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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4D83AC77B7A for ; Fri, 26 May 2023 08:30:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236343AbjEZIaS (ORCPT ); Fri, 26 May 2023 04:30:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34732 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242661AbjEZIaL (ORCPT ); Fri, 26 May 2023 04:30:11 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4AC5619C for ; Fri, 26 May 2023 01:29:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1685089769; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=c892gmHnFnyJknfSVBWfjI1O+CRXJGRWy+yybVQO/8A=; b=cFhpiHDKvo2x30cHJRaNGprlQFTAO3McevsP04WM2OfEZqoTAc0i9aD3LH08lgvX+O2vDB 0oygoi+qFsh4WfDggal4J31geI6S76sVDWNqYBLo/CUzhGCNxJzv1sSjEUD6dx4qho6Vir DdeQMiZ/GxHHva9iqa6Y/50qcKnfOh4= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-436-bQLEo4I9MN6xV7hqaz2Y0Q-1; Fri, 26 May 2023 04:29:24 -0400 X-MC-Unique: bQLEo4I9MN6xV7hqaz2Y0Q-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 0A07538035A6; Fri, 26 May 2023 08:29:24 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.39.192.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6C9D19D7A; Fri, 26 May 2023 08:29:20 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: References: <20230525223953.225496-1-dhowells@redhat.com> <20230525223953.225496-2-dhowells@redhat.com> To: Christoph Hellwig Cc: dhowells@redhat.com, David Hildenbrand , Jens Axboe , Al Viro , Matthew Wilcox , Jan Kara , Jeff Layton , Jason Gunthorpe , Logan Gunthorpe , Hillf Danton , Christian Brauner , Linus Torvalds , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton Subject: Re: [RFC PATCH v2 1/3] mm: Don't pin ZERO_PAGE in pin_user_pages() MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <520321.1685089759.1@warthog.procyon.org.uk> Date: Fri, 26 May 2023 09:29:19 +0100 Message-ID: <520322.1685089759@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Christoph Hellwig wrote: > Shouldn't unpin_user_pages It calls gup_put_folio() which is where the skip is. > and bio_release_page also be updated to skip a zero page here? Porbably best to leave it to unpin_user_page() there. I've tried to hide the behaviour entirely within gup.c. David