[pve-devel] Regression with latest qemu and iothreads option ?

[Emmanuel Kasper]

Hi
I am using

kvm --version
QEMU emulator version 2.3.92

I have noticed if you select the iothread option in the disk options of
your KVM, KVM hangs in a very nasty way: the kvm processes starts, the
qm manager reports the machine as running but actually it is not: it is
not possible to attach a qm terminal or qm monitor, or vnc console, it
seems the processes ignores the messages being sent over the qmp socket:


qm config 100 | grep iothread

virtio0: big1:vm-100-disk-1,cache=unsafe,backup=no,iothread=on,size=16G

qm monitor 100
Entering Qemu Monitor for VM 100 - type 'help' for help
qm> info blockdev
ERROR: VM 100 qmp command 'human-monitor-command' failed - unable to
connect to VM 100 qmp socket - timeout after 31 retries


Emmanuel

[Alexandre DERUMIER]

I can reproduce it too, enabling iothread hang qmp. (qemu process don't crash)

I have tested it with qemu 2.4 some weeks ago (before rc0, without any proxmox patches),
and it was working fine.

----- Mail original -----
De: "Emmanuel Kasper" <***@proxmox.com>
À: "pve-devel" <pve-***@pve.proxmox.com>
Envoyé: Mardi 28 Juillet 2015 15:26:07
Objet: [pve-devel] Regression with latest qemu and iothreads option ?

Hi
I am using

kvm --version
QEMU emulator version 2.3.92

I have noticed if you select the iothread option in the disk options of
your KVM, KVM hangs in a very nasty way: the kvm processes starts, the
qm manager reports the machine as running but actually it is not: it is
not possible to attach a qm terminal or qm monitor, or vnc console, it
seems the processes ignores the messages being sent over the qmp socket:


qm config 100 | grep iothread

virtio0: big1:vm-100-disk-1,cache=unsafe,backup=no,iothread=on,size=16G

qm monitor 100
Entering Qemu Monitor for VM 100 - type 'help' for help
qm> info blockdev
ERROR: VM 100 qmp command 'human-monitor-command' failed - unable to
connect to VM 100 qmp socket - timeout after 31 retries


Emmanuel

_______________________________________________
pve-devel mailing list
pve-***@pve.proxmox.com
http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel

[Alexandre DERUMIER]

qemu 2.4rc0 works fine.

I'll try to find the bad commit

----- Mail original -----
De: "aderumier" <***@odiso.com>
À: "Emmanuel Kasper" <***@proxmox.com>
Cc: "pve-devel" <pve-***@pve.proxmox.com>
Envoyé: Mardi 28 Juillet 2015 18:49:56
Objet: Re: [pve-devel] Regression with latest qemu and iothreads option ?

I can reproduce it too, enabling iothread hang qmp. (qemu process don't crash)

I have tested it with qemu 2.4 some weeks ago (before rc0, without any proxmox patches),
and it was working fine.

----- Mail original -----
De: "Emmanuel Kasper" <***@proxmox.com>
À: "pve-devel" <pve-***@pve.proxmox.com>
Envoyé: Mardi 28 Juillet 2015 15:26:07
Objet: [pve-devel] Regression with latest qemu and iothreads option ?

Hi
I am using

kvm --version
QEMU emulator version 2.3.92

I have noticed if you select the iothread option in the disk options of
your KVM, KVM hangs in a very nasty way: the kvm processes starts, the
qm manager reports the machine as running but actually it is not: it is
not possible to attach a qm terminal or qm monitor, or vnc console, it
seems the processes ignores the messages being sent over the qmp socket:


qm config 100 | grep iothread

virtio0: big1:vm-100-disk-1,cache=unsafe,backup=no,iothread=on,size=16G

qm monitor 100
Entering Qemu Monitor for VM 100 - type 'help' for help
qm> info blockdev
ERROR: VM 100 qmp command 'human-monitor-command' failed - unable to
connect to VM 100 qmp socket - timeout after 31 retries


Emmanuel

_______________________________________________
pve-devel mailing list
pve-***@pve.proxmox.com
http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel

_______________________________________________
pve-devel mailing list
pve-***@pve.proxmox.com
http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel

