From: Thomas Gleixner <tglx@linutronix.de> mainline inclusion from mainline-5.7 commit da90921acc62c71d27729ae211ccfda5370bf75b category: bugfix bugzilla: NA CVE: NA ------------------------------------------------- The code sets IRQS_REPLAY unconditionally whether the resend happens or not. That doesn't have bad side effects right now, but inconsistent state is always a latent source of problems. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lkml.kernel.org/r/20200306130623.882129117@linutronix.de Signed-off-by: Liao Chang <liaochang1@huawei.com> Reviewed-by: Hanjun Guo <guohanjun@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- kernel/irq/resend.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c index 1faf8991adbb5..7de48bc06c754 100644 --- a/kernel/irq/resend.c +++ b/kernel/irq/resend.c @@ -105,6 +105,7 @@ static int try_retrigger(struct irq_desc *desc) */ int check_irq_resend(struct irq_desc *desc) { + int err = 0; /* * We do not resend level type interrupts. Level type interrupts @@ -118,11 +119,16 @@ int check_irq_resend(struct irq_desc *desc) if (desc->istate & IRQS_REPLAY) return -EBUSY; - if (desc->istate & IRQS_PENDING) { - desc->istate &= ~IRQS_PENDING; + if (!(desc->istate & IRQS_PENDING)) + return 0; + + desc->istate &= ~IRQS_PENDING; + + if (!try_retrigger(desc)) + err = irq_sw_resend(desc); + + /* If the retrigger was successfull, mark it with the REPLAY bit */ + if (!err) desc->istate |= IRQS_REPLAY; - if (!try_retrigger(desc)) - return irq_sw_resend(desc); - } - return 0; + return err; } -- 2.25.1