Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-07-10 Thread Christian Borntraeger
On 07/04/2017 10:16 AM, Martin Schwidefsky wrote: > On Tue, 4 Jul 2017 09:48:11 +0200 > Christian Borntraeger wrote: > >> On 07/03/2017 09:07 PM, Dr. David Alan Gilbert wrote: >>> * Michael S. Tsirkin (m...@redhat.com) wrote: On Fri, Jun 30, 2017 at 05:31:39PM +0100, Dr. David Alan Gilbert

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-07-04 Thread Martin Schwidefsky
On Tue, 4 Jul 2017 09:48:11 +0200 Christian Borntraeger wrote: > On 07/03/2017 09:07 PM, Dr. David Alan Gilbert wrote: > > * Michael S. Tsirkin (m...@redhat.com) wrote: > >> On Fri, Jun 30, 2017 at 05:31:39PM +0100, Dr. David Alan Gilbert wrote: > >>> * Christian Borntraeger (borntrae...@de.i

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-07-04 Thread Christian Borntraeger
On 07/04/2017 10:16 AM, Martin Schwidefsky wrote: > On Tue, 4 Jul 2017 09:48:11 +0200 > Christian Borntraeger wrote: > >> On 07/03/2017 09:07 PM, Dr. David Alan Gilbert wrote: >>> * Michael S. Tsirkin (m...@redhat.com) wrote: On Fri, Jun 30, 2017 at 05:31:39PM +0100, Dr. David Alan Gilbert

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-07-04 Thread Christian Borntraeger
On 07/03/2017 09:07 PM, Dr. David Alan Gilbert wrote: > * Michael S. Tsirkin (m...@redhat.com) wrote: >> On Fri, Jun 30, 2017 at 05:31:39PM +0100, Dr. David Alan Gilbert wrote: >>> * Christian Borntraeger (borntrae...@de.ibm.com) wrote: On 04/26/2017 01:45 PM, Christian Borntraeger wrote:

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-07-03 Thread Dr. David Alan Gilbert
* Michael S. Tsirkin (m...@redhat.com) wrote: > On Fri, Jun 30, 2017 at 05:31:39PM +0100, Dr. David Alan Gilbert wrote: > > * Christian Borntraeger (borntrae...@de.ibm.com) wrote: > > > On 04/26/2017 01:45 PM, Christian Borntraeger wrote: > > > > > > >> Hmm, I have a theory, if the flags field has

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-07-03 Thread Michael S. Tsirkin
On Fri, Jun 30, 2017 at 05:31:39PM +0100, Dr. David Alan Gilbert wrote: > * Christian Borntraeger (borntrae...@de.ibm.com) wrote: > > On 04/26/2017 01:45 PM, Christian Borntraeger wrote: > > > > >> Hmm, I have a theory, if the flags field has bit 1 set, i.e. > > >> RAM_SAVE_FLAG_COMPRESS > > >> t

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-07-03 Thread Christian Borntraeger
On 06/30/2017 06:31 PM, Dr. David Alan Gilbert wrote: > * Christian Borntraeger (borntrae...@de.ibm.com) wrote: >> On 04/26/2017 01:45 PM, Christian Borntraeger wrote: >> Hmm, I have a theory, if the flags field has bit 1 set, i.e. RAM_SAVE_FLAG_COMPRESS then try changing ram_handle

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-06-30 Thread Dr. David Alan Gilbert
* Christian Borntraeger (borntrae...@de.ibm.com) wrote: > On 04/26/2017 01:45 PM, Christian Borntraeger wrote: > > >> Hmm, I have a theory, if the flags field has bit 1 set, i.e. > >> RAM_SAVE_FLAG_COMPRESS > >> then try changing ram_handle_compressed to always do the memset. > > > > FWIW, chang

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-26 Thread Christian Borntraeger
On 04/26/2017 01:45 PM, Christian Borntraeger wrote: >> Hmm, I have a theory, if the flags field has bit 1 set, i.e. >> RAM_SAVE_FLAG_COMPRESS >> then try changing ram_handle_compressed to always do the memset. > > FWIW, changing ram_handle_compressed to always memset makes the problem go > awa

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-26 Thread Christian Borntraeger
On 04/26/2017 01:01 PM, Dr. David Alan Gilbert wrote: > * Christian Borntraeger (borntrae...@de.ibm.com) wrote: >> On 04/24/2017 09:12 PM, Dr. David Alan Gilbert wrote: >>> * Christian Borntraeger (borntrae...@de.ibm.com) wrote: On 04/24/2017 04:35 PM, Dr. David Alan Gilbert wrote: > * Chr

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-26 Thread Christian Borntraeger
On 04/26/2017 01:01 PM, Dr. David Alan Gilbert wrote: > * Christian Borntraeger (borntrae...@de.ibm.com) wrote: >> On 04/24/2017 09:12 PM, Dr. David Alan Gilbert wrote: >>> * Christian Borntraeger (borntrae...@de.ibm.com) wrote: On 04/24/2017 04:35 PM, Dr. David Alan Gilbert wrote: > * Chr

