On 02/17/17 19:34, Ben Warren wrote: > >> On Feb 17, 2017, at 8:03 AM, Laszlo Ersek <ler...@redhat.com >> <mailto:ler...@redhat.com>> wrote: >> >> On 02/17/17 16:33, Ben Warren wrote: >>> >>>> On Feb 17, 2017, at 2:43 AM, Igor Mammedov <imamm...@redhat.com >>>> <mailto:imamm...@redhat.com> >>>> <mailto:imamm...@redhat.com>> wrote: >>>> >>>> On Thu, 16 Feb 2017 15:15:36 -0800 >>>> b...@skyportsystems.com >>>> <mailto:b...@skyportsystems.com> <mailto:b...@skyportsystems.com> wrote: >>>> >>>>> From: Ben Warren <b...@skyportsystems.com >>>>> <mailto:b...@skyportsystems.com> <mailto:b...@skyportsystems.com>> >>>>> >>>>> This implements the VM Generation ID feature by passing a 128-bit >>>>> GUID to the guest via a fw_cfg blob. >>>>> Any time the GUID changes, an ACPI notify event is sent to the guest >>>>> >>>>> The user interface is a simple device with one parameter: >>>>> - guid (string, must be "auto" or in UUID format >>>>> xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx) >>>> I've given it some testing with WS2012R2 and v4 patches for Seabios, >>>> >>>> Windows is able to read initial GUID allocation and writeback >>>> seems to work somehow: >>>> >>>> (qemu) info vm-generation-id >>>> c109c09b-0e8b-42d5-9b33-8409c9dcd16c >>>> >>>> vmgenid client in Windows reads it as 2 following 64bit integers: >>>> 42d50e8bc109c09b:6cd1dcc90984339b >>>> >>>> However update path/restore from snapshot doesn't >>>> here is as I've tested it: >>>> >>>> qemu-system-x86_64 -device vmgenid,id=testvgid,guid=auto -monitor stdio >>>> (qemu) info vm-generation-id >>>> c109c09b-0e8b-42d5-9b33-8409c9dcd16c >>>> (qemu) stop >>>> (qemu) migrate "exec:gzip -c > STATEFILE.gz" >>>> (qemu) quit >>>> >>>> qemu-system-x86_64 -device vmgenid,id=testvgid,guid=auto -monitor stdio >>>> -incoming "exec: gzip -c -d STATEFILE.gz" >>>> (qemu) info vm-generation-id >>>> 28b587fa-991b-4267-80d7-9cf28b746fe9 >>>> >>>> guest >>>> 1. doesn't get GPE notification that it must receive >>>> 2. vmgenid client in Windows reads the same value >>>> 42d50e8bc109c09b:6cd1dcc90984339b >>>> >>> Strange, this was working for me, but with a slightly different test >>> method: >>> >>> * I use virsh save/restore >> >> Awesome, this actually what I should try. All my guests are managed by >> libvirt (with the occasional <qemu:arg>, for development), and direct >> QEMU monitor commands such as >> >> virsh qemu-monitor-command ovmf.rhel7 --hmp 'info vm-generation-id' >> >> only work for me if they are reasonably non-intrusive. >> >>> * While I do later testing with Windows, during development I use a >>> Linux kernel module I wrote that keeps track of GUID and >>> notifications. I’m happy to share this with you if interested. >> >> Please do. If you have a public git repo somewhere, that would be >> awesome. (Bonus points if the module builds out-of-tree, if the >> kernel-devel package is installed.) >> > Here you go: > https://github.com/ben-skyportsystems/vmgenid-test
Ah, thanks -- I apologize, I stopped refreshing my incoming email while I was testing and writing up the results. I'll stash this for later though. Thanks! Laszlo > I don’t know if something like this would ever be accepted into the > Linux kernel, but it has been invaluable to me, and I’d like to see it > somewhere better. > >> NB: while the set-id monitor command was part of the series, I did test >> it to the extent that I checked the SCI ("ACPI interrupt") count in the >> guest, in /proc/interrupts. I did see it increase, so minimally the SCI >> injection was fine. >> >> Thanks! >> Laszlo >> >>> I’ll dig into this morning. >>> >>> —Ben >>> <snip> >