From patchwork Tue Jun 15 06:05:31 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "K.Prasad" X-Patchwork-Id: 55610 X-Patchwork-Delegate: paulus@samba.org 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 A327E101035 for ; Tue, 15 Jun 2010 16:05:59 +1000 (EST) Received: by ozlabs.org (Postfix) id 6F25B100AAF; Tue, 15 Jun 2010 16:05:37 +1000 (EST) Delivered-To: linuxppc-dev@ozlabs.org Received: from e28smtp01.in.ibm.com (e28smtp01.in.ibm.com [122.248.162.1]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e28smtp01.in.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id EE1B5100A4B for ; Tue, 15 Jun 2010 16:05:36 +1000 (EST) Received: from d28relay03.in.ibm.com (d28relay03.in.ibm.com [9.184.220.60]) by e28smtp01.in.ibm.com (8.14.4/8.13.1) with ESMTP id o5F65Xls010767 for ; Tue, 15 Jun 2010 11:35:33 +0530 Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay03.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o5F65XHK2842824 for ; Tue, 15 Jun 2010 11:35:33 +0530 Received: from d28av04.in.ibm.com (loopback [127.0.0.1]) by d28av04.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id o5F65WjW005970 for ; Tue, 15 Jun 2010 16:05:33 +1000 Received: from in.ibm.com ([9.124.35.44]) by d28av04.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id o5F65VAJ005951 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Tue, 15 Jun 2010 16:05:32 +1000 Date: Tue, 15 Jun 2010 11:35:31 +0530 From: "K.Prasad" To: "linuxppc-dev@ozlabs.org" , Paul Mackerras Subject: [Patch 3/5] PPC64-HWBKPT: Handle concurrent alignment interrupts Message-ID: <20100615060531.GD4790@in.ibm.com> References: <20100615055010.108795721@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Disposition: inline; filename=handle_alignment_interrupt_04 User-Agent: Mutt/1.5.20 (2009-12-10) 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. [The need to invoke single-step handler after alignment interrupt pointed out by Paul Mackerras ] Signed-off-by: K.Prasad --- arch/powerpc/kernel/traps.c | 8 +++----- 1 file changed, 3 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 +621,8 @@ 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); - } + if (single_stepping(regs)) + single_step_exception(regs); } static inline int __parse_fpscr(unsigned long fpscr)