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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id C2BA4EB64D7 for ; Wed, 28 Jun 2023 19:18:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 413E38D0006; Wed, 28 Jun 2023 15:18:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3C2AA8D0001; Wed, 28 Jun 2023 15:18:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 28B088D0006; Wed, 28 Jun 2023 15:18:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 176CF8D0001 for ; Wed, 28 Jun 2023 15:18:39 -0400 (EDT) Received: from smtpin21.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id E37ED1C802D for ; Wed, 28 Jun 2023 19:18:38 +0000 (UTC) X-FDA: 80953118316.21.6A8F949 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf09.hostedemail.com (Postfix) with ESMTP id C76D214001E for ; Wed, 28 Jun 2023 19:18:36 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=bPQzwSoB; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf09.hostedemail.com: domain of dhowells@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=dhowells@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1687979916; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=z3+WfKV5Wz85M3f84YrJfAbIjSPqDA0LNe6BQbP5oxI=; b=KfSpbIBilgwY6+ALeW9HPS6QnhsuCjehbE2/NCnY4LYfLIUu15SxRfVgairgt7ZpgVtuNE aZiMrEZOlXUeYSKDq2F14ftbzr3dGF4EXa+pm6QrCWgs32qkfIyi3ad68X0cZolbLnBbx9 ypPzL5eupuB3U09ad8CPbznMX2CmIsQ= ARC-Authentication-Results: i=1; imf09.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=bPQzwSoB; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf09.hostedemail.com: domain of dhowells@redhat.com designates 170.10.129.124 as permitted sender) smtp.mailfrom=dhowells@redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1687979916; a=rsa-sha256; cv=none; b=eIcR2O5Vmg77Pek288V/CWHCuvnBUO5OfituPP6mhAEwFYsS/8ypoyowszOcrr9JjhTbVy DwprM58RU+VRb2QsGkYYcbGANVvDjz6nB0jJ0SR/a3Tx1Cx11Bilfo/xlI0X+/9QQ6NV47 SioaV83Bggid8Iixed+qrbX6qnu085A= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1687979915; 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=z3+WfKV5Wz85M3f84YrJfAbIjSPqDA0LNe6BQbP5oxI=; b=bPQzwSoBvfJo73uJa/cM9K2dYptd1vJMixS9Ar5VM8mPPSsoMkkeV4bLU3lFeHij1Pdmru X2HK5xRkXYiKYYbP8AVYj2RybO86ikUoSv26L1qBp/9viHA1BTTXSUGdjMPWVwUPu6kxva s5xgvHdudZStD8upiMAADDKGRrkWkWE= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-401-x-1JRoffOwuUYVdkw7tiHQ-1; Wed, 28 Jun 2023 15:18:34 -0400 X-MC-Unique: x-1JRoffOwuUYVdkw7tiHQ-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 5A56F185A7A4; Wed, 28 Jun 2023 19:18:33 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.42.28.4]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8F7FF46EE28; Wed, 28 Jun 2023 19:18:32 +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: <20230626085035.e66992e96b4c6d37dad54bd9@linux-foundation.org> To: Linus Torvalds Cc: dhowells@redhat.com, Andrew Morton , Stephen Rothwell , linux-mm@kvack.org, mm-commits@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [GIT PULL] MM updates for 6.5-rc1 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <3696803.1687979912.1@warthog.procyon.org.uk> Date: Wed, 28 Jun 2023 20:18:32 +0100 Message-ID: <3696804.1687979912@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: C76D214001E X-Stat-Signature: aofp5kzbay78kh79kpe6pjistyo4upj6 X-HE-Tag: 1687979916-369495 X-HE-Meta: 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 5LtpHnSM v85UJwv1/GxmdAZjbdr9SSyJdfMRJhSnj40oJFFShnX0eGkooruKfFwMuN7MTqOAFfd2jgHdT7LkI2AFcztEO1njo4AfQAS8oqGYLkyHl5yQPO0mSmiBibmctpzWkr2hnZOi8nr6bSZ58RWNMxYW0hnV73k63d/swCy7ys07PJ5Vxchgmw6Jizwppo79QoCQIYCxDRJlNu/r4sR7LMbaKNIQCwA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Linus Torvalds wrote: > Side note: I think we should just do the "FOLL_GET" doesn't touch the > refcount either, which would make this all become just Yeah... but there's a lot of places that would potentially need fixing. iov_iter_get_pages*(), for example, is used to grab pages and push them to all sorts of destinations, including pipes and sk_buffs. > but then we would need to fix try_grab_page() and gup_put_folio() and > friends to match. And any other cases I haven't thought of. And put_page(), folio_put(), ... I wonder if there would be a noticeable performance loss from adding an is_zero_page() check into those. It might also make sense to include the entire kernel post-init static image in that, perhaps a check: if ((unsigned long)(virt_address) & KERNEL_MASK == KERNEL_BASE) return; David