[PATCH] irqdomain: Do not reuse existing mappings
From: Alexander Gordeev
Date: Fri May 31 2013 - 08:58:34 EST
If a freshly acquired hardware interrupt number already mapped to
a Linux IRQ number it indicates a problem exists elsewhere, i.e.
a device driver did not dispose the mapping. Nevertheless, the
current code reuses such mappings and thus calls for more trouble.
This fix forces irq_create_mapping() to complain loudly and bail
out if an unexpected mapping detected.
Signed-off-by: Alexander Gordeev <agordeev@xxxxxxxxxx>
---
Documentation/IRQ-domain.txt | 7 +++----
arch/powerpc/platforms/44x/currituck.c | 1 +
arch/powerpc/platforms/maple/pci.c | 2 ++
arch/powerpc/platforms/pasemi/dma_lib.c | 1 +
arch/powerpc/platforms/pasemi/setup.c | 1 +
arch/powerpc/platforms/powermac/pci.c | 1 +
arch/powerpc/platforms/powermac/pic.c | 5 ++++-
arch/powerpc/platforms/powermac/smp.c | 6 +++++-
kernel/irq/irqdomain.c | 4 ++--
9 files changed, 20 insertions(+), 8 deletions(-)
diff --git a/Documentation/IRQ-domain.txt b/Documentation/IRQ-domain.txt
index 9bc9594..0ecef75 100644
--- a/Documentation/IRQ-domain.txt
+++ b/Documentation/IRQ-domain.txt
@@ -47,10 +47,9 @@ the .map callback populated as a minimum.
In most cases, the irq_domain will begin empty without any mappings
between hwirq and IRQ numbers. Mappings are added to the irq_domain
by calling irq_create_mapping() which accepts the irq_domain and a
-hwirq number as arguments. If a mapping for the hwirq doesn't already
-exist then it will allocate a new Linux irq_desc, associate it with
-the hwirq, and call the .map() callback so the driver can perform any
-required hardware setup.
+hwirq number as arguments. It will allocate a new Linux irq_desc,
+associate it with the hwirq, and call the .map() callback so the
+driver can perform any required hardware setup.
When an interrupt is received, irq_find_mapping() function should
be used to find the Linux IRQ number from the hwirq number.
diff --git a/arch/powerpc/platforms/44x/currituck.c b/arch/powerpc/platforms/44x/currituck.c
index ecd3890..5a8682d 100644
--- a/arch/powerpc/platforms/44x/currituck.c
+++ b/arch/powerpc/platforms/44x/currituck.c
@@ -182,6 +182,7 @@ static void ppc47x_pci_irq_fixup(struct pci_dev *dev)
if (dev->vendor == 0x1033 && (dev->device == 0x0035 ||
dev->device == 0x00e0)) {
dev->irq = irq_create_mapping(NULL, 47);
+ BUG_ON(dev->irq == NO_IRQ);
pr_info("%s: Mapping irq 47 %d\n", __func__, dev->irq);
}
}
diff --git a/arch/powerpc/platforms/maple/pci.c b/arch/powerpc/platforms/maple/pci.c
index f7136aa..482b69d 100644
--- a/arch/powerpc/platforms/maple/pci.c
+++ b/arch/powerpc/platforms/maple/pci.c
@@ -554,6 +554,8 @@ void maple_pci_irq_fixup(struct pci_dev *dev)
dev->irq = irq_create_mapping(NULL, 1);
if (dev->irq != NO_IRQ)
irq_set_irq_type(dev->irq, IRQ_TYPE_LEVEL_LOW);
+ else
+ WARN_ON(1);
}
/* Hide AMD8111 IDE interrupt when in legacy mode so
diff --git a/arch/powerpc/platforms/pasemi/dma_lib.c b/arch/powerpc/platforms/pasemi/dma_lib.c
index f3defd8..f05e66a0 100644
--- a/arch/powerpc/platforms/pasemi/dma_lib.c
+++ b/arch/powerpc/platforms/pasemi/dma_lib.c
@@ -212,6 +212,7 @@ void *pasemi_dma_alloc_chan(enum pasemi_dmachan_type type,
