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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
Subject: [Patch 7/10] Modify signal handling code to refrain from re-enabling HW Breakpoints
Date: Fri, 13 Feb 2009 20:28:00 +0530	[thread overview]
Message-ID: <20090213145800.GG32064@in.ibm.com> (raw)
In-Reply-To: <20090213145301.GA31546@in.ibm.com>


Modify signal handling code to refrain from re-enabling HW Breakpoints

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

This patch disables re-enabling of Hardware Breakpoint registers through
the  signal handling code. This is now done during
hw_breakpoint_handler().

Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
---
 arch/x86/kernel/signal.c |    9 ---------
 1 file changed, 9 deletions(-)

Index: linux-2.6-tip.hbkpt/arch/x86/kernel/signal.c
===================================================================
--- linux-2.6-tip.hbkpt.orig/arch/x86/kernel/signal.c
+++ linux-2.6-tip.hbkpt/arch/x86/kernel/signal.c
@@ -803,15 +803,6 @@ static void do_signal(struct pt_regs *re
 
 	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
 	if (signr > 0) {
-		/*
-		 * Re-enable any watchpoints before delivering the
-		 * signal to user space. The processor register will
-		 * have been cleared if the watchpoint triggered
-		 * inside the kernel.
-		 */
-		if (current->thread.debugreg7)
-			set_debugreg(current->thread.debugreg7, 7);
-
 		/* Whee! Actually deliver the signal.  */
 		if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
 			/*

  parent reply	other threads:[~2009-02-13 16:30 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-02-13 14:53 [Patch 00/10] Hardware Breakpoint interfaces K.Prasad
2009-02-13 14:54 ` [Patch 1/10] Introducing generic hardware breakpoint handler interfaces K.Prasad
2009-02-13 14:55 ` [Patch 2/10] x86 architecture implementation of Hardware Breakpoint interfaces K.Prasad
2009-02-13 14:55 ` [Patch 3/10] Modifying generic debug exception to use virtual debug registers K.Prasad
2009-02-13 14:56 ` [Patch 4/10] Introduce virtual debug register in thread_struct and wrapper-routines around process related functions K.Prasad
2009-02-13 14:56 ` [Patch 5/10] Use wrapper routines around debug registers in processor " K.Prasad
2009-02-13 14:57 ` [Patch 6/10] Use virtual debug registers in process/thread handling code K.Prasad
2009-02-13 14:58 ` K.Prasad [this message]
2009-02-13 14:58 ` [Patch 8/10] Modify Ptrace routines to access breakpoint registers K.Prasad
2009-02-13 14:59 ` [Patch 9/10] Cleanup HW Breakpoint registers before kexec K.Prasad
2009-02-13 14:59 ` [Patch 10/10] Sample HW breakpoint over kernel data address K.Prasad
     [not found]   ` <200902131138.41496.gene.heskett@verizon.net>
     [not found]     ` <20090214164456.GA5511@in.ibm.com>
     [not found]       ` <20090214224341.GA20477@elte.hu>
2009-02-15 10:27         ` K.Prasad
  -- strict thread matches above, loose matches on Subject: below --
2009-02-15 10:30 [Patch 00/10] Hardware Breakpoint interfaces K.Prasad
2009-02-15 10:34 ` [Patch 7/10] Modify signal handling code to refrain from re-enabling HW Breakpoints K.Prasad
2009-02-10 12:35 [Patch 0/10] Hardware Breakpoint interfaces - v2 K.Prasad
2009-02-10 12:43 ` [Patch 7/10] Modify signal handling code to refrain from re-enabling HW Breakpoints K.Prasad
2009-01-29  7:48 [Patch 0/10] Hardware Breakpoint interfaces K.Prasad
2009-01-29  8:30 ` [Patch 7/10] Modify signal handling code to refrain from re-enabling HW Breakpoints K.Prasad

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