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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5DAFBF483CC for ; Mon, 23 Mar 2026 16:29:08 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1w4i8w-0002Hm-Dw; Mon, 23 Mar 2026 12:28:42 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1w4i8v-0002HG-1H for qemu-devel@nongnu.org; Mon, 23 Mar 2026 12:28:41 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1w4i8t-0002za-BC for qemu-devel@nongnu.org; Mon, 23 Mar 2026 12:28:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1774283316; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BzLbeZzxLSzxpQn7b8CzgnTGIhEcqDdeUipL8JUjw6k=; b=OyaSojr9XSJO9g/SnRm3z0eUJbtqPuXmFFc1e5zSkLlNWkuiz2XYlnutxl0pC6zVZQjMH+ x1bJYROgnva+DCIJhxz2oR6ltiJeXUqJZt106SotpXlZjONFyXljt9BGqFYfFCNeaybGPT lNog3OWYZXMHeXions3JX9BLiWGt/oQ= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-391-iErOObFVM3OOaqc62ISY2w-1; Mon, 23 Mar 2026 12:28:35 -0400 X-MC-Unique: iErOObFVM3OOaqc62ISY2w-1 X-Mimecast-MFC-AGG-ID: iErOObFVM3OOaqc62ISY2w_1774283314 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (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 mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 4751A18005BA; Mon, 23 Mar 2026 16:28:34 +0000 (UTC) Received: from redhat.com (unknown [10.45.225.184]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 4B1881800764; Mon, 23 Mar 2026 16:28:32 +0000 (UTC) Date: Mon, 23 Mar 2026 17:28:30 +0100 From: Kevin Wolf To: Hanna Czenczek Cc: qemu-block@nongnu.org, qemu-devel@nongnu.org, Aarushi Mehta , Stefan Hajnoczi , Stefano Garzarella Subject: Re: [PATCH for-11.0 0/3] linux-aio/io-uring: Resubmit tails of short requests Message-ID: References: <20260318153206.171494-1-hreitz@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260318153206.171494-1-hreitz@redhat.com> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Received-SPF: pass client-ip=170.10.129.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Am 18.03.2026 um 16:32 hat Hanna Czenczek geschrieben: > Hi, > > Short reads and writes can happen. One way to reproduce them is via > FUSE export, if you force it to limit the request length in the > read/write path (patch in the commit messages of patches 2 and 3), but > specifically short writes apparently can also happen with NFS. > > For the file-posix block driver, aio=threads already takes care of them. > aio=native does not, at all, and aio=io_uring only handles short reads, > but not writes. This series has both aio=native and aio=io_uring handle > both short reads and writes. zone-append is not touched, as I don’t > believe resubmitting the tail (if a short append can even happen) is > safe. Originally, I think you had intended to loop in coroutine code. Now it looks like you decided to resubmit already on the lower level directly when processing completions. Obviously, both approaches work, but I'm curious what are the reasons that made you pick this approach after all. Kevin