From patchwork Mon Sep 10 10:42:41 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Thierry X-Patchwork-Id: 10593907 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0AD056CB for ; Mon, 10 Sep 2018 10:45:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E836528E08 for ; Mon, 10 Sep 2018 10:45:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D8BED28E26; Mon, 10 Sep 2018 10:45:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 6E93D28E08 for ; Mon, 10 Sep 2018 10:45:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=v4AO7I+5W3MnS9PMjpFODgdDfPrFyApyOq63WimqMI4=; b=p0HrosaJJWm5lqiY/YTQLdm9uL 9nzqXsj3oq10+O5NzgIdg+nhTruwqf8EAHGQzT8tHjbcrHDfSNvrIvMwiQ/PWnsdwR5ZmVwzghE5T aFnscbP8Xrffh14Fr1bF48TyLjTi6PRPH7FxKs1Esadl7eQuaEWQre4/D6RYwsR5cvJ1LcGy5w/Wg UHOA88y4qmlqslwKcWDLCExPmpEp8bsD3YJ9zqSynlkS4W6LDsoZltBR6poPjes0MATTXIy3eEBAa dKZXAkdbuK7AL1QvzwEwTgP0Q8xCYiohTQVmT9paNuj39kY6QzKUddu2d+R1vexvsTrsFxCl9//Bs ONUfXR1g==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1fzJhI-0005Bn-2L; Mon, 10 Sep 2018 10:45:36 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1fzJex-0002nq-3z for linux-arm-kernel@lists.infradead.org; Mon, 10 Sep 2018 10:43:14 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7372815BF; Mon, 10 Sep 2018 03:43:03 -0700 (PDT) Received: from e112298-lin.Emea.Arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 6037F3F575; Mon, 10 Sep 2018 03:43:02 -0700 (PDT) From: Julien Thierry To: linux-arm-kernel@lists.infradead.org, linux@armlinux.org.uk Subject: [PATCH v3 2/9] ARM: signal: always use __copy_to_user to save iwmmxt context Date: Mon, 10 Sep 2018 11:42:41 +0100 Message-Id: <1536576168-40096-3-git-send-email-julien.thierry@arm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1536576168-40096-1-git-send-email-julien.thierry@arm.com> References: <1536576168-40096-1-git-send-email-julien.thierry@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180910_034311_230199_0E175A55 X-CRM114-Status: GOOD ( 14.03 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, will.deacon@arm.com, Julien Thierry MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP When setting a dummy iwmmxt context, create a local instance and use __copy_to_user both cases whether iwmmxt is being used or not. This has the benefit of disabling/enabling PAN once for the whole copy intead of once per write. Signed-off-by: Julien Thierry --- arch/arm/kernel/signal.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 76fe75d..464393d 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -77,8 +77,6 @@ static int preserve_iwmmxt_context(struct iwmmxt_sigframe __user *frame) kframe->magic = IWMMXT_MAGIC; kframe->size = IWMMXT_STORAGE_SIZE; iwmmxt_task_copy(current_thread_info(), &kframe->storage); - - err = __copy_to_user(frame, kframe, sizeof(*frame)); } else { /* * For bug-compatibility with older kernels, some space @@ -86,10 +84,14 @@ static int preserve_iwmmxt_context(struct iwmmxt_sigframe __user *frame) * Set the magic and size appropriately so that properly * written userspace can skip it reliably: */ - __put_user_error(DUMMY_MAGIC, &frame->magic, err); - __put_user_error(IWMMXT_STORAGE_SIZE, &frame->size, err); + *kframe = (struct iwmmxt_sigframe) { + .magic = DUMMY_MAGIC, + .size = IWMMXT_STORAGE_SIZE, + }; } + err = __copy_to_user(frame, kframe, sizeof(*kframe)); + return err; }