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-26 Thread Dr. David Alan Gilbert
* Christian Borntraeger (borntrae...@de.ibm.com) wrote: > On 04/24/2017 09:12 PM, Dr. David Alan Gilbert wrote: > > * Christian Borntraeger (borntrae...@de.ibm.com) wrote: > >> On 04/24/2017 04:35 PM, Dr. David Alan Gilbert wrote: > >>> * Christian Borntraeger (borntrae...@de.ibm.com) wrote: >

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-26 Thread Christian Borntraeger
On 04/26/2017 11:59 AM, Christian Borntraeger wrote: > source: > 28863@1493200554.418978:qemu_savevm_send_postcopy_ram_discard s390.ram: 12d > 28863@1493200554.419047:qemu_savevm_send_postcopy_ram_discard s390.ram: 12d > 28863@1493200554.419056:qemu_savevm_send_postcopy_ram_discard s390.ram: 12d >

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-26 Thread Christian Borntraeger
On 04/24/2017 09:12 PM, Dr. David Alan Gilbert wrote: > * Christian Borntraeger (borntrae...@de.ibm.com) wrote: >> On 04/24/2017 04:35 PM, Dr. David Alan Gilbert wrote: >>> * Christian Borntraeger (borntrae...@de.ibm.com) wrote: On 04/24/2017 12:53 PM, Dr. David Alan Gilbert wrote: > * Chr

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-25 Thread Christian Borntraeger
On 04/24/2017 09:12 PM, Dr. David Alan Gilbert wrote: > * Christian Borntraeger (borntrae...@de.ibm.com) wrote: >> On 04/24/2017 04:35 PM, Dr. David Alan Gilbert wrote: >>> * Christian Borntraeger (borntrae...@de.ibm.com) wrote: On 04/24/2017 12:53 PM, Dr. David Alan Gilbert wrote: > * Chr

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-24 Thread Dr. David Alan Gilbert
* Christian Borntraeger (borntrae...@de.ibm.com) wrote: > On 04/24/2017 04:35 PM, Dr. David Alan Gilbert wrote: > > * Christian Borntraeger (borntrae...@de.ibm.com) wrote: > >> On 04/24/2017 12:53 PM, Dr. David Alan Gilbert wrote: > >>> * Christian Borntraeger (borntrae...@de.ibm.com) wrote: >

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-24 Thread Christian Borntraeger
On 04/24/2017 04:35 PM, Dr. David Alan Gilbert wrote: > * Christian Borntraeger (borntrae...@de.ibm.com) wrote: >> On 04/24/2017 12:53 PM, Dr. David Alan Gilbert wrote: >>> * Christian Borntraeger (borntrae...@de.ibm.com) wrote: David, Juan, I can trigger a hang of postcopy migration

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-24 Thread Dr. David Alan Gilbert
* Christian Borntraeger (borntrae...@de.ibm.com) wrote: > On 04/24/2017 12:53 PM, Dr. David Alan Gilbert wrote: > > * Christian Borntraeger (borntrae...@de.ibm.com) wrote: > >> David, Juan, > >> > >> I can trigger a hang of postcopy migration (when I do it early) so > >> that both sides are in pau

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-24 Thread Christian Borntraeger
On 04/24/2017 12:53 PM, Dr. David Alan Gilbert wrote: FWIW, the sending side calltrace looks like: > Thread 8 (Thread 0x3ff509aa910 (LWP 58594)): #0 0x03ff9d588ca4 in pthread_join () from target:/lib64/libpthread.so.0 #1 0x01493d4a in qemu_thread_join (thread=0x16c7e78 ) at /root/

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-24 Thread Christian Borntraeger
On 04/24/2017 12:53 PM, Dr. David Alan Gilbert wrote: > * Christian Borntraeger (borntrae...@de.ibm.com) wrote: >> David, Juan, >> >> I can trigger a hang of postcopy migration (when I do it early) so >> that both sides are in paused state. Looks like one thread is still >> loading vmstates for vi

Re: [Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-24 Thread Dr. David Alan Gilbert
* Christian Borntraeger (borntrae...@de.ibm.com) wrote: > David, Juan, > > I can trigger a hang of postcopy migration (when I do it early) so that > both sides are in paused state. Looks like one thread is still loading > vmstates for virtio and this load accesses guest memory and triggers > a use

[Qemu-devel] postcopy migration hangs while loading virtio state

2017-04-24 Thread Christian Borntraeger
David, Juan, I can trigger a hang of postcopy migration (when I do it early) so that both sides are in paused state. Looks like one thread is still loading vmstates for virtio and this load accesses guest memory and triggers a userfault. Thread 1 (Thread 0x3ffa2f45f00 (LWP 21122)): #0 0x000