X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=kernel%2Fsoftirq.c;h=787b3a032429a7a88321caf473f6f0e75d12da87;hb=483a53b310dfefdd8c010ba0cc5b2addfaef123f;hp=3d6833f125d307214bae0210bd68cbaaa925755d;hpb=3ad2e318a24124c53cc6390b5bfbd7613d9c2145;p=firefly-linux-kernel-4.4.55.git

diff --git a/kernel/softirq.c b/kernel/softirq.c
index 3d6833f125d3..787b3a032429 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -330,10 +330,19 @@ void irq_enter(void)
 
 static inline void invoke_softirq(void)
 {
-	if (!force_irqthreads)
-		__do_softirq();
-	else
+	if (!force_irqthreads) {
+		/*
+		 * We can safely execute softirq on the current stack if
+		 * it is the irq stack, because it should be near empty
+		 * at this stage. But we have no way to know if the arch
+		 * calls irq_exit() on the irq stack. So call softirq
+		 * in its own stack to prevent from any overrun on top
+		 * of a potentially deep task stack.
+		 */
+		do_softirq();
+	} else {
 		wakeup_softirqd();
+	}
 }
 
 static inline void tick_irq_exit(void)