From: Eric W. Biederman <ebiederm@xmission.com>
As pointed out and tracked by Yinghai Lu <yhlu.kernel@gmail.com>:
Dhaval Giani got:
kernel BUG at arch/x86/kernel/io_apic_64.c:357!
invalid opcode: 0000 [1] SMP
CPU 24
...
his system (x3950) has 8 ioapic, irq > 256
This was caused by:
commit 9b7dc567d03d74a1fbae84e88949b6a60d922d82
Author: Thomas Gleixner <tglx@linutronix.de>
Date: Fri May 2 20:10:09 2008 +0200
x86: unify interrupt vector defines
The interrupt vector defines are copied 4 times around with minimal
differences. Move them all into asm-x86/irq_vectors.h
It appears that Thomas did not notice that x86_64 does something
completely different when he merge irq_vectors.h
We can solve this for 2.6.27 by simply reintroducing the old heuristic
for setting NR_IRQS on x86_64 to a usable value, which trivially removes
the regression.
Long term it would be nice to harmonize the handling of ioapic interrupts
of x86_32 and x86_64 so we don't have this kind of confusion.
Dhaval Giani <dhaval@linux.vnet.ibm.com> tested an earlier version of
this patch by YH which confirms simply increasing NR_IRQS fixes the
problem.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---
include/asm-x86/irq_vectors.h | 10 +++++++++-
1 files changed, 9 insertions(+), 1 deletions(-)
diff --git a/include/asm-x86/irq_vectors.h b/include/asm-x86/irq_vectors.h
index 646d59f..3f4b1b6 100644
--- a/include/asm-x86/irq_vectors.h
+++ b/include/asm-x86/irq_vectors.h
@@ -109,7 +109,15 @@
#define LAST_VM86_IRQ 15
#define invalid_vm86_irq(irq) ((irq) < 3 || (irq) > 15)
-#if !defined(CONFIG_X86_VOYAGER)
+#ifdef CONFIG_X86_64
+# if NR_CPUS < MAX_IO_APICS
+# define NR_IRQS (NR_VECTORS + (32 * NR_CPUS))
+# else
+# define NR_IRQS (NR_VECTORS + (32 * MAX_IO_APICS))
+# endif
+# define NR_IRQ_VECTORS NR_IRQS
+
+#elif !defined(CONFIG_X86_VOYAGER)
# if defined(CONFIG_X86_IO_APIC) || defined(CONFIG_PARAVIRT) || defined(CONFIG_X86_VISWS)
--
1.5.4.5
--
