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 lists1p.gnu.org (lists1p.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 94931CC6B1A for ; Tue, 13 Oct 2026 18:54:59 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1xGhdW-00021c-OD; Tue, 13 Oct 2026 14:54:06 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1xGhdR-000215-Id for qemu-devel@nongnu.org; Tue, 13 Oct 2026 14:54:02 -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 1xGhdP-0004bu-SC for qemu-devel@nongnu.org; Tue, 13 Oct 2026 14:54:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1791917638; 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=HehFh7OkvbsTgK+YqQfAJ08j57XDRenW466lQbknDB0=; b=JKTHtTOcJhsnB7X0u/0yRrYscNAvew6YMya6nVUTOKbHqeOv6X/5hNRbO/NUFbDWPnB6fZ hVZnHH4C2F3Lgbbv4yhJM9QGLhMIL7r/3kgpdMEgUP9GHmPyVVHthrU2zJyG7EKTv71qD1 jwsFrhu8e3TVowvnwXhmoTf7RrUe7hs= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-191-P6-XHFggO9WIl8b66vltYA-1; Tue, 13 Oct 2026 18:53:56 +0000 X-MC-Unique: P6-XHFggO9WIl8b66vltYA-1 X-Mimecast-MFC-AGG-ID: P6-XHFggO9WIl8b66vltYA_1791917635 Received: from mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.95]) (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-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 8DA48195FDF8; Tue, 13 Oct 2026 18:53:55 +0000 (UTC) Received: from redhat.com (headnet04.pony-001.prod.iad2.dc.redhat.com [10.2.32.116]) by mx-prod-int-10.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id A1EE976B; Tue, 13 Oct 2026 18:53:53 +0000 (UTC) Date: Tue, 13 Oct 2026 13:53:51 -0500 From: Eric Blake To: Ilya Leoshkevich Cc: Kevin Wolf , Hanna Reitz , qemu-block@nongnu.org, qemu-devel@nongnu.org Subject: Re: [PATCH] iotests/108: probe loop device setup Message-ID: References: <20261013182804.103882-1-iii@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261013182804.103882-1-iii@linux.ibm.com> User-Agent: NeoMutt/20260616 X-Scanned-By: MIMEDefang 3.6 on 10.30.177.95 Received-SPF: pass client-ip=170.10.129.124; envelope-from=eblake@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: 10 X-Spam_score: 1.0 X-Spam_bar: + X-Spam_report: (1.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.24, 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_SBL_CSS=3.335, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no 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 On Tue, Oct 13, 2026 at 08:28:00PM +0200, Ilya Leoshkevich wrote: > Running iotests/108 in a Docker container, that has passwordless sudo > configured, fails with: > > losetup: /home/user/src/qemu/build/scratch/qcow2-file-108/t.qcow2: failed to set up loop device: No such file or directory > > because it incorrectly assumes losetup is allowed to do loop device > setup, when in reality it can only list devices. > > Fix by probing loop device setup, using the test script as a backing > file. With this, the test is correctly skipped. > > Signed-off-by: Ilya Leoshkevich > --- > tests/qemu-iotests/108 | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/tests/qemu-iotests/108 b/tests/qemu-iotests/108 > index 1de718188aa..adbaaf87095 100755 > --- a/tests/qemu-iotests/108 > +++ b/tests/qemu-iotests/108 > @@ -53,7 +53,8 @@ _supported_os Linux > _unsupported_imgopts 'refcount_bits=\([^1]\|.\([^6]\|$\)\)' data_file > > # This test either needs sudo -n losetup or FUSE exports to work > -if sudo -n losetup &>/dev/null; then > +if probe_dev=$(sudo -n losetup -r --show -f "$0" 2>/dev/null); then > + sudo -n losetup -d "$probe_dev" Is 'sudo -n losetup -f' a simpler test? It prints out the next /dev/loopN value available only if a mount would succeed, which means that it is a stronger test than the existing 'sudo -n losetup', but also does not require a subsequent cleanup. -- Eric Blake, Principal Software Engineer Red Hat, Inc. 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