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 D121DC54FB9 for ; Wed, 15 Nov 2023 16:39:58 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 53BA96B03A0; Wed, 15 Nov 2023 11:39:58 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 4C43A6B03A2; Wed, 15 Nov 2023 11:39:58 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 33D996B03A3; Wed, 15 Nov 2023 11:39:58 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 2067E6B03A0 for ; Wed, 15 Nov 2023 11:39:58 -0500 (EST) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id E8315C029F for ; Wed, 15 Nov 2023 16:39:57 +0000 (UTC) X-FDA: 81460750434.09.F8D8177 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by imf17.hostedemail.com (Postfix) with ESMTP id 202A540009 for ; Wed, 15 Nov 2023 16:39:55 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=AO9vI+4f; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf17.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=1700066396; 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=HCpNMTIKyOeROsc7/RWOAvMZhqSI0z3duXfnje8m3KQ=; b=q/OxIygfr8+gnoSWE7wD1W4SqYB9NCG54Z7PSe+S6XCF2SMiza4D6uXQ+ydbhdyy4NRgxS gdIOvr2F6339LVUu+dGkRMrpDKmzL4fdfkrR0igZoSQLuDOT/US3uXynViQlyU1X1MxYR+ Zmj4eqAkiy11hwPO36/ITH/PfKIqDJo= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=AO9vI+4f; dmarc=pass (policy=none) header.from=redhat.com; spf=pass (imf17.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=1700066396; a=rsa-sha256; cv=none; b=Mw9F2xrR4Lo0ETSxKobWnjT2YQ9ySkirsgC7U+U+xmIm/F5SUgZ+qAsPmShajbqkU98SU+ lgWCLCXWEaMlilO6AoNDXaBPls+pbtYQaKNj8ZoT7Qq+259joEY3lP5BLLcRTPBHY27jWx 69tBZccEg6AfDIa+PBiYnuxcIJpPM9I= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1700066395; 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=HCpNMTIKyOeROsc7/RWOAvMZhqSI0z3duXfnje8m3KQ=; b=AO9vI+4fQpt3q9v8Oy1jtTZjOUeXANa6DFbj3uS80cYs/SPzv6KkVZfmGtJkQTQyuCEYje M0EZkI8gj7yWBVzAUB9kobQJaUTalRe99NKVbNQ8c9EmQci6NnZR3ufwwTdxpNNnrerFfC iPdsxc/efrV9s1Y/MdFpJTVtXLAUFkY= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-121-UdDnholkMuG4DRRASuNUrQ-1; Wed, 15 Nov 2023 11:39:50 -0500 X-MC-Unique: UdDnholkMuG4DRRASuNUrQ-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E6F20101B04B; Wed, 15 Nov 2023 16:39:46 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.42.28.16]) by smtp.corp.redhat.com (Postfix) with ESMTP id F0B85492BE8; Wed, 15 Nov 2023 16:39:33 +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: <20231115154946.3933808-1-dhowells@redhat.com> <20231115154946.3933808-6-dhowells@redhat.com> To: Linus Torvalds Cc: dhowells@redhat.com, Christian Brauner , Jens Axboe , Al Viro , Christoph Hellwig , David Laight , Matthew Wilcox , Brendan Higgins , David Gow , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, kunit-dev@googlegroups.com, linux-kernel@vger.kernel.org, Andrew Morton , Christian Brauner , David Hildenbrand , John Hubbard , Huacai Chen , WANG Xuerui , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , loongarch@lists.linux.dev, linux-s390@vger.kernel.org Subject: Re: [PATCH v3 05/10] iov_iter: Create a function to prepare userspace VM for UBUF/IOVEC tests MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <3936725.1700066370.1@warthog.procyon.org.uk> Date: Wed, 15 Nov 2023 16:39:30 +0000 Message-ID: <3936726.1700066370@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.9 X-Rspamd-Queue-Id: 202A540009 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: kryhf31wtqs1oyt9aewgtsijr6c449h6 X-HE-Tag: 1700066395-491192 X-HE-Meta: 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 SbVdqFuw zU4dwCMJ98Z2LC+F5f9nTPfVi+PfWztsKZZ9JFmBixSkW9rZ1ENPt0VEx10AIk8pkSYNcYv50KqPLvOTwGDgRPsc5xS3w2lgk+B3HvkX7cWHcKlEY5A2gJZa04u3zQ7DxVsY7OU31JB5PNhtwTqfa1F/Tge1rCL4Hvg5S+zBCZKf5Eyu63c4k7RTZoDes+9MmDfhR/25Wt6i58F2lVk3hR2nCUwDbOwhGu8E0MNNI0mn/Cqsa84yZLK0tWT2q/hcLrE1VveNd0BdDXT15vYOLNFoNUm2/aK/BAVZG/ny/RQMWILRwA4sbZPOHQsi6HXrkiZ+mWounrw6SnnHAukkBJCEXZyhrK5QggAoF 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: List-Subscribe: List-Unsubscribe: Linus Torvalds wrote: > From a quick look, what you were doing was checking that the patterns > you set up in user space came through ok. Dammit, what's wrong with > just using read()/write() on a pipe, or splice, or whatever. It will > test exactly the same iov_iter thing. I was trying to make it possible to do these tests before starting userspace as there's a good chance that if the UBUF/IOVEC iterators don't work right then your system can't be booted. Anyway, if I drop patches 5, 6, 7 and 10 (ie. the ones doing stuff with UBUF and IOVEC-type iterators), would you be okay with the rest? David