STATUS(i), 0);
 	}
 
+	mce_end_injection(*b);
+
 	/*
 	 * Don't clear MCG_STATUS here because it's only defined for
 	 * exceptions.
@@ -1081,6 +1095,7 @@ void do_machine_check(struct pt_regs *regs, long error_code)
 	if (worst > 0)
 		mce_report_event(regs);
 	mce_wrmsrl(MSR_IA32_MCG_STATUS, 0);
+	mce_end_injection(toclear);
 out:
 	atomic_dec(&mce_entry);
 	sync_core();