break;
}
+ BUG_ON(chan->irq == NO_IRQ);
chan->chan_type = type;
return chan;
diff --git a/arch/powerpc/platforms/pasemi/setup.c b/arch/powerpc/platforms/pasemi/setup.c
index 8c54de6d..54fa2d9 100644
--- a/arch/powerpc/platforms/pasemi/setup.c
+++ b/arch/powerpc/platforms/pasemi/setup.c
@@ -239,6 +239,7 @@ static __init void pas_init_IRQ(void)
/* The NMI/MCK source needs to be prio 15 */
if (nmiprop) {
nmi_virq = irq_create_mapping(NULL, *nmiprop);
+ BUG_ON(nmi_virq == NO_IRQ);
mpic_irq_set_priority(nmi_virq, 15);
irq_set_irq_type(nmi_virq, IRQ_TYPE_EDGE_RISING);
mpic_unmask_irq(irq_get_irq_data(nmi_virq));
diff --git a/arch/powerpc/platforms/powermac/pci.c b/arch/powerpc/platforms/powermac/pci.c
index cf7009b..07c3f2b 100644
--- a/arch/powerpc/platforms/powermac/pci.c
+++ b/arch/powerpc/platforms/powermac/pci.c
@@ -1002,6 +1002,7 @@ void pmac_pci_irq_fixup(struct pci_dev *dev)
dev->vendor == PCI_VENDOR_ID_DEC &&
dev->device == PCI_DEVICE_ID_DEC_TULIP_PLUS) {
dev->irq = irq_create_mapping(NULL, 60);
+ BUG_ON(dev->irq == NO_IRQ);
irq_set_irq_type(dev->irq, IRQ_TYPE_LEVEL_LOW);
}
#endif /* CONFIG_PPC32 */
diff --git a/arch/powerpc/platforms/powermac/pic.c b/arch/powerpc/platforms/powermac/pic.c
index 31036b5..f49706a 100644
--- a/arch/powerpc/platforms/powermac/pic.c
+++ b/arch/powerpc/platforms/powermac/pic.c
@@ -301,6 +301,7 @@ static void __init pmac_pic_probe_oldstyle(void)
struct device_node *slave = NULL;
u8 __iomem *addr;
struct resource r;
+ unsigned int virq;
/* Set our get_irq function */
ppc_md.get_irq = pmac_pic_get_irq;
@@ -389,7 +390,9 @@ static void __init pmac_pic_probe_oldstyle(void)
printk(KERN_INFO "irq: System has %d possible interrupts\n", max_irqs);
#ifdef CONFIG_XMON
- setup_irq(irq_create_mapping(NULL, 20), &xmon_action);
+ virq = irq_create_mapping(NULL, 20);
+ BUG_ON(virq == NO_IRQ);
+ setup_irq(virq, &xmon_action);
#endif
}
diff --git a/arch/powerpc/platforms/powermac/smp.c b/arch/powerpc/platforms/powermac/smp.c
index bdb738a..1c466f4 100644
--- a/arch/powerpc/platforms/powermac/smp.c
+++ b/arch/powerpc/platforms/powermac/smp.c
@@ -413,13 +413,17 @@ static struct irqaction psurge_irqaction = {
static void __init smp_psurge_setup_cpu(int cpu_nr)
{
+ unsigned int virq;
+
if (cpu_nr != 0 || !psurge_start)
return;
/* reset the entry point so if we get another intr we won't
* try to startup again */
out_be32(psurge_start, 0x100);
- if (setup_irq(irq_create_mapping(NULL, 30), &psurge_irqaction))
+ virq = irq_create_mapping(NULL, 30);
+ BUG_ON(virq == NO_IRQ);
+ if (setup_irq(virq, &psurge_irqaction))
printk(KERN_ERR "Couldn't get primary IPI interrupt");
}
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 5a83dde..ca662a2 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -580,8 +580,8 @@ unsigned int irq_create_mapping(struct irq_domain *domain,
/* Check if mapping already exists */
virq = irq_find_mapping(domain, hwirq);
if (virq) {
- pr_debug("-> existing mapping on virq %d\n", virq);
- return virq;
+ pr_warning("-> existing mapping on virq %d\n", virq);
+ return 0;
}
/* Get a virtual interrupt number */
--
1.7.7.6
--
Regards,
Alexander Gordeev
agordeev@xxxxxxxxxx
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