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From: prasad@linux.vnet.ibm.com
To: mingo@elte.hu
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Alan Stern <stern@rowland.harvard.edu>,
	Roland McGrath <roland@redhat.com>,
	"K.Prasad" <prasad@linux.vnet.ibm.com>
Subject: [Patch 07/11] Modify signal handling code to refrain from re-enabling HW Breakpoints
Date: Sat, 7 Mar 2009 10:36:55 +0530	[thread overview]
Message-ID: <20090307050655.GH23959@in.ibm.com> (raw)
In-Reply-To: 20090307045120.039324630@linux.vnet.ibm.com

[-- Attachment #1: 7 --]
[-- Type: text/plain, Size: 1126 bytes --]

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/arch/x86/kernel/signal.c
===================================================================
--- linux-2.6-tip.orig/arch/x86/kernel/signal.c
+++ linux-2.6-tip/arch/x86/kernel/signal.c
@@ -794,15 +794,6 @@ 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:[~2009-03-07  5:08 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20090307045120.039324630@linux.vnet.ibm.com>
2009-03-07  5:04 ` [Patch 01/11] Introducing generic hardware breakpoint handler interfaces prasad
2009-03-07  5:05 ` [Patch 02/11] x86 architecture implementation of Hardware Breakpoint interfaces prasad
2009-03-07  5:06 ` [Patch 03/11] Modifying generic debug exception to use virtual debug registers prasad
2009-03-07  5:06 ` [Patch 04/11] Introduce virtual debug register in thread_struct and wrapper-routines around process related functions prasad
2009-03-07  5:06 ` [Patch 05/11] Use wrapper routines around debug registers in processor " prasad
2009-03-07  5:06 ` [Patch 06/11] Use virtual debug registers in process/thread handling code prasad
2009-03-07  5:06 ` prasad [this message]
2009-03-07  5:07 ` [Patch 08/11] Modify Ptrace routines to access breakpoint registers prasad
2009-03-07  5:07 ` [Patch 09/11] Cleanup HW Breakpoint registers before kexec prasad
2009-03-07  5:07 ` [Patch 10/11] Sample HW breakpoint over kernel data address prasad
2009-03-07  5:07 ` [Patch 11/11] ftrace plugin for kernel symbol tracing using HW Breakpoint interfaces - v2 prasad
2009-03-07 14:53   ` KOSAKI Motohiro
2009-03-07 18:21     ` K.Prasad
2009-03-08 10:09     ` Ingo Molnar
2009-03-08 11:00       ` Frederic Weisbecker
2009-03-10 12:21         ` K.Prasad
2009-03-10 19:55           ` Frederic Weisbecker
2009-03-09 21:36       ` K.Prasad
     [not found] <20090407063058.301701787@prasadkr_t60p.in.ibm.com>
2009-04-07  6:36 ` [Patch 07/11] Modify signal handling code to refrain from re-enabling HW Breakpoints K.Prasad
     [not found] <20090324152028.754123712@K.Prasad>
2009-03-24 15:26 ` K.Prasad
     [not found] <20090319234044.410725944@K.Prasad>
2009-03-19 23:49 ` K.Prasad
     [not found] <20090305043440.189041194@linux.vnet.ibm.com>
2009-03-05  4:40 ` [patch " prasad

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