From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3587CC46464 for ; Thu, 9 Aug 2018 12:03:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EC80C2150A for ; Thu, 9 Aug 2018 12:03:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EC80C2150A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731111AbeHIO1o (ORCPT ); Thu, 9 Aug 2018 10:27:44 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:34200 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730261AbeHIO1o (ORCPT ); Thu, 9 Aug 2018 10:27:44 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0D86840216E8; Thu, 9 Aug 2018 12:03:10 +0000 (UTC) Received: from krava.brq.redhat.com (unknown [10.43.17.133]) by smtp.corp.redhat.com (Postfix) with ESMTP id 32C2F10FFE6F; Thu, 9 Aug 2018 12:03:06 +0000 (UTC) From: Jiri Olsa To: Arnaldo Carvalho de Melo Cc: lkml , Ingo Molnar , Namhyung Kim , David Ahern , Alexander Shishkin , Peter Zijlstra , Milind Chabbi , Oleg Nesterov , Frederic Weisbecker Subject: [PATCHv2 0/5] perf/hw_breakpoint: Fix breakpoint modify Date: Thu, 9 Aug 2018 14:03:00 +0200 Message-Id: <20180809120305.20693-1-jolsa@kernel.org> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Thu, 09 Aug 2018 12:03:10 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.5]); Thu, 09 Aug 2018 12:03:10 +0000 (UTC) for IP:'10.11.54.3' DOMAIN:'int-mx03.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'jolsa@kernel.org' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org hi, Milind reported that modify_user_hw_breakpoint wouldn't allow the breakpoint changing if the new attr had 'disabled' set to true. I found a case where it actualy prevents ptrace user interface to change the breakpoint. It's described in patch 1 as perf test, patch 2 is the breakpoint code fix. I ran strace tests, nothing (new) broken there.. v2 changes: - added Oleg's ack for patch 2 - added new changes based on Oleg's questions plus new test code thanks, jirka --- Jiri Olsa (5): perf tests: Add breakpoint modify tests perf/hw_breakpoint: Modify breakpoint even if the new attr has disabled set perf/hw_breakpoint: Remove superfluous bp->attr.disabled = 0 perf/hw_breakpoint: Set breakpoint as disabled in modify_user_hw_breakpoint error path perf/hw_breakpoint: Add fallback code for ptrace_set_breakpoint_addr arch/x86/kernel/ptrace.c | 5 +++ kernel/events/hw_breakpoint.c | 15 +++++---- tools/perf/arch/x86/include/arch-tests.h | 1 + tools/perf/arch/x86/tests/Build | 1 + tools/perf/arch/x86/tests/arch-tests.c | 6 ++++ tools/perf/arch/x86/tests/bp-modify.c | 213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 6 files changed, 235 insertions(+), 6 deletions(-) create mode 100644 tools/perf/arch/x86/tests/bp-modify.c