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=-11.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 309EFC433E0 for ; Wed, 29 Jul 2020 10:46:07 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EF7AC207E8 for ; Wed, 29 Jul 2020 10:46:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="uVW2Bl+p" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EF7AC207E8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=hYuY9L5Or2jgT8n5VGoqRFB8bo3PhEgijNXrYOJ97rk=; b=uVW2Bl+pCHv88kuk1MVTVAkV2 2Rcth+Se6Ffs2PmjzszgjNLsd+HFOM9uIsi1Pdn8dvUZnMV94kjllRQb6lM/8KKiORl9YFHozeJwb 68wuIqW/AtkBkjQcGAI+GtQ0Ynxe2uW1Qy6fIYcHbGsvPCPz/DkVBpnyxruAHkOb/BWbRxYoKot7n XwigV7zaXyLRpITimVoee58T43MLS7ycgKgSv1fa5TfdaZ/WyExQoqVAZGE/iy6iT/eIW9DCJSP6/ b2eortEW7zbBKbWo9546GjA7zoQFGoweoZAtz6U2rur+ck32RLBJflQzPgSmTU+4Bd1oRyEbreREh ZXryl6rJQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k0jZl-0004oN-DA; Wed, 29 Jul 2020 10:44:45 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1k0jZi-0004nt-AK for linux-arm-kernel@lists.infradead.org; Wed, 29 Jul 2020 10:44:43 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AB9B030E; Wed, 29 Jul 2020 03:44:39 -0700 (PDT) Received: from arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5C3CB3F718; Wed, 29 Jul 2020 03:44:38 -0700 (PDT) Date: Wed, 29 Jul 2020 11:44:36 +0100 From: Dave Martin To: Amit Daniel Kachhap Subject: Re: [PATCH v4 4/4] arm64: kprobe: clarify the comment of steppable hint instructions Message-ID: <20200729104436.GE21941@arm.com> References: <1594368010-4419-1-git-send-email-amit.kachhap@arm.com> <1594368010-4419-5-git-send-email-amit.kachhap@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1594368010-4419-5-git-send-email-amit.kachhap@arm.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200729_064442_678524_FA18019D X-CRM114-Status: GOOD ( 21.79 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Kees Cook , Suzuki K Poulose , Catalin Marinas , Mark Brown , James Morse , Vincenzo Frascino , Will Deacon , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Jul 10, 2020 at 01:30:10PM +0530, Amit Daniel Kachhap wrote: > The existing comment about steppable hint instruction is not complete > and only describes NOP instructions as steppable. As the function > aarch64_insn_is_steppable_hint allows all white-listed instruction > to be probed so the comment is updated to reflect this. > > Signed-off-by: Amit Daniel Kachhap Reviewed-by: Dave Martin > --- > Changes since v3: > * New patch. > > arch/arm64/kernel/probes/decode-insn.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/kernel/probes/decode-insn.c b/arch/arm64/kernel/probes/decode-insn.c > index 263d5fba4c8a..3912a37cb117 100644 > --- a/arch/arm64/kernel/probes/decode-insn.c > +++ b/arch/arm64/kernel/probes/decode-insn.c > @@ -42,8 +42,10 @@ static bool __kprobes aarch64_insn_is_steppable(u32 insn) > != AARCH64_INSN_SPCLREG_DAIF; > > /* > - * The HINT instruction is is problematic when single-stepping, > - * except for the NOP case. > + * The HINT instruction is steppable only if it is in whitelist > + * and the rest of other such instructions are blocked for > + * single stepping as they may cause exception or other > + * unintended behaviour. > */ > if (aarch64_insn_is_hint(insn)) > return aarch64_insn_is_steppable_hint(insn); > -- > 2.17.1 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel