Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755493AbcKVJ0O (ORCPT ); Tue, 22 Nov 2016 04:26:14 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:48789 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752774AbcKVJ0M (ORCPT ); Tue, 22 Nov 2016 04:26:12 -0500 From: Ravi Bangoria To: mpe@ellerman.id.au Cc: benh@kernel.crashing.org, paulus@samba.org, npiggin@gmail.com, peterz@infradead.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, naveen.n.rao@linux.vnet.ibm.com, Ravi Bangoria Subject: [PATCH] powerpc/xmon: Fix data-breakpoint Date: Tue, 22 Nov 2016 14:55:59 +0530 X-Mailer: git-send-email 2.1.4 X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16112209-0048-0000-0000-000001DE566C X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16112209-0049-0000-0000-000047062C7F Message-Id: <1479806759-5409-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-11-22_05:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1609300000 definitions=main-1611220171 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1096 Lines: 34 Xmon data-breakpoint feature is broken. Whenever there is a watchpoint match occurs, hw_breakpoint_handler will be called by do_break via notifier chains mechanism. If watchpoint is registered by xmon, hw_breakpoint_handler won't find any associated perf_event and returns immediately with NOTIFY_STOP. Similarly, do_break also returns without notifying to xmon. Solve this by returning NOTIFY_DONE when hw_breakpoint_handler does not find any perf_event associated with matched watchpoint. Signed-off-by: Ravi Bangoria --- arch/powerpc/kernel/hw_breakpoint.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c index 03d089b..469d86d 100644 --- a/arch/powerpc/kernel/hw_breakpoint.c +++ b/arch/powerpc/kernel/hw_breakpoint.c @@ -228,8 +228,10 @@ int hw_breakpoint_handler(struct die_args *args) rcu_read_lock(); bp = __this_cpu_read(bp_per_reg); - if (!bp) + if (!bp) { + rc = NOTIFY_DONE; goto out; + } info = counter_arch_bp(bp); /* -- 1.8.3.1