[pve-devel] [PATCH 1/2] enable virtio-scsi iothread hot-unplug

[Alexandre DERUMIER]

>>The hot-remove seems to error out (while it still works in the
>>background and after doing a 'revert' and a second 'remove' it finishes
>>successfully.)

>>But adding the device back into the same slot as before crashes qemu,
>>whereas a pure hot-add with no removal before works fine.

Ok, so it's not 100% safe yet. Better to try again with qemu 2.7.

Thanks for testing !


----- Mail original -----
De: "Wolfgang Bumiller" <w.bumiller at proxmox.com>
À: "aderumier" <aderumier at odiso.com>
Cc: "pve-devel" <pve-devel at pve.proxmox.com>
Envoyé: Lundi 22 Août 2016 11:21:19
Objet: Re: [pve-devel] [PATCH 1/2] enable virtio-scsi iothread hot-unplug

The hot-remove seems to error out (while it still works in the 
background and after doing a 'revert' and a second 'remove' it finishes 
successfully.) 

But adding the device back into the same slot as before crashes qemu, 
whereas a pure hot-add with no removal before works fine. 

On Sat, Aug 20, 2016 at 10:02:28AM +0200, Alexandre Derumier wrote: 
> This was previously buggy in qemu 2.3 (crash the vm), 
> now it's working fine in qemu 2.6 
> 
> Signed-off-by: Alexandre Derumier <aderumier at odiso.com> 
> --- 
> PVE/QemuServer.pm | 9 ++++----- 
> 1 file changed, 4 insertions(+), 5 deletions(-) 
> 
> diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm 
> index 2414fd8..b295ae4 100644 
> --- a/PVE/QemuServer.pm 
> +++ b/PVE/QemuServer.pm 
> @@ -3401,10 +3401,6 @@ sub vm_deviceunplug { 
> 
> } elsif ($deviceid =~ m/^(scsi)(\d+)$/) { 
> 
> - #qemu 2.3 segfault on drive_del with virtioscsi + iothread 
> - my $device = parse_drive($deviceid, $conf->{$deviceid}); 
> - die "virtioscsi with iothread is not hot-unplugglable currently" if $device->{iothread}; 
> - 
> qemu_devicedel($vmid, $deviceid); 
> qemu_drivedel($vmid, $deviceid); 
> qemu_deletescsihw($conf, $vmid, $deviceid); 
> @@ -3449,7 +3445,10 @@ sub qemu_iothread_add { 
> sub qemu_iothread_del { 
> my($conf, $vmid, $deviceid) = @_; 
> 
> - my $device = parse_drive($deviceid, $conf->{$deviceid}); 
> + my $drive = $deviceid; 
> + $drive =~ s/virtioscsi/scsi/; 
> + my $device = parse_drive($drive, $conf->{$drive}); 
> + 
> if ($device->{iothread}) { 
> my $iothreads = vm_iothreads_list($vmid); 
> qemu_objectdel($vmid, "iothread-$deviceid") if $iothreads->{"iothread-$deviceid"}; 
> -- 
> 2.1.4