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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 E6A80C54E8E for ; Mon, 11 May 2020 03:00:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C581124966 for ; Mon, 11 May 2020 03:00:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728686AbgEKDAd (ORCPT ); Sun, 10 May 2020 23:00:33 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:23766 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728612AbgEKDAa (ORCPT ); Sun, 10 May 2020 23:00:30 -0400 Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 04B2XCDL152682; Sun, 10 May 2020 23:00:05 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 30wrxywera-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sun, 10 May 2020 23:00:05 -0400 Received: from m0098417.ppops.net (m0098417.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 04B2pQ60194568; Sun, 10 May 2020 23:00:04 -0400 Received: from ppma04ams.nl.ibm.com (63.31.33a9.ip4.static.sl-reverse.com [169.51.49.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 30wrxywepw-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sun, 10 May 2020 23:00:04 -0400 Received: from pps.filterd (ppma04ams.nl.ibm.com [127.0.0.1]) by ppma04ams.nl.ibm.com (8.16.0.27/8.16.0.27) with SMTP id 04B2tH38029926; Mon, 11 May 2020 03:00:03 GMT Received: from b06avi18878370.portsmouth.uk.ibm.com (b06avi18878370.portsmouth.uk.ibm.com [9.149.26.194]) by ppma04ams.nl.ibm.com with ESMTP id 30wm55bfqs-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 11 May 2020 03:00:03 +0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06avi18878370.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 04B300EW55378220 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 11 May 2020 03:00:00 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1B68BAE055; Mon, 11 May 2020 03:00:00 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 800BBAE045; Mon, 11 May 2020 02:59:56 +0000 (GMT) Received: from bangoria.ibmuc.com (unknown [9.199.53.64]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 11 May 2020 02:59:56 +0000 (GMT) From: Ravi Bangoria To: mpe@ellerman.id.au, mikey@neuling.org Cc: apopple@linux.ibm.com, paulus@samba.org, npiggin@gmail.com, christophe.leroy@c-s.fr, naveen.n.rao@linux.vnet.ibm.com, peterz@infradead.org, jolsa@kernel.org, oleg@redhat.com, fweisbec@gmail.com, mingo@kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, ravi.bangoria@linux.ibm.com Subject: [PATCH v5 10/16] powerpc/watchpoint: Use loop for thread_struct->ptrace_bps Date: Mon, 11 May 2020 08:29:05 +0530 Message-Id: <20200511025911.212827-11-ravi.bangoria@linux.ibm.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200511025911.212827-1-ravi.bangoria@linux.ibm.com> References: <20200511025911.212827-1-ravi.bangoria@linux.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.216,18.0.676 definitions=2020-05-10_11:2020-05-08,2020-05-10 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 priorityscore=1501 mlxscore=0 clxscore=1015 lowpriorityscore=0 spamscore=0 suspectscore=0 mlxlogscore=999 malwarescore=0 impostorscore=0 bulkscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2005110017 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ptrace_bps is already an array of size HBP_NUM_MAX. But we use hardcoded index 0 while fetching/updating it. Convert such code to loop over array. ptrace interface to use multiple watchpoint remains same. eg: two PPC_PTRACE_SETHWDEBUG calls will create two watchpoint if underneath hw supports it. Signed-off-by: Ravi Bangoria Reviewed-by: Michael Neuling --- arch/powerpc/kernel/hw_breakpoint.c | 7 ++++-- arch/powerpc/kernel/process.c | 6 ++++- arch/powerpc/kernel/ptrace/ptrace-noadv.c | 28 +++++++++++++++++------ 3 files changed, 31 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c index 5826f1f2cab9..772b2c953220 100644 --- a/arch/powerpc/kernel/hw_breakpoint.c +++ b/arch/powerpc/kernel/hw_breakpoint.c @@ -419,10 +419,13 @@ NOKPROBE_SYMBOL(hw_breakpoint_exceptions_notify); */ void flush_ptrace_hw_breakpoint(struct task_struct *tsk) { + int i; struct thread_struct *t = &tsk->thread; - unregister_hw_breakpoint(t->ptrace_bps[0]); - t->ptrace_bps[0] = NULL; + for (i = 0; i < nr_wp_slots(); i++) { + unregister_hw_breakpoint(t->ptrace_bps[i]); + t->ptrace_bps[i] = NULL; + } } void hw_breakpoint_pmu_read(struct perf_event *bp) diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 6d1b7cede900..41a59a37383b 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1604,6 +1604,9 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long usp, void (*f)(void); unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE; struct thread_info *ti = task_thread_info(p); +#ifdef CONFIG_HAVE_HW_BREAKPOINT + int i; +#endif klp_init_thread_info(p); @@ -1663,7 +1666,8 @@ int copy_thread_tls(unsigned long clone_flags, unsigned long usp, p->thread.ksp_limit = (unsigned long)end_of_stack(p); #endif #ifdef CONFIG_HAVE_HW_BREAKPOINT - p->thread.ptrace_bps[0] = NULL; + for (i = 0; i < nr_wp_slots(); i++) + p->thread.ptrace_bps[i] = NULL; #endif p->thread.fp_save_area = NULL; diff --git a/arch/powerpc/kernel/ptrace/ptrace-noadv.c b/arch/powerpc/kernel/ptrace/ptrace-noadv.c index 0dbb35392dd2..08cb8c1b504c 100644 --- a/arch/powerpc/kernel/ptrace/ptrace-noadv.c +++ b/arch/powerpc/kernel/ptrace/ptrace-noadv.c @@ -168,6 +168,19 @@ int ptrace_set_debugreg(struct task_struct *task, unsigned long addr, unsigned l return 0; } +#ifdef CONFIG_HAVE_HW_BREAKPOINT +static int find_empty_ptrace_bp(struct thread_struct *thread) +{ + int i; + + for (i = 0; i < nr_wp_slots(); i++) { + if (!thread->ptrace_bps[i]) + return i; + } + return -1; +} +#endif + static int find_empty_hw_brk(struct thread_struct *thread) { int i; @@ -217,8 +230,9 @@ long ppc_set_hwdebug(struct task_struct *child, struct ppc_hw_breakpoint *bp_inf len = 1; else return -EINVAL; - bp = thread->ptrace_bps[0]; - if (bp) + + i = find_empty_ptrace_bp(thread); + if (i < 0) return -ENOSPC; /* Create a new breakpoint request if one doesn't exist already */ @@ -228,13 +242,13 @@ long ppc_set_hwdebug(struct task_struct *child, struct ppc_hw_breakpoint *bp_inf arch_bp_generic_fields(brk.type, &attr.bp_type); bp = register_user_hw_breakpoint(&attr, ptrace_triggered, NULL, child); - thread->ptrace_bps[0] = bp; + thread->ptrace_bps[i] = bp; if (IS_ERR(bp)) { - thread->ptrace_bps[0] = NULL; + thread->ptrace_bps[i] = NULL; return PTR_ERR(bp); } - return 1; + return i + 1; #endif /* CONFIG_HAVE_HW_BREAKPOINT */ if (bp_info->addr_mode != PPC_BREAKPOINT_MODE_EXACT) @@ -263,10 +277,10 @@ long ppc_del_hwdebug(struct task_struct *child, long data) return -EINVAL; #ifdef CONFIG_HAVE_HW_BREAKPOINT - bp = thread->ptrace_bps[0]; + bp = thread->ptrace_bps[data - 1]; if (bp) { unregister_hw_breakpoint(bp); - thread->ptrace_bps[0] = NULL; + thread->ptrace_bps[data - 1] = NULL; } else { ret = -ENOENT; } -- 2.21.1