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=-9.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,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 5D966C4727E for ; Wed, 30 Sep 2020 17:15:33 +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 F2C90207FB for ; Wed, 30 Sep 2020 17:15:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="K8v1gWlB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F2C90207FB 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=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=O4oj8yJLATvWdB4ZDhF3WxP4hifG/9SXLUQdW4PwRhk=; b=K8v1gWlBh0KJ3sS7YEPWVGwgJ s3JzQCnz8EGMJOHa02j1Zpy/dpfEEQla7ekpQ3CSv1kSBChBP0IU9NXiB/cbOHdcebzvP+CivM/9q 2SdMvXSxJmuJ+oyTgXKqb1+tRRbfWIEtEqoPqvgaeWU6phTp/hRmqHK+xr4EfSQA8UBsHEGLQvWz8 Hrnm+WzQHyzNMEPvdouXkWXTAVEgm9A8X8R3SG3gUSt1kbAlHpTQ0z9oyLTU4pgGEha34qk34Gonw 76c4iez7+cSvUjYTGT6XUMizLegGf3uIk68jpUKnKwuW07NjpWMit2H2BzG8eNBSSomoDRUv7nuLR 0rojz0Anw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kNfgB-0004kU-9J; Wed, 30 Sep 2020 17:14:11 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kNfg9-0004ju-2Q for linux-arm-kernel@lists.infradead.org; Wed, 30 Sep 2020 17:14:09 +0000 Received: from gaia (unknown [31.124.44.166]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 245352076B; Wed, 30 Sep 2020 17:14:06 +0000 (UTC) Date: Wed, 30 Sep 2020 18:14:04 +0100 From: Catalin Marinas To: Will Deacon Subject: Re: [PATCH] arm64: mm: Make flush_tlb_fix_spurious_fault() a no-op Message-ID: <20200930171403.GA29503@gaia> References: <20200930131859.16989-1-will@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200930131859.16989-1-will@kernel.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200930_131409_188076_4B92DC87 X-CRM114-Status: GOOD ( 14.04 ) 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: kernel-team@android.com, linux-kernel@vger.kernel.org, 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 Wed, Sep 30, 2020 at 02:18:59PM +0100, Will Deacon wrote: > diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c > index f07333e86c2f..a696a7921da4 100644 > --- a/arch/arm64/mm/fault.c > +++ b/arch/arm64/mm/fault.c > @@ -218,7 +218,9 @@ int ptep_set_access_flags(struct vm_area_struct *vma, > pteval = cmpxchg_relaxed(&pte_val(*ptep), old_pteval, pteval); > } while (pteval != old_pteval); > > - flush_tlb_fix_spurious_fault(vma, address); > + /* Invalidate a stale read-only entry */ > + if (dirty) > + flush_tlb_page(vma, address); > return 1; In my proposal I had a pte_accessible(pte) check instead of dirty here since we may go for an old pte directly to a writable one and a TLBI wouldn't be needed. Not that it matters from a performance perspective. Either way, Reviewed-by: Catalin Marinas _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel