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=-15.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,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 4CE64C433DB for ; Thu, 18 Mar 2021 18:06:40 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 DF41264F10 for ; Thu, 18 Mar 2021 18:06:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DF41264F10 Authentication-Results: mail.kernel.org; dmarc=fail (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=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:Cc:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=RlnfmbUqqMFuWapRJuH4zhAGHe1oOisupXAKjA83OjQ=; b=d2kgAjJbI+f78jiVtpC7pAG+p aqV9f7TwTfEItfXvIiAqWCnrXZJki2ecxFmbBKhnKobd2ImYOX+XkWyrzP/rPMXmy+n268xeWJsWQ DHgqWDN8iqnwgoN7rvBLmL03rKJVFQTbeQ8ejnaO+xZt6PgdtBlDg1OV4AGZU0rbEzEldW+2e4SYT 57qbYdrge3Ljbbn5Hc1RRGoVjMOq+L3itSG9XFBlIvwa/cy/5ZDriDt6rCDtlODcg/j3F0h+26Anr 2ILuwmoBF/jlEy3kadkIGHDqBKOH8PRvpbMuXI39N9VQUk5w6SkI0idcuw4USVd/Pru1/AG79lkt8 UKvZZH7YA==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lMx1R-005nfh-Ns; Thu, 18 Mar 2021 18:05:25 +0000 Received: from foss.arm.com ([217.140.110.172]) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lMx1L-005neR-6r for linux-arm-kernel@lists.infradead.org; Thu, 18 Mar 2021 18:05:23 +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 516D831B; Thu, 18 Mar 2021 11:05:08 -0700 (PDT) Received: from [10.37.12.7] (unknown [10.37.12.7]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 429883F70D; Thu, 18 Mar 2021 11:05:07 -0700 (PDT) Subject: Re: [PATCH 2/5] arm64: vdso: Remove redundant calls to flush_dcache_page() To: Will Deacon , linux-arm-kernel@lists.infradead.org Cc: kernel-team@android.com, Catalin Marinas , Mark Rutland , Marc Zyngier , Russell King References: <20210318170738.7756-1-will@kernel.org> <20210318170738.7756-3-will@kernel.org> From: Vincenzo Frascino Message-ID: <4f7bc394-f4b1-bcee-29ef-f34af4803102@arm.com> Date: Thu, 18 Mar 2021 18:05:06 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210318170738.7756-3-will@kernel.org> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210318_180519_462159_72D1ECBC X-CRM114-Status: GOOD ( 17.65 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 3/18/21 5:07 PM, Will Deacon wrote: > flush_dcache_page() ensures that the 'PG_dcache_clean' flag for its > 'page' argument is clear so that cache maintenance will be performed > if the page is mapped into userspace with execute permissions. > > Newly allocated pages have this flag clear, so there is no need to call > flush_dcache_page() for the compat vdso or signal pages. Remove the > redundant calls. > > Signed-off-by: Will Deacon Reviewed-by: Vincenzo Frascino > --- > arch/arm64/kernel/vdso.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c > index 2d057a4dc787..421411981dc3 100644 > --- a/arch/arm64/kernel/vdso.c > +++ b/arch/arm64/kernel/vdso.c > @@ -306,7 +306,6 @@ static int aarch32_alloc_kuser_vdso_page(void) > memcpy((void *)(vdso_page + 0x1000 - kuser_sz), __kuser_helper_start, > kuser_sz); > aarch32_vectors_page = virt_to_page(vdso_page); > - flush_dcache_page(aarch32_vectors_page); > return 0; > } > > @@ -322,7 +321,6 @@ static int aarch32_alloc_sigpage(void) > > memcpy((void *)sigpage, __aarch32_sigret_code_start, sigret_sz); > aarch32_sig_page = virt_to_page(sigpage); > - flush_dcache_page(aarch32_sig_page); > return 0; > } > > -- Regards, Vincenzo _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel