Re: [libvirt] [PATCH 0/2] qemu: Rework CD/DVD changing

On 05/17/2013 04:07 PM, Michal Privoznik wrote: > On 17.05.2013 07:47, Li Wei wrote: >> Hi Michal, Daniel >> >> It seems there is something wrong with the 2/2 part of this patchset. >> When I do an "change-media" command in virsh, it doesn't do any better >> than before, but even worse(I must to wait 5 secs to see the error). >> >> I'm not family with libvirt, just add some log things in the qemu_hotplug.c >> and found the tray_status never change to open, but with michal's original >> patch (which do active poll on tray_status), I can do "change-media" successfully >> every time. > > Yes & no. Thing is - originally we ignored tray status in the guest. So > in case guest has locked the tray and thus ignored our eject request, we > have changed the media anyway, resulting in possible I/O errors within > guest. > > With my patch, we send eject request to the qemu, and actively poll for > the tray to open. We check for up to 10 times every 200ms. So guest has > 2 seconds to open the tray. If the guest doesn't eject media and open > the tray we don't proceed with forcibly changing the media. > > These patches are actually a bug fix for > https://bugzilla.redhat.com/show_bug.cgi?id=892289 Hmm... I think you misunderstood my meaning(sorry for my pool english), simply to say, I can get expected behavior by apply patch V1 but not V2. In V1, we do active poll on qemuMonitorGetBlockInfo(), and in V2 we just wait for origdisk->tray_status to become VIR_DOMAIN_DISK_TRAY_OPEN but this never happened. Thanks, Wei

> >> >> IMHO, there must be some bug in the processing of qemu tray change. >> >> Thanks, >> Wei >> >> >> On 01/25/2013 08:20 PM, Michal Privoznik wrote: >>> The first patch is bare bug fix (without any bug reported though). >>> The second is again a bug fix, but not so easy to spot. Basically, when we >>> change a media, we should issue 'eject' first, then wait until the tray gets >>> open, after which we can finally issue 'change' command. Even for bare 'eject' >>> we ought to check status, shouldn't we? >>> >>> Michal Privoznik (2): >>> qemu_monitor: Fix tray-open attribute in query-block >>> qemu_hotplug: Rework media changing process >>> >>> src/qemu/qemu_hotplug.c | 51 +++++++++++++++++++++++++++++++++++++++++--- >>> src/qemu/qemu_monitor_json.c | 2 +- >>> src/qemu/qemu_monitor_text.c | 6 +++--- >>> 3 files changed, 52 insertions(+), 7 deletions(-) >>> > > -- libvir-list mailing list libvir-list(a)redhat.com https://www.redhat.com/mailman/listinfo/libvir-list