softirq: Add debug check to __raise_softirq_irqoff()

JiafeiPan · KAGA-KOKO · commit cdabce2e3dff · 2020-09-16T15:18:56.000+02:00
__raise_softirq_irqoff() must be called with interrupts disabled to protect the per CPU softirq pending state update against an interrupt and soft interrupt handling on return from interrupt. Add a lockdep assertion to validate the calling convention. [ tglx: Massaged changelog ] Signed-off-by: Jiafei Pan <Jiafei.Pan@nxp.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20200814045522.45719-1-Jiafei.Pan@nxp.com
diff --git a/kernel/softirq.c b/kernel/softirq.c
@@ -481,6 +481,7 @@ void raise_softirq(unsigned int nr)
 
 void __raise_softirq_irqoff(unsigned int nr)
 {
+	lockdep_assert_irqs_disabled();
 	trace_softirq_raise(nr);
 	or_softirq_pending(1UL << nr);
 }

Original file line number	Diff line number	Diff line change
`@@ -481,6 +481,7 @@ void raise_softirq(unsigned int nr)`
`481`	`481`
`482`	`482`	`void __raise_softirq_irqoff(unsigned int nr)`
`483`	`483`	`{`
	`484`	`+ lockdep_assert_irqs_disabled();`
`484`	`485`	`trace_softirq_raise(nr);`
`485`	`486`	`or_softirq_pending(1UL << nr);`
`486`	`487`	`}`