Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fixes from Thomas Gleixner:
 "A rather large update after the kaisered maintainer finally found time
  to handle regression reports.

   - The larger part addresses a regression caused by the x86 vector
     management rework.

     The reservation based model does not work reliably for MSI
     interrupts, if they cannot be masked (yes, yet another hw
     engineering trainwreck). The reason is that the reservation mode
     assigns a dummy vector when the interrupt is allocated and switches
     to a real vector when the interrupt is requested.

     If the MSI entry cannot be masked then the initialization might
     raise an interrupt before the interrupt is requested, which ends up
     as spurious interrupt and causes device malfunction and worse. The
     fix is to exclude MSI interrupts which do not support masking from
     reservation mode and assign a real vector right away.

   - Extend the extra lockdep class setup for nested interrupts with a
     class for the recently added irq_desc::request_mutex so lockdep can
     differeniate and does not emit false positive warnings.

   - A ratelimit guard for the bad irq printout so in case a bad irq
     comes back immediately the system does not drown in dmesg spam"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/msi, x86/vector: Prevent reservation mode for non maskable MSI
  genirq/irqdomain: Rename early argument of irq_domain_activate_irq()
  x86/vector: Use IRQD_CAN_RESERVE flag
  genirq: Introduce IRQD_CAN_RESERVE flag
  genirq/msi: Handle reactivation only on success
  gpio: brcmstb: Make really use of the new lockdep class
  genirq: Guard handle_bad_irq log messages
  kernel/irq: Extend lockdep class for request mutex

6 files changed, 30 insertions, 16 deletions

diff --git a/arch/powerpc/sysdev/fsl_msi.c b/arch/powerpc/sysdev/fsl_msi.c
index 44cbf4c12ea1..df95102e732c 100644
--- a/arch/powerpc/sysdev/fsl_msi.c
+++ b/arch/powerpc/sysdev/fsl_msi.c
@@ -354,6 +354,7 @@ static int fsl_of_msi_remove(struct platform_device *ofdev)
 }
 
 static struct lock_class_key fsl_msi_irq_class;
+static struct lock_class_key fsl_msi_irq_request_class;
 
 static int fsl_msi_setup_hwirq(struct fsl_msi *msi, struct platform_device *dev,
 			       int offset, int irq_index)
@@ -373,7 +374,8 @@ static int fsl_msi_setup_hwirq(struct fsl_msi *msi, struct platform_device *dev,
 		dev_err(&dev->dev, "No memory for MSI cascade data\n");
 		return -ENOMEM;
 	}
-	irq_set_lockdep_class(virt_msir, &fsl_msi_irq_class);
+	irq_set_lockdep_class(virt_msir, &fsl_msi_irq_class,
+			      &fsl_msi_irq_request_class);
 	cascade_data->index = offset;
 	cascade_data->msi_data = msi;
 	cascade_data->virq = virt_msir;
diff --git a/arch/x86/include/asm/irqdomain.h b/arch/x86/include/asm/irqdomain.h
index 139feef467f7..c066ffae222b 100644
--- a/arch/x86/include/asm/irqdomain.h
+++ b/arch/x86/include/asm/irqdomain.h
@@ -44,7 +44,7 @@ extern int mp_irqdomain_alloc(struct irq_domain *domain, unsigned int virq,
 extern void mp_irqdomain_free(struct irq_domain *domain, unsigned int virq,
 			      unsigned int nr_irqs);
 extern int mp_irqdomain_activate(struct irq_domain *domain,
-				 struct irq_data *irq_data, bool early);
+				 struct irq_data *irq_data, bool reserve);
 extern void mp_irqdomain_deactivate(struct irq_domain *domain,
 				    struct irq_data *irq_data);
 extern int mp_irqdomain_ioapic_idx(struct irq_domain *domain);
diff --git a/arch/x86/include/asm/trace/irq_vectors.h b/arch/x86/include/asm/trace/irq_vectors.h
index 84b9ec0c1bc0..22647a642e98 100644
--- a/arch/x86/include/asm/trace/irq_vectors.h
+++ b/arch/x86/include/asm/trace/irq_vectors.h
@@ -283,34 +283,34 @@ TRACE_EVENT(vector_alloc_managed,
 DECLARE_EVENT_CLASS(vector_activate,
 
 	TP_PROTO(unsigned int irq, bool is_managed, bool can_reserve,
-		 bool early),
+		 bool reserve),
 
-	TP_ARGS(irq, is_managed, can_reserve, early),
+	TP_ARGS(irq, is_managed, can_reserve, reserve),
 
 	TP_STRUCT__entry(
 		__field(	unsigned int,	irq		)
 		__field(	bool,		is_managed	)
 		__field(	bool,		can_reserve	)
-		__field(	bool,		early		)
+		__field(	bool,		reserve		)
 	),
 
