From patchwork Tue May 25 09:14:35 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "K.Prasad" X-Patchwork-Id: 53520 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from bilbo.ozlabs.org (localhost [127.0.0.1]) by ozlabs.org (Postfix) with ESMTP id 9F960B8B27 for ; Tue, 25 May 2010 19:15:01 +1000 (EST) Received: by ozlabs.org (Postfix) id 4B370B86D9; Tue, 25 May 2010 19:14:42 +1000 (EST) Delivered-To: linuxppc-dev@ozlabs.org Received: from e23smtp08.au.ibm.com (e23smtp08.au.ibm.com [202.81.31.141]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e23smtp08.au.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 43F35B86D6 for ; Tue, 25 May 2010 19:14:42 +1000 (EST) Received: from d23relay04.au.ibm.com (d23relay04.au.ibm.com [202.81.31.246]) by e23smtp08.au.ibm.com (8.14.3/8.13.1) with ESMTP id o4P9Ed9R010636 for ; Tue, 25 May 2010 19:14:39 +1000 Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay04.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o4P9EfgO1609968 for ; Tue, 25 May 2010 19:14:41 +1000 Received: from d23av02.au.ibm.com (loopback [127.0.0.1]) by d23av02.au.ibm.com (8.14.3/8.13.1/NCO v10.0 AVout) with ESMTP id o4P9Ee5o005787 for ; Tue, 25 May 2010 19:14:40 +1000 Received: from in.ibm.com ([9.124.35.26]) by d23av02.au.ibm.com (8.14.3/8.13.1/NCO v10.0 AVin) with ESMTP id o4P9EZKp005722 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Tue, 25 May 2010 19:14:38 +1000 Date: Tue, 25 May 2010 14:44:35 +0530 From: "K.Prasad" To: "linuxppc-dev@ozlabs.org" , Paul Mackerras Subject: [Patch 3/4] PPC64-HWBKPT: Handle concurrent alignment interrupts Message-ID: <20100525091435.GD29003@in.ibm.com> References: <20100525083055.342788418@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Disposition: inline; filename=handle_alignment_interrupt_04 User-Agent: Mutt/1.5.19 (2009-01-05) Cc: Michael Neuling , Benjamin Herrenschmidt , shaggy@linux.vnet.ibm.com, Frederic Weisbecker , David Gibson , Alan Stern , "K.Prasad" , Roland McGrath X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org An alignment interrupt may intervene between a DSI/hw-breakpoint exception and the single-step exception. Enable the alignment interrupt (through modifications to emulate_single_step()) to notify the single-step exception handler for proper restoration of hw-breakpoints. Signed-off-by: K.Prasad --- arch/powerpc/kernel/traps.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) Index: linux-2.6.ppc64_test/arch/powerpc/kernel/traps.c =================================================================== --- linux-2.6.ppc64_test.orig/arch/powerpc/kernel/traps.c +++ linux-2.6.ppc64_test/arch/powerpc/kernel/traps.c @@ -602,7 +602,7 @@ void RunModeException(struct pt_regs *re void __kprobes single_step_exception(struct pt_regs *regs) { - regs->msr &= ~(MSR_SE | MSR_BE); /* Turn off 'trace' bits */ + clear_single_step(regs); if (notify_die(DIE_SSTEP, "single_step", regs, 5, 5, SIGTRAP) == NOTIFY_STOP) @@ -621,10 +621,7 @@ void __kprobes single_step_exception(str */ static void emulate_single_step(struct pt_regs *regs) { - if (single_stepping(regs)) { - clear_single_step(regs); - _exception(SIGTRAP, regs, TRAP_TRACE, 0); - } + single_step_exception(regs); } static inline int __parse_fpscr(unsigned long fpscr)