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=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 C4F6FC433E0 for ; Mon, 1 Mar 2021 11:33:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8A49E64E40 for ; Mon, 1 Mar 2021 11:33:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233847AbhCALdc (ORCPT ); Mon, 1 Mar 2021 06:33:32 -0500 Received: from mail.kernel.org ([198.145.29.99]:57874 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233754AbhCALbc (ORCPT ); Mon, 1 Mar 2021 06:31:32 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 9757C64E22; Mon, 1 Mar 2021 11:30:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614598252; bh=XJHueoW65vLj+4kVOT6u/yTzg+bSjpuQ9NtCeZkqWGc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=EE4LqhTL0kSe1iVAk++5zkvFgXmp//BQRPuzNsxqY8miqRT2Q0wLWzHggHaaQZ4CR 9BW1BjOOfa5XTDzT+xyTN0j9uhXCWobMGzcRUNi4Jo6BcmlWbaa9+D3FC5KVC8un3N yF0bTRD5neVc+YxhDpu5KDuAbR1BNqTsUTz+4dbw= Date: Mon, 1 Mar 2021 12:30:49 +0100 From: Greg KH To: huangshaobo Cc: linux@arm.linux.org.uk, mhiramat@kernel.org, tixy@linaro.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, zengweilin@huawei.com, young.liuyang@huawei.com, nixiaoming@huawei.com, chenzefeng2@huawei.com, liucheng32@huawei.com, kepler.chenxin@huawei.com, xiaoqian9@huawei.com Subject: Re: [PATCH 4.4.y] arm: kprobes: Allow to handle reentered kprobe on single-stepping Message-ID: References: <20210227091701.23944-1-huangshaobo6@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210227091701.23944-1-huangshaobo6@huawei.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Feb 27, 2021 at 05:17:01PM +0800, huangshaobo wrote: > From: Masami Hiramatsu > > commit f3fbd7ec62dec1528fb8044034e2885f2b257941 upstream > > This is arm port of commit 6a5022a56ac3 ("kprobes/x86: Allow to > handle reentered kprobe on single-stepping") > > Since the FIQ handlers can interrupt in the single stepping > (or preparing the single stepping, do_debug etc.), we should > consider a kprobe is hit in the NMI handler. Even in that > case, the kprobe is allowed to be reentered as same as the > kprobes hit in kprobe handlers > (KPROBE_HIT_ACTIVE or KPROBE_HIT_SSDONE). > > The real issue will happen when a kprobe hit while another > reentered kprobe is processing (KPROBE_REENTER), because > we already consumed a saved-area for the previous kprobe. > > Signed-off-by: Masami Hiramatsu > Signed-off-by: Jon Medhurst > Fixes: 24ba613c9d6c ("ARM kprobes: core code") > Cc: stable@vger.kernel.org #v2.6.25~v4.11 > Signed-off-by: huangshaobo > --- > arch/arm/probes/kprobes/core.c | 6 ++++++ > 1 file changed, 6 insertions(+) What about the 4.9.y tree as well? thanks, greg k-h