[RFC Patch 9/10] Cleanup HW Breakpoint registers before kexec

K.Prasad
2009-01-22T14:10:35Z

This patch disables Hardware breakpoints before doing a 'kexec' on the machine.

Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
---
arch/x86/kernel/machine_kexec_32.c | 2 ++
arch/x86/kernel/machine_kexec_64.c | 2 ++
2 files changed, 4 insertions(+)

Index: linux-hbkpt-lkml-29-rc2/arch/x86/kernel/machine_kexec_32.c
===================================================================
--- linux-hbkpt-lkml-29-rc2.orig/arch/x86/kernel/machine_kexec_32.c
+++ linux-hbkpt-lkml-29-rc2/arch/x86/kernel/machine_kexec_32.c
@@ -25,6 +25,7 @@
#include <asm/desc.h>
#include <asm/system.h>
#include <asm/cacheflush.h>
+#include <asm/debugreg.h>

static void set_idt(void *newidt, __u16 limit)
{
@@ -202,6 +203,7 @@ void machine_kexec(struct kimage *image)

/* Interrupts aren't acceptable while we reboot */
local_irq_disable();
+ disable_debug_registers();

if (image->preserve_context) {
#ifdef CONFIG_X86_IO_APIC
Index: linux-hbkpt-lkml-29-rc2/arch/x86/kernel/machine_kexec_64.c
===================================================================
--- linux-hbkpt-lkml-29-rc2.orig/arch/x86/kernel/machine_kexec_64.c
+++ linux-hbkpt-lkml-29-rc2/arch/x86/kernel/machine_kexec_64.c
@@ -17,6 +17,7 @@
#include <asm/tlbflush.h>
#include <asm/mmu_context.h>
#include <asm/io.h>
+#include <asm/debugreg.h>

#define PAGE_ALIGNED __attribute__ ((__aligned__(PAGE_SIZE)))
static u64 kexec_pgd[512] PAGE_ALIGNED;
@@ -190,6 +191,7 @@ void machine_kexec(struct kimage *image)

/* Interrupts aren't acceptable while we reboot */
local_irq_disable();
+ disable_debug_registers();

control_page = page_address(image->control_code_page) + PAGE_SIZE;
memcpy(control_page, relocate_kernel, PAGE_SIZE);