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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 8CF7BC282DD for ; Fri, 10 Jan 2020 18:42:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5BE232072E for ; Fri, 10 Jan 2020 18:42:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728665AbgAJSml (ORCPT ); Fri, 10 Jan 2020 13:42:41 -0500 Received: from foss.arm.com ([217.140.110.172]:49930 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728023AbgAJSml (ORCPT ); Fri, 10 Jan 2020 13:42:41 -0500 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 934AC30E; Fri, 10 Jan 2020 10:42:40 -0800 (PST) Received: from [10.1.197.1] (ewhatever.cambridge.arm.com [10.1.197.1]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4D6EA3F6C4; Fri, 10 Jan 2020 10:42:39 -0800 (PST) Subject: Re: [PATCH v2 5/7] arm64: ptrace: nofpsimd: Fail FP/SIMD regset operations To: Catalin Marinas Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, will@kernel.org, maz@kernel.org, mark.rutland@arm.com, dave.martin@arm.com, ard.biesheuvel@linaro.org, christoffer.dall@arm.com, Will Deacon References: <20191217183402.2259904-1-suzuki.poulose@arm.com> <20191217183402.2259904-6-suzuki.poulose@arm.com> <20200110151231.GG8786@arrakis.emea.arm.com> From: Suzuki Kuruppassery Poulose Message-ID: <2078734b-fba5-8207-a73a-3eee4b899256@arm.com> Date: Fri, 10 Jan 2020 18:42:38 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.3.1 MIME-Version: 1.0 In-Reply-To: <20200110151231.GG8786@arrakis.emea.arm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/01/2020 15:12, Catalin Marinas wrote: > On Tue, Dec 17, 2019 at 06:34:00PM +0000, Suzuki K Poulose wrote: >> diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c >> index 6771c399d40c..0135b944b8db 100644 >> --- a/arch/arm64/kernel/ptrace.c >> +++ b/arch/arm64/kernel/ptrace.c >> @@ -637,6 +637,9 @@ static int fpr_get(struct task_struct *target, const struct user_regset *regset, >> unsigned int pos, unsigned int count, >> void *kbuf, void __user *ubuf) >> { >> + if (!system_supports_fpsimd()) >> + return -EINVAL; >> + >> if (target == current) >> fpsimd_preserve_current_state(); > > I checked the coredump code (fill_thread_core_info) and works correctly > if we return -EINVAL here. But for completeness, we could add an > fpr_active() callback to aarch{32,64}_regsets (x86 does the same). > Sure, makes sense. I have now added fpr_active() hook for the FP regsets. Suzuki