[Alexandre DERUMIER]

qemu 2.4rc1 works fine

qemu 2.4rc2 hang

I'll send a mail to qemu dev mailing list

[Alexandre DERUMIER]

seem to come from this commit:

http://git.qemu.org/?p=qemu.git;a=commit;h=eabc977973103527bbb8fed69c91cfaa6691f8ab

----- Mail original -----
De: "aderumier" <***@odiso.com>
À: "Emmanuel Kasper" <***@proxmox.com>
Cc: "pve-devel" <pve-***@pve.proxmox.com>
Envoyé: Mercredi 29 Juillet 2015 06:11:51
Objet: Re: [pve-devel] Regression with latest qemu and iothreads option ?

qemu 2.4rc1 works fine

qemu 2.4rc2 hang

I'll send a mail to qemu dev mailing list
_______________________________________________
pve-devel mailing list
pve-***@pve.proxmox.com
http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel

[Alexandre DERUMIER]

a fix patch series has been sent yesterday

http://lists.nongnu.org/archive/html/qemu-devel/2015-07/msg05548.html


----- Mail original -----
De: "aderumier" <***@odiso.com>
À: "Emmanuel Kasper" <***@proxmox.com>
Cc: "pve-devel" <pve-***@pve.proxmox.com>
Envoyé: Mercredi 29 Juillet 2015 06:48:49
Objet: Re: [pve-devel] Regression with latest qemu and iothreads option ?

seem to come from this commit:

http://git.qemu.org/?p=qemu.git;a=commit;h=eabc977973103527bbb8fed69c91cfaa6691f8ab

----- Mail original -----
De: "aderumier" <***@odiso.com>
À: "Emmanuel Kasper" <***@proxmox.com>
Cc: "pve-devel" <pve-***@pve.proxmox.com>
Envoyé: Mercredi 29 Juillet 2015 06:11:51
Objet: Re: [pve-devel] Regression with latest qemu and iothreads option ?

qemu 2.4rc1 works fine

qemu 2.4rc2 hang

I'll send a mail to qemu dev mailing list
_______________________________________________
pve-devel mailing list
pve-***@pve.proxmox.com
http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
_______________________________________________
pve-devel mailing list
pve-***@pve.proxmox.com
http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-devel

[Wolfgang Bumiller]

Post by Alexandre DERUMIER
a fix patch series has been sent yesterday
http://lists.nongnu.org/archive/html/qemu-devel/2015-07/msg05548.html

Doesn't seem to fix it here. Have you tested it successfully?

[Wolfgang Bumiller]

Post by Wolfgang Bumiller

Post by Alexandre DERUMIER
a fix patch series has been sent yesterday
http://lists.nongnu.org/archive/html/qemu-devel/2015-07/msg05548.html

Doesn't seem to fix it here. Have you tested it successfully?

Nevermind, it does work. Just thought they were in master already and
hadn't applied the series manually before testing.

Tested now with the patches applied and they do fix the problem.
Just hope they land in qemu-git/master soon :)

[Alexandre DERUMIER]

This is fixed in qemu 2.4rc3


----- Mail original -----
De: "Wolfgang Bumiller" <***@proxmox.com>
À: "aderumier" <***@odiso.com>
Cc: "pve-devel" <pve-***@pve.proxmox.com>
Envoyé: Mercredi 29 Juillet 2015 10:33:51
Objet: Re: [pve-devel] Regression with latest qemu and iothreads option ?

Post by Wolfgang Bumiller

Post by Alexandre DERUMIER
a fix patch series has been sent yesterday
http://lists.nongnu.org/archive/html/qemu-devel/2015-07/msg05548.html

Doesn't seem to fix it here. Have you tested it successfully?

Nevermind, it does work. Just thought they were in master already and
hadn't applied the series manually before testing.

Tested now with the patches applied and they do fix the problem.
Just hope they land in qemu-git/master soon :)

[Emmanuel Kasper]

Hi

Post by Alexandre DERUMIER
This is fixed in qemu 2.4rc3

I confirm can our pve-qemu-kvm package in version 2.4-1 has this fixed.
Thanks for the update !

Emmanuel