[PATCH] x86_64: Standardize i386/x86_64 handling of NMI_VECTOR
x86_64 and i386 behave inconsistently when sending an IPI on vector 2
(NMI_VECTOR). Make both behave the same, so IPI 2 is sent as NMI.
The crash code was abusing send_IPI_allbutself() by passing a code
instead of a vector, it only worked because crash knew about the
internal code of send_IPI_allbutself(). Change crash to use NMI_VECTOR
instead, and remove the comment about how crash was abusing the function.
This patch is a pre-requisite for fixing the problem where sending an
IPI as NMI would reboot some Dell Xeon systems. I cannot fix that
problem while crash continus to abuse send_IPI_allbutself().
It also removes the inconsistency between i386 and x86_64 for
NMI_VECTOR. That will simplify all the RAS code that needs to bring
all the cpus to a clean stop, even when one or more cpus are spinning
disabled.
Signed-off-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/i386/kernel/crash.c b/arch/i386/kernel/crash.c
index 21dc1bb..0c88d3e 100644
--- a/arch/i386/kernel/crash.c
+++ b/arch/i386/kernel/crash.c
@@ -120,14 +120,9 @@
return 1;
}
-/*
- * By using the NMI code instead of a vector we just sneak thru the
- * word generator coming out with just what we want. AND it does
- * not matter if clustered_apic_mode is set or not.
- */
static void smp_send_nmi_allbutself(void)
{
- send_IPI_allbutself(APIC_DM_NMI);
+ send_IPI_allbutself(NMI_VECTOR);
}
static void nmi_shootdown_cpus(void)
diff --git a/arch/i386/kernel/smp.c b/arch/i386/kernel/smp.c
index d134e96..c10789d 100644
--- a/arch/i386/kernel/smp.c
+++ b/arch/i386/kernel/smp.c
@@ -114,7 +114,17 @@
static inline int __prepare_ICR (unsigned int shortcut, int vector)
{
- return APIC_DM_FIXED | shortcut | vector | APIC_DEST_LOGICAL;
+ unsigned int icr = shortcut | APIC_DEST_LOGICAL;
+
+ switch (vector) {
+ default:
+ icr |= APIC_DM_FIXED | vector;
+ break;
+ case NMI_VECTOR:
+ icr |= APIC_DM_NMI;
+ break;
+ }
+ return icr;
}
static inline int __prepare_ICR2 (unsigned int mask)
diff --git a/arch/x86_64/kernel/crash.c b/arch/x86_64/kernel/crash.c
index ec1c743..8ca0491 100644
--- a/arch/x86_64/kernel/crash.c
+++ b/arch/x86_64/kernel/crash.c
@@ -118,7 +118,7 @@
static void smp_send_nmi_allbutself(void)
{
- send_IPI_allbutself(APIC_DM_NMI);
+ send_IPI_allbutself(NMI_VECTOR);
}
/*
diff --git a/include/asm-i386/hw_irq.h b/include/asm-i386/hw_irq.h
index 95d3fd0..a4c0a5a 100644
--- a/include/asm-i386/hw_irq.h
+++ b/include/asm-i386/hw_irq.h
@@ -19,6 +19,8 @@
struct hw_interrupt_type;
+#define NMI_VECTOR 0x02
+
/*
* Various low-level irq details needed by irq.c, process.c,
* time.c, io_apic.c and smp.c