From a696712c3dd54eb58d2c5a807b4aaa27782d80d6 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Mon, 17 Jul 2017 19:47:02 +0200 Subject: [PATCH] genirq/PM: Properly pretend disabled state when force resuming interrupts Interrupts with the IRQF_FORCE_RESUME flag set have also the IRQF_NO_SUSPEND flag set. They are not disabled in the suspend path, but must be forcefully resumed. That's used by XEN to keep IPIs enabled beyond the suspension of device irqs. Force resume works by pretending that the interrupt was disabled and then calling __irq_enable(). Incrementing the disabled depth counter was enough to do that, but with the recent changes which use state flags to avoid unnecessary hardware access, this is not longer sufficient. If the state flags are not set, then the hardware callbacks are not invoked and the interrupt line stays disabled in "hardware". Set the disabled and masked state when pretending that an interrupt got disabled by suspend. Fixes: bf22ff45bed6 ("genirq: Avoid unnecessary low level irq function calls") Suggested-by: Thomas Gleixner Signed-off-by: Juergen Gross Signed-off-by: Thomas Gleixner Cc: xen-devel@lists.xenproject.org Cc: boris.ostrovsky@oracle.com Link: http://lkml.kernel.org/r/20170717174703.4603-2-jgross@suse.com --- kernel/irq/chip.c | 10 ---------- kernel/irq/internals.h | 10 ++++++++++ kernel/irq/pm.c | 2 ++ 3 files changed, 12 insertions(+), 10 deletions(-) diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index d171bc57e1e0..a3cc37c0c85e 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -170,21 +170,11 @@ static void irq_state_clr_disabled(struct irq_desc *desc) irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED); } -static void irq_state_set_disabled(struct irq_desc *desc) -{ - irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED); -} - static void irq_state_clr_masked(struct irq_desc *desc) { irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED); } -static void irq_state_set_masked(struct irq_desc *desc) -{ - irqd_set(&desc->irq_data, IRQD_IRQ_MASKED); -} - static void irq_state_clr_started(struct irq_desc *desc) { irqd_clear(&desc->irq_data, IRQD_IRQ_STARTED); diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index dbfba9933ed2..a2c48058354c 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -227,6 +227,16 @@ static inline bool irqd_has_set(struct irq_data *d, unsigned int mask) return __irqd_to_state(d) & mask; } +static inline void irq_state_set_disabled(struct irq_desc *desc) +{ + irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED); +} + +static inline void irq_state_set_masked(struct irq_desc *desc) +{ + irqd_set(&desc->irq_data, IRQD_IRQ_MASKED); +} + #undef __irqd_to_state static inline void kstat_incr_irqs_this_cpu(struct irq_desc *desc) diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c index cea1de0161f1..6bd9b58429cc 100644 --- a/kernel/irq/pm.c +++ b/kernel/irq/pm.c @@ -149,6 +149,8 @@ static void resume_irq(struct irq_desc *desc) /* Pretend that it got disabled ! */ desc->depth++; + irq_state_set_disabled(desc); + irq_state_set_masked(desc); resume: desc->istate &= ~IRQS_SUSPENDED; __enable_irq(desc); -- 2.20.1