From: long <tlnguyen@snoqualmie.dp.intel.com>
I did some MSI tests on 2.6.5-mm3 and observed the followings:
- CONFIG_PCI_USE_VECTOR = y in both UP and SMP ==> PASS
- CONFIG_PCI_USE_VECTOR = n in UP and SMP ==> SYSTEM HANGS!
This is becasue NR_IRQ_VECTORS, which was defined as NR_VECTORS (256) was
changed to NR_IRQS (224).
As a result of this change, the vector allocator assign_irq_vector in
arch/i386/kernel/io_apic.c will hang the system when assigned vector is
greater than 224, like 238 for example since vector_irq[] has only 224
elements.
---
25-akpm/arch/i386/kernel/io_apic.c | 2 +-
25-akpm/drivers/pci/msi.c | 2 +-
25-akpm/drivers/pci/msi.h | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)
diff -puN arch/i386/kernel/io_apic.c~ia32-msi-fixup arch/i386/kernel/io_apic.c
--- 25/arch/i386/kernel/io_apic.c~ia32-msi-fixup Fri Apr 9 16:06:58 2004
+++ 25-akpm/arch/i386/kernel/io_apic.c Fri Apr 9 16:06:58 2004
@@ -76,7 +76,7 @@ static struct irq_pin_list {
int apic, pin, next;
} irq_2_pin[PIN_MAP_SIZE];
-int vector_irq[NR_IRQ_VECTORS] = { [0 ... NR_IRQ_VECTORS - 1] = -1};
+int vector_irq[NR_VECTORS] = { [0 ... NR_VECTORS - 1] = -1};
#ifdef CONFIG_PCI_USE_VECTOR
#define vector_to_irq(vector) \
(platform_legacy_irq(vector) ? vector : vector_irq[vector])
diff -puN drivers/pci/msi.c~ia32-msi-fixup drivers/pci/msi.c
--- 25/drivers/pci/msi.c~ia32-msi-fixup Fri Apr 9 16:06:58 2004
+++ 25-akpm/drivers/pci/msi.c Fri Apr 9 16:06:58 2004
@@ -33,7 +33,7 @@ static int nr_reserved_vectors = NR_HP_R
static int nr_msix_devices = 0;
#ifndef CONFIG_X86_IO_APIC
-int vector_irq[NR_IRQ_VECTORS] = { [0 ... NR_IRQ_VECTORS - 1] = -1};
+int vector_irq[NR_VECTORS] = { [0 ... NR_VECTORS - 1] = -1};
u8 irq_vector[NR_IRQ_VECTORS] = { FIRST_DEVICE_VECTOR , 0 };
#endif
diff -puN drivers/pci/msi.h~ia32-msi-fixup drivers/pci/msi.h
--- 25/drivers/pci/msi.h~ia32-msi-fixup Fri Apr 9 16:06:58 2004
+++ 25-akpm/drivers/pci/msi.h Fri Apr 9 16:06:58 2004
@@ -18,7 +18,7 @@
*/
#define NR_HP_RESERVED_VECTORS 20
-extern int vector_irq[NR_IRQ_VECTORS];
+extern int vector_irq[NR_VECTORS];
extern cpumask_t pending_irq_balance_cpumask[NR_IRQS];
extern void (*interrupt[NR_IRQS])(void);
extern int pci_vector_resources(int last, int nr_released);
_