From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6F3224F5DF0 for ; Fri, 18 Sep 2026 13:22:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789737727; cv=none; b=jYCA6gpAOdFniU36bXkm0k+OEAwvWqSudCDhumSTbnzl5aOHRT9/XXHSqcfRpFNP5kJx50paMEAKKDuiUC5Ip3HekBYLxfEqAJm0YxdS/KKLphvdM4CIoY4tW/PFz+XV/C332rfI25X1Nm8xnjLiDWMx9qRI/7MGdjci5YgzygY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789737727; c=relaxed/simple; bh=c2uAbp6cDyt7XZIt8IFdFpXqokCdCrRh4t91+4CD4zw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=rO02tX4eiPBDldE8/bkVRQt4B4Tn0r1dGi6KSIHiaS6B9m7T0MB0lxV/qnLhFjxf4rE1w27sD0AvTmr037qybMKycaR8jGR4LFNHG2XnQtpG8m9hCqujRoQsXypRjjk8MZuUCCPLz7dme3zznDZs3iv9JFVYHyFdYb9NLLMaUR4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=aUjS4QLU; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="aUjS4QLU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 489711F000FF; Fri, 18 Sep 2026 13:22:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789737725; bh=JXII+Q4kZ59ziwT+f57cW04XNzn9YSEFXSVEdQXYv8E=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=aUjS4QLU04DUHHmNztLdm95g6DWY7n8ihJMtYkMjWMJ/ZRGha9aL3TXwk2bTkp1wM zRr5g/TzqAPfdwIYoJdjC3oCCIvW3L1yV8K3Oa929JgHjUtjMsPVoOt8MR03KDQ3fU mRuhOi1x2NVG0KbnYm11d96z1qPr2j9mo25lKdf7coIXO1V1EBhVlgbwEyl2bu/ePG LpUq6pyVlF+LGbWu+XFNzCtMvQapYhlJrNA0WMlBmUKKRymo+bWMMVn2WPEAwIpSIF OyNdZBs+USGUULCcAyQbb+8My0kPtU//nwYIDQCAcMKH5SCBQS1jVYlfjkZVziVik+ hHuZJJ6gvdhNw== Date: Fri, 18 Sep 2026 14:22:00 +0100 From: "Lorenzo Stoakes (ARM)" To: Anshuman Khandual Cc: linux-mm@kvack.org, Andrew Morton , David Hildenbrand , linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm: Constify arguments in default pxdp_get() Message-ID: References: <20260918064928.793742-1-anshuman.khandual@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260918064928.793742-1-anshuman.khandual@arm.com> On Fri, Sep 18, 2026 at 12:19:28PM +0530, Anshuman Khandual wrote: > Generic MM default pxdp_get() helpers fetch the values contained in pgtable > entries via READ_ONCE() without modifying them. Just make their arguments > explicitly 'const' for some additional protection. > > Cc: Andrew Morton > Cc: David Hildenbrand > Cc: Lorenzo Stoakes > Cc: linux-mm@kvack.org > Cc: linux-kernel@vger.kernel.org > Suggested-by: David Hildenbrand > Signed-off-by: Anshuman Khandual LGTM so: Acked-by: Lorenzo Stoakes (ARM) > --- > This patch applies on v7.2-rc3 and builds on many platforms. Some earlier > discussion could be found here. Platorm implementations for these helpers > could convert into these "const" format later if required. > > https://lore.kernel.org/all/yjqldpl7il6uqfoqrszaopchqthhlffssprmlqjkljvpkbpwkt@zetb5hyvllsl/ > > include/linux/pgtable.h | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h > index 2981e386da7b3..f09a91ff5833b 100644 > --- a/include/linux/pgtable.h > +++ b/include/linux/pgtable.h > @@ -490,35 +490,35 @@ static inline int pudp_set_access_flags(struct vm_area_struct *vma, > #endif > > #ifndef ptep_get > -static inline pte_t ptep_get(pte_t *ptep) > +static inline pte_t ptep_get(const pte_t *ptep) > { > return READ_ONCE(*ptep); > } > #endif > > #ifndef pmdp_get > -static inline pmd_t pmdp_get(pmd_t *pmdp) > +static inline pmd_t pmdp_get(const pmd_t *pmdp) > { > return READ_ONCE(*pmdp); > } > #endif > > #ifndef pudp_get > -static inline pud_t pudp_get(pud_t *pudp) > +static inline pud_t pudp_get(const pud_t *pudp) > { > return READ_ONCE(*pudp); > } > #endif > > #ifndef p4dp_get > -static inline p4d_t p4dp_get(p4d_t *p4dp) > +static inline p4d_t p4dp_get(const p4d_t *p4dp) > { > return READ_ONCE(*p4dp); > } > #endif > > #ifndef pgdp_get > -static inline pgd_t pgdp_get(pgd_t *pgdp) > +static inline pgd_t pgdp_get(const pgd_t *pgdp) > { > return READ_ONCE(*pgdp); > } > -- > 2.43.0 > -- Cheers, Lorenzo