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 X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8E73BC433E2 for ; Mon, 31 Aug 2020 11:21:18 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 5D4F9207DA for ; Mon, 31 Aug 2020 11:21:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5D4F9207DA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bugs.launchpad.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:45056 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kChsD-0005an-KQ for qemu-devel@archiver.kernel.org; Mon, 31 Aug 2020 07:21:17 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:51340) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kChrh-0005Af-Qs for qemu-devel@nongnu.org; Mon, 31 Aug 2020 07:20:45 -0400 Received: from indium.canonical.com ([91.189.90.7]:51302) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1kChrf-0002OO-Mu for qemu-devel@nongnu.org; Mon, 31 Aug 2020 07:20:45 -0400 Received: from loganberry.canonical.com ([91.189.90.37]) by indium.canonical.com with esmtp (Exim 4.86_2 #2 (Debian)) id 1kChrd-0007kT-Qw for ; Mon, 31 Aug 2020 11:20:41 +0000 Received: from loganberry.canonical.com (localhost [127.0.0.1]) by loganberry.canonical.com (Postfix) with ESMTP id C63792E80DB for ; Mon, 31 Aug 2020 11:20:41 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Date: Mon, 31 Aug 2020 11:08:29 -0000 From: Tom Yan <1893634@bugs.launchpad.net> To: qemu-devel@nongnu.org X-Launchpad-Notification-Type: bug X-Launchpad-Bug: product=qemu; status=New; importance=Undecided; assignee=None; X-Launchpad-Bug-Information-Type: Public X-Launchpad-Bug-Private: no X-Launchpad-Bug-Security-Vulnerability: no X-Launchpad-Bug-Commenters: tom-ty89 X-Launchpad-Bug-Reporter: Tom Yan (tom-ty89) X-Launchpad-Bug-Modifier: Tom Yan (tom-ty89) References: <159886949002.28151.4021199873744523881.malonedeb@soybean.canonical.com> Message-Id: <159887210987.22277.15768282066317792490.launchpad@chaenomeles.canonical.com> Subject: [Bug 1893634] Re: blk_get_max_transfer() works only with sg X-Launchpad-Message-Rationale: Subscriber (QEMU) @qemu-devel-ml X-Launchpad-Message-For: qemu-devel-ml Precedence: bulk X-Generated-By: Launchpad (canonical.com); Revision="195cbfa84cb75815472f69dd83d46f006869050b"; Instance="production" X-Launchpad-Hash: 3a1eb49a7842c3a69474b8315f6b2071240651c5 Received-SPF: none client-ip=91.189.90.7; envelope-from=bounces@canonical.com; helo=indium.canonical.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/08/31 04:40:47 X-ACL-Warn: Detected OS = Linux 3.11 and newer [fuzzy] X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.001, RCVD_IN_DNSWL_HI=-5, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Bug 1893634 <1893634@bugs.launchpad.net> Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" ** Description changed: blk_get_max_transfer() is supposed to be able to get the max_sectors queue limit of the scsi device on the host side and is used in both scsi-generic.c (for scsi-generic and scsi-block) and scsi-disk.c (for scsi-hd) to set/change the max_xfer_len (and opt_xfer_len in the case of - scsi-generic). + scsi-generic.c). = However, it only works with the sg driver in doing so. It cannot get the queue limit with the sd driver and simply returns MAX_INT. = qemu version 5.1.0 kernel version 5.8.5 = Btw, is there a particular reason that it doesn't MIN_NON_ZERO against the original max_xfer_len: https://github.com/qemu/qemu/blob/v5.1.0/hw/scsi/scsi-generic.c#L172? -- = You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1893634 Title: blk_get_max_transfer() works only with sg Status in QEMU: New Bug description: blk_get_max_transfer() is supposed to be able to get the max_sectors queue limit of the scsi device on the host side and is used in both scsi-generic.c (for scsi-generic and scsi-block) and scsi-disk.c (for scsi-hd) to set/change the max_xfer_len (and opt_xfer_len in the case of scsi-generic.c). However, it only works with the sg driver in doing so. It cannot get the queue limit with the sd driver and simply returns MAX_INT. qemu version 5.1.0 kernel version 5.8.5 Btw, is there a particular reason that it doesn't MIN_NON_ZERO against the original max_xfer_len: https://github.com/qemu/qemu/blob/v5.1.0/hw/scsi/scsi-generic.c#L172? To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1893634/+subscriptions