From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:39551) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gpboO-00085C-5L for qemu-devel@nongnu.org; Fri, 01 Feb 2019 11:37:05 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gpboL-0000Iv-LL for qemu-devel@nongnu.org; Fri, 01 Feb 2019 11:37:03 -0500 From: Kevin Wolf Date: Fri, 1 Feb 2019 17:35:17 +0100 Message-Id: <20190201163518.31157-27-kwolf@redhat.com> In-Reply-To: <20190201163518.31157-1-kwolf@redhat.com> References: <20190201163518.31157-1-kwolf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PULL 26/27] scsi-disk: Don't use empty string as device id List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: kwolf@redhat.com, peter.maydell@linaro.org, qemu-devel@nongnu.org scsi-disk includes in the Device Identification VPD page, depending on configuration amongst others, a vendor specific designator that consists either of the serial number if given or the BlockBackend name (which is a host detail that better shouldn't have been leaked to the guest, but now we have to maintain it for compatibility). With anonymous BlockBackends, i.e. scsi-disk devices constructed with drive=3D, and no serial number explicitly specified, this ends up as an empty string. If this happens to more than one disk, we have accidentally signalled to the OS that this is a multipath setup, which is obviously not what was intended. Instead of using an empty string for the vendor specific designator, simply leave out that designator, which makes Linux detect such setups as separate disks again. Signed-off-by: Kevin Wolf Reviewed-by: Eric Blake Reviewed-by: Philippe Mathieu-Daud=C3=A9 --- hw/scsi/scsi-disk.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c index b049026219..11392a8db8 100644 --- a/hw/scsi/scsi-disk.c +++ b/hw/scsi/scsi-disk.c @@ -652,12 +652,14 @@ static int scsi_disk_emulate_vpd_page(SCSIRequest *= req, uint8_t *outbuf) DPRINTF("Inquiry EVPD[Device identification] " "buffer size %zd\n", req->cmd.xfer); =20 - outbuf[buflen++] =3D 0x2; /* ASCII */ - outbuf[buflen++] =3D 0; /* not officially assigned */ - outbuf[buflen++] =3D 0; /* reserved */ - outbuf[buflen++] =3D id_len; /* length of data following */ - memcpy(outbuf + buflen, str, id_len); - buflen +=3D id_len; + if (id_len) { + outbuf[buflen++] =3D 0x2; /* ASCII */ + outbuf[buflen++] =3D 0; /* not officially assigned */ + outbuf[buflen++] =3D 0; /* reserved */ + outbuf[buflen++] =3D id_len; /* length of data following */ + memcpy(outbuf + buflen, str, id_len); + buflen +=3D id_len; + } =20 if (s->qdev.wwn) { outbuf[buflen++] =3D 0x1; /* Binary */ --=20 2.20.1