 	TP_fast_assign(
 		__entry->irq		= irq;
 		__entry->is_managed	= is_managed;
 		__entry->can_reserve	= can_reserve;
-		__entry->early		= early;
+		__entry->reserve	= reserve;
 	),
 
-	TP_printk("irq=%u is_managed=%d can_reserve=%d early=%d",
+	TP_printk("irq=%u is_managed=%d can_reserve=%d reserve=%d",
 		  __entry->irq, __entry->is_managed, __entry->can_reserve,
-		  __entry->early)
+		  __entry->reserve)
 );
 
 #define DEFINE_IRQ_VECTOR_ACTIVATE_EVENT(name)				\
 DEFINE_EVENT_FN(vector_activate, name,					\
 	TP_PROTO(unsigned int irq, bool is_managed,			\
-		 bool can_reserve, bool early),				\
-	TP_ARGS(irq, is_managed, can_reserve, early), NULL, NULL);	\
+		 bool can_reserve, bool reserve),			\
+	TP_ARGS(irq, is_managed, can_reserve, reserve), NULL, NULL);	\
 
 DEFINE_IRQ_VECTOR_ACTIVATE_EVENT(vector_activate);
 DEFINE_IRQ_VECTOR_ACTIVATE_EVENT(vector_deactivate);
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 201579dc5242..8a7963421460 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2988,7 +2988,7 @@ void mp_irqdomain_free(struct irq_domain *domain, unsigned int virq,
 }
 
 int mp_irqdomain_activate(struct irq_domain *domain,
-			  struct irq_data *irq_data, bool early)
+			  struct irq_data *irq_data, bool reserve)
 {
 	unsigned long flags;
 
diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index 750449152b04..f8b03bb8e725 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -184,6 +184,7 @@ static void reserve_irq_vector_locked(struct irq_data *irqd)
 	irq_matrix_reserve(vector_matrix);
 	apicd->can_reserve = true;
 	apicd->has_reserved = true;
+	irqd_set_can_reserve(irqd);
 	trace_vector_reserve(irqd->irq, 0);
 	vector_assign_managed_shutdown(irqd);
 }
@@ -368,8 +369,18 @@ static int activate_reserved(struct irq_data *irqd)
 	int ret;
 
 	ret = assign_irq_vector_any_locked(irqd);
-	if (!ret)
+	if (!ret) {
 		apicd->has_reserved = false;
+		/*
+		 * Core might have disabled reservation mode after
+		 * allocating the irq descriptor. Ideally this should
+		 * happen before allocation time, but that would require
+		 * completely convoluted ways of transporting that
+		 * information.
+		 */
+		if (!irqd_can_reserve(irqd))
+			apicd->can_reserve = false;
+	}
 	return ret;
 }
 
@@ -398,21 +409,21 @@ static int activate_managed(struct irq_data *irqd)
 }
 
 static int x86_vector_activate(struct irq_domain *dom, struct irq_data *irqd,
-			       bool early)
+			       bool reserve)
 {
 	struct apic_chip_data *apicd = apic_chip_data(irqd);
 	unsigned long flags;
 	int ret = 0;
 
 	trace_vector_activate(irqd->irq, apicd->is_managed,
-			      apicd->can_reserve, early);
+			      apicd->can_reserve, reserve);
 
 	/* Nothing to do for fixed assigned vectors */
 	if (!apicd->can_reserve && !apicd->is_managed)
 		return 0;
 
 	raw_spin_lock_irqsave(&vector_lock, flags);
-	if (early || irqd_is_managed_and_shutdown(irqd))
+	if (reserve || irqd_is_managed_and_shutdown(irqd))
 		vector_assign_managed_shutdown(irqd);
 	else if (apicd->is_managed)
 		ret = activate_managed(irqd);
@@ -478,6 +489,7 @@ static bool vector_configure_legacy(unsigned int virq, struct irq_data *irqd,
 	} else {
 		/* Release the vector */
 		apicd->can_reserve = true;
+		irqd_set_can_reserve(irqd);
 		clear_irq_vector(irqd);
 		realloc = true;
 	}
diff --git a/arch/x86/platform/uv/uv_irq.c b/arch/x86/platform/uv/uv_irq.c
index 5f6fd860820a..e4cb9f4cde8a 100644
--- a/arch/x86/platform/uv/uv_irq.c
+++ b/arch/x86/platform/uv/uv_irq.c
@@ -128,7 +128,7 @@ static void uv_domain_free(struct irq_domain *domain, unsigned int virq,
  * on the specified blade to allow the sending of MSIs to the specified CPU.
  */
 static int uv_domain_activate(struct irq_domain *domain,
-			      struct irq_data *irq_data, bool early)
+			      struct irq_data *irq_data, bool reserve)
 {
 	uv_program_mmr(irqd_cfg(irq_data), irq_data->chip_data);
 	return 0;