[Qemu-devel] [PATCH 0/2] pcspk migration compatibility

[Qemu-devel] [PATCH 0/2] pcspk migration compatibility

[Dr. David Alan Gilbert (git)]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Hi,
  39c88f56 added VMState for pcspk but turned it on for
all machine types, this breaks backwards compatibility
to older machine types.

  If this is too late for 2.8 then I suggest we take the 1st
of these two patches, which just makes it a property to flip
for those of us who need it.  Adding the 2nd patch after 2.8
might cause problems for people using 2.8 with 2.7 machine
type.

Dave

Dr. David Alan Gilbert (2):
  migration/pcspk: Add a property to state if pcspk is migrated
  migration/pcspk: Turn migration of pcspk off for 2.7 and older

 hw/audio/pcspk.c     | 10 ++++++++++
 include/hw/i386/pc.h |  5 +++++
 2 files changed, 15 insertions(+)

-- 
2.9.3

[Qemu-devel] [PATCH 1/2] migration/pcspk: Add a property to state if pcspk is migrated

[Dr. David Alan Gilbert (git)]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Allow us to turn migration of pcspk off for compatibility.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 hw/audio/pcspk.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/hw/audio/pcspk.c b/hw/audio/pcspk.c
index 984534b..7980022 100644
--- a/hw/audio/pcspk.c
+++ b/hw/audio/pcspk.c
@@ -54,6 +54,7 @@ typedef struct {
     unsigned int play_pos;
     uint8_t data_on;
     uint8_t dummy_refresh_clock;
+    bool migrate;
 } PCSpkState;
 
 static const char *s_spk = "pcspk";
@@ -187,11 +188,19 @@ static void pcspk_realizefn(DeviceState *dev, Error **errp)
     pcspk_state = s;
 }
 
+static bool migrate_needed(void *opaque)
+{
+    PCSpkState *s = opaque;
+
+    return s->migrate;
+}
+
 static const VMStateDescription vmstate_spk = {
     .name = "pcspk",
     .version_id = 1,
     .minimum_version_id = 1,
     .minimum_version_id_old = 1,
+    .needed = migrate_needed,
     .fields      = (VMStateField[]) {
         VMSTATE_UINT8(data_on, PCSpkState),
         VMSTATE_UINT8(dummy_refresh_clock, PCSpkState),
@@ -201,6 +210,7 @@ static const VMStateDescription vmstate_spk = {
 
 static Property pcspk_properties[] = {
     DEFINE_PROP_UINT32("iobase", PCSpkState, iobase,  -1),
+    DEFINE_PROP_BOOL("migrate", PCSpkState, migrate,  true),
     DEFINE_PROP_END_OF_LIST(),
 };
 
-- 
2.9.3

[Qemu-devel] [PATCH 2/2] migration/pcspk: Turn migration of pcspk off for 2.7 and older

[Dr. David Alan Gilbert (git)]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

To keep backwards migration compatibility allow us to turn pcspk
migration off.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 include/hw/i386/pc.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 67a1a9e..4b74130 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -395,6 +395,11 @@ bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *);
         .driver   = "Opteron_G3" "-" TYPE_X86_CPU,\
         .property = "stepping",\
         .value    = "1",\
+    },\
+    {\
+        .driver   = "isa-pcspk",\
+        .property = "migrate",\
+        .value    = "off",\
     },
 
 #define PC_COMPAT_2_6 \
-- 
2.9.3

Re: [Qemu-devel] [PATCH 0/2] pcspk migration compatibility

[Paolo Bonzini]

On 28/11/2016 14:31, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> 
> Hi,
>   39c88f56 added VMState for pcspk but turned it on for
> all machine types, this breaks backwards compatibility
> to older machine types.
> 
>   If this is too late for 2.8 then I suggest we take the 1st
> of these two patches, which just makes it a property to flip
> for those of us who need it.  Adding the 2nd patch after 2.8
> might cause problems for people using 2.8 with 2.7 machine
> type.
> 
> Dave
> 
> Dr. David Alan Gilbert (2):
>   migration/pcspk: Add a property to state if pcspk is migrated
>   migration/pcspk: Turn migration of pcspk off for 2.7 and older
> 
>  hw/audio/pcspk.c     | 10 ++++++++++
>  include/hw/i386/pc.h |  5 +++++
>  2 files changed, 15 insertions(+)
> 

Wow, I didn't know optional sections existed.  We could have used it for
hw/char/parallel.c, but that was added only a couple months before
optional sections.

Queued for 2.8.

Paolo

Re: [Qemu-devel] [PATCH 0/2] pcspk migration compatibility

[Dr. David Alan Gilbert]

* Paolo Bonzini (pbonzini@redhat.com) wrote:
> 
> 
> On 28/11/2016 14:31, Dr. David Alan Gilbert (git) wrote:
> > From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> > 
> > Hi,
> >   39c88f56 added VMState for pcspk but turned it on for
> > all machine types, this breaks backwards compatibility
> > to older machine types.
> > 
> >   If this is too late for 2.8 then I suggest we take the 1st
> > of these two patches, which just makes it a property to flip
> > for those of us who need it.  Adding the 2nd patch after 2.8
> > might cause problems for people using 2.8 with 2.7 machine
> > type.
> > 
> > Dave
> > 
> > Dr. David Alan Gilbert (2):
> >   migration/pcspk: Add a property to state if pcspk is migrated
> >   migration/pcspk: Turn migration of pcspk off for 2.7 and older
> > 
> >  hw/audio/pcspk.c     | 10 ++++++++++
> >  include/hw/i386/pc.h |  5 +++++
> >  2 files changed, 15 insertions(+)
> > 
> 
> Wow, I didn't know optional sections existed.  We could have used it for
> hw/char/parallel.c, but that was added only a couple months before
> optional sections.

I'd forgotten that they existed and was about to write them to
solve this problem, and then found the code I apparently reviewed
a year or so ago :-)

> Queued for 2.8.

Thanks.

Dave

> Paolo
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK

Re: [Qemu-devel] [PATCH 0/2] pcspk migration compatibility

[Amit Shah]

On (Mon) 28 Nov 2016 [13:31:59], Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
> 
> Hi,
>   39c88f56 added VMState for pcspk but turned it on for
> all machine types, this breaks backwards compatibility
> to older machine types.
> 
>   If this is too late for 2.8 then I suggest we take the 1st
> of these two patches, which just makes it a property to flip
> for those of us who need it.  Adding the 2nd patch after 2.8
> might cause problems for people using 2.8 with 2.7 machine
> type.

Reviewed-by: Amit Shah <amit.shah@redhat.com>

We should take both for 2.8, thanks!


		Amit