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From: "K.Prasad" <prasad@linux.vnet.ibm.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Alan Stern <stern@rowland.harvard.edu>,
	Roland McGrath <roland@redhat.com>,
	richardj_moore@uk.ibm.com, jason.wessel@windriver.com,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: [Patch 9/10] Cleanup HW Breakpoint registers before kexec
Date: Sun, 15 Feb 2009 16:05:46 +0530	[thread overview]
Message-ID: <20090215103546.GJ6855@in.ibm.com> (raw)
In-Reply-To: <20090215103008.GA6855@in.ibm.com>


Cleanup HW Breakpoint registers before kexec

From: Alan Stern <stern@rowland.harvard.edu>

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

[K.Prasad: Split-out from the bigger patch and minor changes following
           re-basing]

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-2.6-tip.hbkpt/arch/x86/kernel/machine_kexec_32.c
===================================================================
--- linux-2.6-tip.hbkpt.orig/arch/x86/kernel/machine_kexec_32.c
+++ linux-2.6-tip.hbkpt/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-2.6-tip.hbkpt/arch/x86/kernel/machine_kexec_64.c
===================================================================
--- linux-2.6-tip.hbkpt.orig/arch/x86/kernel/machine_kexec_64.c
+++ linux-2.6-tip.hbkpt/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>
 
 static void init_level2_page(pmd_t *level2p, unsigned long addr)
 {
@@ -234,6 +235,7 @@ 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);

  parent reply	other threads:[~2009-02-15 10:36 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-02-15 10:30 [Patch 00/10] Hardware Breakpoint interfaces K.Prasad
2009-02-15 10:31 ` [Patch 1/10] Introducing generic hardware breakpoint handler interfaces K.Prasad
2009-02-15 10:32 ` [Patch 2/10] x86 architecture implementation of Hardware Breakpoint interfaces K.Prasad
2009-02-15 10:33 ` [Patch 3/10] Modifying generic debug exception to use virtual debug registers K.Prasad
2009-02-15 10:33 ` [Patch 4/10] Introduce virtual debug register in thread_struct and wrapper-routines around process related functions K.Prasad
2009-02-15 10:34 ` [Patch 5/10] Use wrapper routines around debug registers in processor " K.Prasad
2009-02-15 10:34 ` [Patch 6/10] Use virtual debug registers in process/thread handling code K.Prasad
2009-02-15 10:34 ` [Patch 7/10] Modify signal handling code to refrain from re-enabling HW Breakpoints K.Prasad
2009-02-15 10:35 ` [Patch 8/10] Modify Ptrace routines to access breakpoint registers K.Prasad
2009-02-15 10:35 ` K.Prasad [this message]
2009-02-15 10:36 ` [Patch 10/10] Sample HW breakpoint over kernel data address K.Prasad
  -- strict thread matches above, loose matches on Subject: below --
2009-02-13 14:53 [Patch 00/10] Hardware Breakpoint interfaces K.Prasad
2009-02-13 14:59 ` [Patch 9/10] Cleanup HW Breakpoint registers before kexec K.Prasad
2009-02-10 12:35 [Patch 0/10] Hardware Breakpoint interfaces - v2 K.Prasad
2009-02-10 12:44 ` [Patch 9/10] Cleanup HW Breakpoint registers before kexec K.Prasad
2009-01-29  7:48 [Patch 0/10] Hardware Breakpoint interfaces K.Prasad
2009-01-29  8:31 ` [Patch 9/10] Cleanup HW Breakpoint registers before kexec K.Prasad

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