hw-breakpoints: cleanup HW Breakpoint registers before kexec

This patch disables Hardware breakpoints before doing a 'kexec' on the machine so that the cpu doesn't keep debug registers values which would be out of sync for the new image. Original-patch-by: Alan Stern <[email protected]> Signed-off-by: K.Prasad <[email protected]> Reviewed-by: Alan Stern <[email protected]> Signed-off-by: Frederic Weisbecker <[email protected]>
niw · Jun 2, 2009 · 17f557e · 17f557e
1 parent 72f674d
commit 17f557e
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diff --git a/arch/x86/kernel/machine_kexec_32.c b/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();
+	hw_breakpoint_disable();
 
 	if (image->preserve_context) {
 #ifdef CONFIG_X86_IO_APIC

diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
@@ -18,6 +18,7 @@
 #include <asm/pgtable.h>
 #include <asm/tlbflush.h>
 #include <asm/mmu_context.h>
+#include <asm/debugreg.h>
 
 static int init_one_level2_page(struct kimage *image, pgd_t *pgd,
 				unsigned long addr)
@@ -282,6 +283,7 @@ void machine_kexec(struct kimage *image)
 
 	/* Interrupts aren't acceptable while we reboot */
 	local_irq_disable();
+	hw_breakpoint_disable();
 
 	if (image->preserve_context) {
 #ifdef CONFIG_X86_IO_APIC