* Bharata B Rao (bharata@xxxxxxxxxxxxxxxxxx) wrote: > On Tue, Sep 08, 2015 at 01:46:52PM +0100, Dr. David Alan Gilbert wrote: > > * Bharata B Rao (bharata@xxxxxxxxxxxxxxxxxx) wrote: > > > On Tue, Sep 08, 2015 at 09:59:47AM +0100, Dr. David Alan Gilbert wrote: > > > > * Bharata B Rao (bharata@xxxxxxxxxxxxxxxxxx) wrote: > > > > > In fact I had successfully done postcopy migration of sPAPR guest with > > > > > this setup. > > > > > > > > Interesting - I'd not got that far myself on power; I was hitting a problem > > > > loading htab ( htab_load() bad index 2113929216 (14848+0 entries) in htab stream (htab_shift=25) ) > > > > > > > > Did you have to make any changes to the qemu code to get that happy? > > > > > > I should have mentioned that I tried only QEMU driven migration within > > > the same host using wp3-postcopy branch of your tree. I don't see the > > > above issue. > > > > > > (qemu) info migrate > > > capabilities: xbzrle: off rdma-pin-all: off auto-converge: off zero-blocks: off compress: off x-postcopy-ram: on > > > Migration status: completed > > > total time: 39432 milliseconds > > > downtime: 162 milliseconds > > > setup: 14 milliseconds > > > transferred ram: 1297209 kbytes > > > throughput: 270.72 mbps > > > remaining ram: 0 kbytes > > > total ram: 4194560 kbytes > > > duplicate: 734015 pages > > > skipped: 0 pages > > > normal: 318469 pages > > > normal bytes: 1273876 kbytes > > > dirty sync count: 4 > > > > > > I will try migration between different hosts soon and check. > > > > I hit that on the same host; are you sure you've switched into postcopy mode; > > i.e. issued a migrate_start_postcopy before the end of migration? > > Sorry I was following your discussion with Li in this thread > > https://www.marc.info/?l=qemu-devel&m=143035620026744&w=4 > > and it wasn't obvious to me that anything apart from turning on the > x-postcopy-ram capability was required :( OK. > So I do see the problem now. > > At the source > ------------- > Error reading data from KVM HTAB fd: Bad file descriptor > Segmentation fault > > At the target > ------------- > htab_load() bad index 2113929216 (14336+0 entries) in htab stream (htab_shift=25) > qemu-system-ppc64: error while loading state section id 56(spapr/htab) > qemu-system-ppc64: postcopy_ram_listen_thread: loadvm failed: -22 > qemu-system-ppc64: VQ 0 size 0x100 Guest index 0x0 inconsistent with Host index 0x1f: delta 0xffe1 > qemu-system-ppc64: error while loading state for instance 0x0 of device 'pci@800000020000000:00.0/virtio-net' > *** Error in `./ppc64-softmmu/qemu-system-ppc64': corrupted double-linked list: 0x00000100241234a0 *** > ======= Backtrace: ========= > /lib64/power8/libc.so.6Segmentation fault Good - my current world has got rid of the segfaults/corruption in the cleanup on power - but those are only after it stumbled over the htab problem. I don't know the innards of power/htab, so if you've got any pointers on what upset it I'd be happy for some pointers. (We should probably trim the cc - since I don't think this is userfault related). Dave -- Dr. David Alan Gilbert / dgilbert@xxxxxxxxxx / Manchester, UK -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>