1 files changed, 3 insertions, 0 deletions

diff --git a/arch/powerpc/sysdev/uic.c b/arch/powerpc/sysdev/uic.c
index 22c219e448..47180b3fca 100644
--- a/arch/powerpc/sysdev/uic.c
+++ b/arch/powerpc/sysdev/uic.c
@@ -266,6 +266,9 @@ irqreturn_t uic_cascade(int virq, void *data)
         int subvirq;
 
         msr = mfdcr(uic->dcrbase + UIC_MSR);
+        if (!msr) /* spurious interrupt */
+                return IRQ_HANDLED;
+
         src = 32 - ffs(msr);
 
         subvirq = irq_linear_revmap(uic->irqhost, src);