Re: [Qemu-devel] [PATCH 0/3] non-migratable devices
On 07/08/11 14:59, Paolo Bonzini wrote: On 07/08/2011 02:47 PM, Gerd Hoffmann wrote: One possibility is to add device name remapping to machine types, like "ide is actually ide-0.14 when using pc-0.14" and put a different VMState in ide-0.14. That isn't very different from subsections. Problem is that the old qemu version doesn't have the section at all, not that it looks somehow different. No, I meant a different qdev name, i.e. mapping the same device name to a different DeviceInfo. That is an idea. This could also replace compat properties (by giving ide-0.14 different default values for the properties) and thereby move the compat info from hw/pc.c to hw/ide/xxx.c. cheers, Gerd
Re: [Qemu-devel] [PATCH 0/3] non-migratable devices
On 07/08/2011 02:47 PM, Gerd Hoffmann wrote: One possibility is to add device name remapping to machine types, like "ide is actually ide-0.14 when using pc-0.14" and put a different VMState in ide-0.14. That isn't very different from subsections. Problem is that the old qemu version doesn't have the section at all, not that it looks somehow different. No, I meant a different qdev name, i.e. mapping the same device name to a different DeviceInfo. Paolo
Re: [Qemu-devel] [PATCH 0/3] non-migratable devices
Hi, If desired, in the future we can revert this behavior for pc-0.14 and earlier machines. And I'm still looking for a sane way to handle *this*. One possibility is to add device name remapping to machine types, like "ide is actually ide-0.14 when using pc-0.14" and put a different VMState in ide-0.14. That isn't very different from subsections. Problem is that the old qemu version doesn't have the section at all, not that it looks somehow different. cheers, Gerd
Re: [Qemu-devel] [PATCH 0/3] non-migratable devices
Hi, scsi-cd is new in 0.15, older versions have scsi-disk only. That's why we should take the occasion to add the empty vmstate at least to it. Ok, good opportunity in that specific case. For other devices, it's better to make the breakage in a single version. It also allows to make 0.15 the "flag day" where each device shall have a VMState or the entire VM will not be migratable. Not that easy given that we didn't fully migrate to vmstate yet, otherwise we could simply fail migration in case we find any device with qdev->vmsd == NULL. If desired, in the future we can revert this behavior for pc-0.14 and earlier machines. And I'm still looking for a sane way to handle *this*. cheers, Gerd
Re: [Qemu-devel] [PATCH 0/3] non-migratable devices
On 07/08/2011 01:47 PM, Gerd Hoffmann wrote: scsi-cd is new in 0.15, older versions have scsi-disk only. That's why we should take the occasion to add the empty vmstate at least to it. Ok, good opportunity in that specific case. For other devices, it's better to make the breakage in a single version. It also allows to make 0.15 the "flag day" where each device shall have a VMState or the entire VM will not be migratable. Not that easy given that we didn't fully migrate to vmstate yet, otherwise we could simply fail migration in case we find any device with qdev->vmsd == NULL. You can always add #define VMSD_NONE ((const VMStateDescription *) 1) If desired, in the future we can revert this behavior for pc-0.14 and earlier machines. And I'm still looking for a sane way to handle *this*. One possibility is to add device name remapping to machine types, like "ide is actually ide-0.14 when using pc-0.14" and put a different VMState in ide-0.14. Paolo
Re: [Qemu-devel] [PATCH 0/3] non-migratable devices
Gerd Hoffmann writes: > Hi, > >> For scsi-cd and other empty-but-generally-migratable devices we should >> probably add an empty vmstate, so that any further addition can be done >> as subsections. > > That will break migration to older versions which don't know about the > new sections, even if they are empty ... Send them only when running a sufficiently recent -M?
Re: [Qemu-devel] [PATCH 0/3] non-migratable devices
On 07/08/2011 11:59 AM, Gerd Hoffmann wrote: For scsi-cd and other empty-but-generally-migratable devices we should probably add an empty vmstate, so that any further addition can be done as subsections. That will break migration to older versions which don't know about the new sections, even if they are empty ... scsi-cd is new in 0.15, older versions have scsi-disk only. That's why we should take the occasion to add the empty vmstate at least to it. For other devices, it's better to make the breakage in a single version. It also allows to make 0.15 the "flag day" where each device shall have a VMState or the entire VM will not be migratable. If desired, in the future we can revert this behavior for pc-0.14 and earlier machines. Paolo
Re: [Qemu-devel] [PATCH 0/3] non-migratable devices
On 07/08/2011 10:53 AM, Gerd Hoffmann wrote: Hi, This patch series adds an easy way to tag devices as non-migratable puts it into use for ahci and ehci. Gerd Hoffmann (3): vmstate: add no_migrate flag to VMStateDescription ahci doesn't support migration ehci doesn't support migration hw/hw.h |1 + hw/ide/ich.c |6 ++ hw/usb-ehci.c |6 ++ savevm.c |1 + 4 files changed, 14 insertions(+), 0 deletions(-) ACK series For scsi-cd and other empty-but-generally-migratable devices we should probably add an empty vmstate, so that any further addition can be done as subsections. Paolo
Re: [Qemu-devel] [PATCH 0/3] non-migratable devices
Hi, For scsi-cd and other empty-but-generally-migratable devices we should probably add an empty vmstate, so that any further addition can be done as subsections. That will break migration to older versions which don't know about the new sections, even if they are empty ... cheers, Gerd
[Qemu-devel] [PATCH 0/3] non-migratable devices
Hi, This patch series adds an easy way to tag devices as non-migratable puts it into use for ahci and ehci. Gerd Hoffmann (3): vmstate: add no_migrate flag to VMStateDescription ahci doesn't support migration ehci doesn't support migration hw/hw.h |1 + hw/ide/ich.c |6 ++ hw/usb-ehci.c |6 ++ savevm.c |1 + 4 files changed, 14 insertions(+), 0 deletions(-)
