From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52662) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eye7F-0005ze-A4 for Qemu-devel@nongnu.org; Wed, 21 Mar 2018 09:49:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eye7C-0006tL-79 for Qemu-devel@nongnu.org; Wed, 21 Mar 2018 09:49:21 -0400 From: Pino Toscano Date: Wed, 21 Mar 2018 14:48:54 +0100 Message-ID: <2075074.dXtERdIzXi@thyrus.usersys.redhat.com> In-Reply-To: <65a7365f-89d5-a66c-4e7a-ce8ae1bcf595@redhat.com> References: <20180321124417.29242-1-ptoscano@redhat.com> <20180321125105.GJ19514@redhat.com> <65a7365f-89d5-a66c-4e7a-ce8ae1bcf595@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart2077856.cQrCGbDHyq"; micalg="pgp-sha256"; protocol="application/pgp-signature" Subject: Re: [Qemu-devel] [Libguestfs] [PATCH] tests: regressions: make test-big-heap use a temporary empty file List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: libguestfs@redhat.com Cc: Eric Blake , "Richard W.M. Jones" , qemu block , "Qemu-devel@nongnu.org" --nextPart2077856.cQrCGbDHyq Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" On Wednesday, 21 March 2018 14:45:38 CET Eric Blake wrote: > [adding qemu lists] > > On 03/21/2018 07:51 AM, Richard W.M. Jones wrote: > > On Wed, Mar 21, 2018 at 01:44:17PM +0100, Pino Toscano wrote: > >> Newer versions of qemu use file locking for the images by default, and > >> apparently that does not work with /dev/null. Since this test just > >> calls qemu-img to get the format of an empty image, create a temporary > >> one instead. > > > > ACK, but feels like this is a bug in qemu-img to me. > > You're right that file locking on a character device like /dev/null is > not going to work as expected, but is it a case where fcntl() actually > fails, or is it worse where the fcntl() claiming the locks "succeeds" > but doesn't do what we want? That is, what were the actual error > messages you ran into? $ qemu-img --version qemu-img version 2.10.1(qemu-2.10.1-2.fc27) Copyright (c) 2003-2017 Fabrice Bellard and the QEMU Project developers $ qemu-img info /dev/null qemu-img: Could not open '/dev/null': Failed to get "consistent read" lock Is another process using the image? -- Pino Toscano --nextPart2077856.cQrCGbDHyq Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part. Content-Transfer-Encoding: 7Bit -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEbjdOQa52nq0tQalew9FMLZhkN80FAlqyYsYACgkQw9FMLZhk N81v6A/+ItfARU/N5BjeoBm4LZA4BnH02bvFCS1xYKyx21ul1dmx5UMnVfK4wBKf z1Tbas69ZHbYnGbjkLUuai3vBgKrKOKWcWvgMZXMxTnzCgtxG34hJCTxwQj6EZZ7 PLO/dAGkpuwiU4H9Jok9PJCSw1m3dIABwhbvXzLSakUAVanvf3f64MaLbd+/lWYB Jp+DhRf31WagPxLuvE3oZrKvUnvTFSuAWNGc6bymn7BTjdIrDoLfFME3NNmDy/bX 1ZnPtOGxhP0O0LHimec7e7bi7nc61ga6Wo1lcDqw6ZB+I/fwPzqziGICT5mWqdv4 fNduDwFEk0xnRvH8wZbHp/3rQx8/s/GPHCMmBZS6OSJm55kM1ltbGmfdcWvGYiDe ZFnAXbapzPr6QbXHWXGZIkSWsmYny/GmFtXSa7mh/Vqqj9QiPV9HyPa+ESN5YPcE wxV68XdJ+9Jhich0Wbjjbx+wgKj+iTzHTuABYg0nwAY8na10DDqXefGcKjmZRE23 B7Hh4ZE8wTwd5Fhp5Mrd8LIQ9C7yRpqC7xVPDH63weBambyHT8Jby642By7kSMQ+ 0jE1JT0+/xey1BHiwfqQs20sYUtq+q+RTc12IrxJDXCT99/u5qSaJARKKCLKgoGm GnwCBRKsSylWP/zlVGb/I+5iygBqZ1kUwWL1sJ5043C9W8lDiTQ= =cnFh -----END PGP SIGNATURE----- --nextPart2077856.cQrCGbDHyq--