Re: [PATCH 0/1] vmx: Fix mapping

2021-10-04 Thread Richard W.M. Jones
On Mon, Oct 04, 2021 at 04:50:51PM +0200, Laszlo Ersek wrote: > On 10/04/21 11:59, Richard W.M. Jones wrote: > > It turns out that changing the qemu implementation is painful, > > particularly if we wish to maintain backwards compatibility of the > > command line and live migration. > > > >

Re: [PATCH 0/1] vmx: Fix mapping

2021-10-04 Thread Laszlo Ersek
On 10/04/21 11:59, Richard W.M. Jones wrote: > It turns out that changing the qemu implementation is painful, > particularly if we wish to maintain backwards compatibility of the > command line and live migration. > > Instead I opted to document comprehensively what all the > different hypervisors

Re: [PATCH 0/1] vmx: Fix mapping

2021-10-04 Thread Richard W.M. Jones
It turns out that changing the qemu implementation is painful, particularly if we wish to maintain backwards compatibility of the command line and live migration. Instead I opted to document comprehensively what all the different hypervisors do:

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-30 Thread Richard W.M. Jones
On Thu, Sep 30, 2021 at 09:47:01AM +0100, Daniel P. Berrangé wrote: > On Thu, Sep 30, 2021 at 08:33:48AM +0100, Richard W.M. Jones wrote: > > I propose we deprecate the guid parameter in: > > > > -device vmgenid,guid=8987940a-0951-2cc5-e815-10634ff550b9,id=vmgenid0 > > > > Instead it will be

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-30 Thread Daniel P . Berrangé
On Thu, Sep 30, 2021 at 08:33:48AM +0100, Richard W.M. Jones wrote: > > More data: I found a colleague who has a Hyper-V instance with a > Windows guest and he helped me to understand how Hyper-V represents > generation IDs. Hyper-V has had support for generation IDs since long > before

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-30 Thread Laszlo Ersek
On 09/30/21 09:33, Richard W.M. Jones wrote: > > More data: I found a colleague who has a Hyper-V instance with a > Windows guest and he helped me to understand how Hyper-V represents > generation IDs. Hyper-V has had support for generation IDs since long > before Microsoft proposed the feature

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-30 Thread Richard W.M. Jones
More data: I found a colleague who has a Hyper-V instance with a Windows guest and he helped me to understand how Hyper-V represents generation IDs. Hyper-V has had support for generation IDs since long before Microsoft proposed the feature for standardization. Originally (I think pre-2013)

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-29 Thread Richard W.M. Jones
On Wed, Sep 29, 2021 at 11:10:35AM +0100, Daniel P. Berrangé wrote: > On Wed, Sep 29, 2021 at 10:57:19AM +0100, Richard W.M. Jones wrote: > > Looking at the qemu code the problem IMHO is: > > > >

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-29 Thread Richard W.M. Jones
On Wed, Sep 29, 2021 at 10:46:38AM +0100, Richard W.M. Jones wrote: > I don't know why we decided to use a GUID for this. The feature > itself (https://go.microsoft.com/fwlink/?LinkId=260709) defines it as > an 128 bit / 8 byte number. The only connection to GUIDs is the size. *cough* .. 16

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-29 Thread Richard W.M. Jones
On Wed, Sep 29, 2021 at 11:07:30AM +0100, Daniel P. Berrangé wrote: > I'm not sure if we actually need the full driver or not for testing > purposes. The the GenID is just in memory somewhere, and the somewhere > is reported via ACPI table entry. For QEMU its easy as the data is > exposed via

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-29 Thread Daniel P . Berrangé
On Wed, Sep 29, 2021 at 10:57:19AM +0100, Richard W.M. Jones wrote: > Looking at the qemu code the problem IMHO is: > > https://gitlab.com/qemu-project/qemu/-/blob/6b54a31bf7b403672a798b6443b1930ae6c74dea/docs/specs/vmgenid.txt#L189 >

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-29 Thread Daniel P . Berrangé
On Wed, Sep 29, 2021 at 10:46:39AM +0100, Richard W.M. Jones wrote: > On Wed, Sep 29, 2021 at 10:33:43AM +0100, Daniel P. Berrangé wrote: > > Ultimately as long as the mapping from libvirt XML to guest visible > > string is consistent across drivers, that's sufficient. > > > > > Adding qemu-devel

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-29 Thread Richard W.M. Jones
Looking at the qemu code the problem IMHO is: https://gitlab.com/qemu-project/qemu/-/blob/6b54a31bf7b403672a798b6443b1930ae6c74dea/docs/specs/vmgenid.txt#L189 https://gitlab.com/qemu-project/qemu/-/blob/6b54a31bf7b403672a798b6443b1930ae6c74dea/hw/acpi/vmgenid.c#L37 This byte swapping makes no

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-29 Thread Daniel P . Berrangé
On Wed, Sep 29, 2021 at 10:20:44AM +0100, Richard W.M. Jones wrote: > On Wed, Sep 29, 2021 at 10:01:55AM +0200, Michal Privoznik wrote: > > Apparently, parsing vmx.genid is not as easy as I thought. Anyway, it > > was brought up in a private thread that libvirt doesn't report correct > > UUIDs.

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-29 Thread Richard W.M. Jones
On Wed, Sep 29, 2021 at 10:33:43AM +0100, Daniel P. Berrangé wrote: > On Wed, Sep 29, 2021 at 10:20:44AM +0100, Richard W.M. Jones wrote: > > On Wed, Sep 29, 2021 at 10:01:55AM +0200, Michal Privoznik wrote: > > > Apparently, parsing vmx.genid is not as easy as I thought. Anyway, it > > > was

Re: [PATCH 0/1] vmx: Fix mapping

2021-09-29 Thread Richard W.M. Jones
On Wed, Sep 29, 2021 at 10:01:55AM +0200, Michal Privoznik wrote: > Apparently, parsing vmx.genid is not as easy as I thought. Anyway, it > was brought up in a private thread that libvirt doesn't report correct > UUIDs. For instance for the following input: > > vm.genid = "-8536691797830587195"