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=-14.4 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,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 1CA50C433B4 for ; Mon, 10 May 2021 14:49:41 +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 C1E36613EE for ; Mon, 10 May 2021 14:49:40 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C1E36613EE 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:References:Message-ID: Subject:Cc: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=DqDNydx9957k7OCQ7cSsQACU6OH5QJ5K6sIWT2hPPrY=; b=Qwxm8KPqpGytk2suwdPMeg9PN 8zrzYd9ntf2QH3oaI5LjoJ5TpphZY1ws5X1sj9pCd9KsM6XA/I/U827WEwaKzqNpxWe/npyTw0rJG K378URUyZOGYUW7AcJespn+QbTJjbSZPO6jUox6Iin+0UG8e20ndyrk8iVw0kX77elCDA9+jRCUXK x9IYYb3HFF0NXQkPpvAc8HFePudYrtD76JiwErg2IiW+HHI+6gifuue6lqJtJzOPXF5xO+lWqX/f3 omeiUgW1iRF7bLCNLpl/p/HGsUEJOy5TbCzO90F67cCEu5JD+OaGcS3RkPtG4XA7J4XV0bwWrH5LF dJ3Q34fCA==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lg7CM-00Efxo-Ja; Mon, 10 May 2021 14:47:54 +0000 Received: from bombadil.infradead.org ([2607:7c80:54:e::133]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lg7C0-00Efsp-K5 for linux-arm-kernel@desiato.infradead.org; Mon, 10 May 2021 14:47:32 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=9fedYowOHxwy2rAIvZkQxtfuXOOoe3xzhRceptB4eXU=; b=FieOUVE/Ir1Amw/NZDKkoeFzkZ vHY8PXkocbCaJ1UanuNP9ub2OYFrNIbIkofwAEgbe2WGbDmq06gRw4+yOorpMEb2zIqbdu2QXoq9J fysRrmkzFkYi5c/VWuq+896qKHtFNx3YcVkvJ0hQq6cUHUA/t//a+VTdDT2AQndMFFzBKi3mHbrrv HmRW79TsStIwKXnoOiTZgpXk/croI8vZtCEnh9zAgaIfDwT+9Y3tiuXvnQ3pI4iU078tqmkkM87iW latQ19cRhGF7IhEvybIo0iEcvauftPMcv8DBupoIBQStHchm2MYeJ6MQTbro2rAY4f85A4ILe0GFp pbxBBsyA==; Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lg7Bx-008pJ8-Ob for linux-arm-kernel@lists.infradead.org; Mon, 10 May 2021 14:47:31 +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 4A4B931B; Mon, 10 May 2021 07:47:25 -0700 (PDT) Received: from C02TD0UTHF1T.local (unknown [10.57.4.9]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CE3583F719; Mon, 10 May 2021 07:47:23 -0700 (PDT) Date: Mon, 10 May 2021 15:43:37 +0100 From: Mark Rutland To: Anshuman Khandual Cc: linux-arm-kernel@lists.infradead.org, Catalin Marinas , Will Deacon , linux-kernel@vger.kernel.org Subject: Re: [PATCH] arm64/mm: Remove [PUD|PMD]_TABLE_BIT from [pud|pmd]_bad() Message-ID: <20210510144337.GA92897@C02TD0UTHF1T.local> References: <1620644871-26280-1-git-send-email-anshuman.khandual@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1620644871-26280-1-git-send-email-anshuman.khandual@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210510_074729_865662_AD6B3544 X-CRM114-Status: GOOD ( 19.13 ) 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 Mon, May 10, 2021 at 04:37:51PM +0530, Anshuman Khandual wrote: > Semantics wise, [pud|pmd]_bad() have always implied that a given [PUD|PMD] > entry does not have a pointer to the next level page table. This had been > made clear in the commit a1c76574f345 ("arm64: mm: use *_sect to check for > section maps"). Hence explicitly check for a table entry rather than just > testing a single bit. This basically redefines [pud|pmd]_bad() in terms of > [pud|pmd]_table() making the semantics clear. > > Cc: Catalin Marinas > Cc: Will Deacon > Cc: Mark Rutland > Cc: linux-arm-kernel@lists.infradead.org > Cc: linux-kernel@vger.kernel.org > Signed-off-by: Anshuman Khandual I have no strong feelings either way, so: Acked-by: Mark Rutland ... that said, I think that the "bad" naming is unclear and misleading, and it'd be really nice if we could clean that up treewide with something clearer than "bad". It does seem that would roughly fit p??_leaf() if we had p??_clear_leaf() and p??_none_or_clear_leaf() helpers. Thanks, Mark. > --- > This applies on v5.13-rc1. > > arch/arm64/include/asm/pgtable.h | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h > index 25f5c04b43ce..69f8183bef29 100644 > --- a/arch/arm64/include/asm/pgtable.h > +++ b/arch/arm64/include/asm/pgtable.h > @@ -509,13 +509,12 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, > > #define pmd_none(pmd) (!pmd_val(pmd)) > > -#define pmd_bad(pmd) (!(pmd_val(pmd) & PMD_TABLE_BIT)) > - > #define pmd_table(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \ > PMD_TYPE_TABLE) > #define pmd_sect(pmd) ((pmd_val(pmd) & PMD_TYPE_MASK) == \ > PMD_TYPE_SECT) > #define pmd_leaf(pmd) pmd_sect(pmd) > +#define pmd_bad(pmd) (!pmd_table(pmd)) > > #define pmd_leaf_size(pmd) (pmd_cont(pmd) ? CONT_PMD_SIZE : PMD_SIZE) > #define pte_leaf_size(pte) (pte_cont(pte) ? CONT_PTE_SIZE : PAGE_SIZE) > @@ -602,7 +601,7 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd) > pr_err("%s:%d: bad pmd %016llx.\n", __FILE__, __LINE__, pmd_val(e)) > > #define pud_none(pud) (!pud_val(pud)) > -#define pud_bad(pud) (!(pud_val(pud) & PUD_TABLE_BIT)) > +#define pud_bad(pud) (!pud_table(pud)) > #define pud_present(pud) pte_present(pud_pte(pud)) > #define pud_leaf(pud) pud_sect(pud) > #define pud_valid(pud) pte_valid(pud_pte(pud)) > -- > 2.20.1 > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel