[Qemu-devel] [PATCH 0/2] fix virtio-related build breakages

[Qemu-devel] [PATCH 0/2] fix virtio-related build breakages

[Michael Roth]

Build fixes for recent virtio commits. See patches for details.

[Qemu-devel] [PATCH 1/2] virtio-pci: build for uninitialized return value in vq_vector_unmask

[Michael Roth]

Fixes the following:

/home/mdroth/w/qemu2.git/hw/virtio-pci.c: In function
‘kvm_virtio_pci_vector_unmask’:
/home/mdroth/w/qemu2.git/hw/virtio-pci.c:673:12: error: ‘ret’ may be
used uninitialized in this function [-Werror=uninitialized]
cc1: all warnings being treated as errors
make: *** [hw/virtio-pci.o] Error 1
make: *** Waiting for unfinished jobs....

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 hw/virtio-pci.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
index 0b49739..0934246 100644
--- a/hw/virtio-pci.c
+++ b/hw/virtio-pci.c
@@ -616,7 +616,7 @@ static int kvm_virtio_pci_vq_vector_unmask(VirtIOPCIProxy *proxy,
     VirtQueue *vq = virtio_get_queue(proxy->vdev, queue_no);
     EventNotifier *n = virtio_queue_get_guest_notifier(vq);
     VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector];
-    int ret;
+    int ret = 0;
 
     if (irqfd->msg.data != msg.data || irqfd->msg.address != msg.address) {
         ret = kvm_irqchip_update_msi_route(kvm_state, irqfd->virq, msg);
-- 
1.7.9.5

Re: [Qemu-devel] [PATCH 1/2] virtio-pci: build for uninitialized return value in vq_vector_unmask

[Eduardo Habkost]

On Mon, Jan 14, 2013 at 01:20:12PM -0600, Michael Roth wrote:
> Fixes the following:
> 
> /home/mdroth/w/qemu2.git/hw/virtio-pci.c: In function
> ‘kvm_virtio_pci_vector_unmask’:
> /home/mdroth/w/qemu2.git/hw/virtio-pci.c:673:12: error: ‘ret’ may be
> used uninitialized in this function [-Werror=uninitialized]
> cc1: all warnings being treated as errors
> make: *** [hw/virtio-pci.o] Error 1
> make: *** Waiting for unfinished jobs....
> 
> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>

> ---
>  hw/virtio-pci.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
> index 0b49739..0934246 100644
> --- a/hw/virtio-pci.c
> +++ b/hw/virtio-pci.c
> @@ -616,7 +616,7 @@ static int kvm_virtio_pci_vq_vector_unmask(VirtIOPCIProxy *proxy,
>      VirtQueue *vq = virtio_get_queue(proxy->vdev, queue_no);
>      EventNotifier *n = virtio_queue_get_guest_notifier(vq);
>      VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector];
> -    int ret;
> +    int ret = 0;
>  
>      if (irqfd->msg.data != msg.data || irqfd->msg.address != msg.address) {
>          ret = kvm_irqchip_update_msi_route(kvm_state, irqfd->virq, msg);
> -- 
> 1.7.9.5
> 
> 

-- 
Eduardo

Re: [Qemu-devel] [PATCH 1/2] virtio-pci: build for uninitialized return value in vq_vector_unmask

[Anthony Liguori]

Michael Roth <mdroth@linux.vnet.ibm.com> writes:

> Fixes the following:
>
> /home/mdroth/w/qemu2.git/hw/virtio-pci.c: In function
> ‘kvm_virtio_pci_vector_unmask’:
> /home/mdroth/w/qemu2.git/hw/virtio-pci.c:673:12: error: ‘ret’ may be
> used uninitialized in this function [-Werror=uninitialized]
> cc1: all warnings being treated as errors
> make: *** [hw/virtio-pci.o] Error 1
> make: *** Waiting for unfinished jobs....
>
> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

Looks like I didn't have libaio-devel installed on my new development
box :-/

Regards,

Anthony Liguori

> ---
>  hw/virtio-pci.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
> index 0b49739..0934246 100644
> --- a/hw/virtio-pci.c
> +++ b/hw/virtio-pci.c
> @@ -616,7 +616,7 @@ static int kvm_virtio_pci_vq_vector_unmask(VirtIOPCIProxy *proxy,
>      VirtQueue *vq = virtio_get_queue(proxy->vdev, queue_no);
>      EventNotifier *n = virtio_queue_get_guest_notifier(vq);
>      VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector];
> -    int ret;
> +    int ret = 0;
>  
>      if (irqfd->msg.data != msg.data || irqfd->msg.address != msg.address) {
>          ret = kvm_irqchip_update_msi_route(kvm_state, irqfd->virq, msg);
> -- 
> 1.7.9.5

Re: [Qemu-devel] [PATCH 1/2] virtio-pci: build for uninitialized return value in vq_vector_unmask

[Michael S. Tsirkin]

On Mon, Jan 14, 2013 at 01:37:35PM -0600, Anthony Liguori wrote:
> Michael Roth <mdroth@linux.vnet.ibm.com> writes:
> 
> > Fixes the following:
> >
> > /home/mdroth/w/qemu2.git/hw/virtio-pci.c: In function
> > ‘kvm_virtio_pci_vector_unmask’:
> > /home/mdroth/w/qemu2.git/hw/virtio-pci.c:673:12: error: ‘ret’ may be
> > used uninitialized in this function [-Werror=uninitialized]
> > cc1: all warnings being treated as errors
> > make: *** [hw/virtio-pci.o] Error 1
> > make: *** Waiting for unfinished jobs....
> >
> > Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
> 
> Looks like I didn't have libaio-devel installed on my new development
> box :-/
> 
> Regards,
> 
> Anthony Liguori

Me neither. And apparently neither does the buildbot.

> > ---
> >  hw/virtio-pci.c |    2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
> > index 0b49739..0934246 100644
> > --- a/hw/virtio-pci.c
> > +++ b/hw/virtio-pci.c
> > @@ -616,7 +616,7 @@ static int kvm_virtio_pci_vq_vector_unmask(VirtIOPCIProxy *proxy,
> >      VirtQueue *vq = virtio_get_queue(proxy->vdev, queue_no);
> >      EventNotifier *n = virtio_queue_get_guest_notifier(vq);
> >      VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector];
> > -    int ret;
> > +    int ret = 0;
> >  
> >      if (irqfd->msg.data != msg.data || irqfd->msg.address != msg.address) {
> >          ret = kvm_irqchip_update_msi_route(kvm_state, irqfd->virq, msg);
> > -- 
> > 1.7.9.5
> 

[Qemu-devel] [PATCH 2/2] dataplane: fix build breakage on set_guest_notifiers()

[Michael Roth]

virtio_pci_set_guest_notifiers() now takes an additional argument to
specify the number of virtqueues to assign a guest notifier for. This
causes a build breakage for CONFIG_VIRTIO_BLK_DATA_PLANE builds:

/home/mdroth/w/qemu2.git/hw/dataplane/virtio-blk.c: In function
‘virtio_blk_data_plane_start’:
/home/mdroth/w/qemu2.git/hw/dataplane/virtio-blk.c:451:47: error: too
few arguments to function ‘s->vdev->binding->set_guest_notifiers’
/home/mdroth/w/qemu2.git/hw/dataplane/virtio-blk.c: In function
‘virtio_blk_data_plane_stop’:
/home/mdroth/w/qemu2.git/hw/dataplane/virtio-blk.c:511:5: error: too few
arguments to function ‘s->vdev->binding->set_guest_notifiers’
make[1]: *** [hw/dataplane/virtio-blk.o] Error 1
make[1]: *** Waiting for unfinished jobs....
make: *** [subdir-x86_64-softmmu] Error 2

Fix this by passing 1 as the number of virtqueues to assign notifiers
for.

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 hw/dataplane/virtio-blk.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hw/dataplane/virtio-blk.c b/hw/dataplane/virtio-blk.c
index 1f7346e..4b26faa 100644
--- a/hw/dataplane/virtio-blk.c
+++ b/hw/dataplane/virtio-blk.c
@@ -447,7 +447,7 @@ void virtio_blk_data_plane_start(VirtIOBlockDataPlane *s)
     event_poll_init(&s->event_poll);
 
     /* Set up guest notifier (irq) */
-    if (s->vdev->binding->set_guest_notifiers(s->vdev->binding_opaque,
+    if (s->vdev->binding->set_guest_notifiers(s->vdev->binding_opaque, 1,
                                               true) != 0) {
         fprintf(stderr, "virtio-blk failed to set guest notifier, "
                 "ensure -enable-kvm is set\n");
@@ -508,7 +508,7 @@ void virtio_blk_data_plane_stop(VirtIOBlockDataPlane *s)
     event_poll_cleanup(&s->event_poll);
 
     /* Clean up guest notifier (irq) */
-    s->vdev->binding->set_guest_notifiers(s->vdev->binding_opaque, false);
+    s->vdev->binding->set_guest_notifiers(s->vdev->binding_opaque, 1, false);
 
     vring_teardown(&s->vring);
 }
-- 
1.7.9.5

Re: [Qemu-devel] [PATCH 2/2] dataplane: fix build breakage on set_guest_notifiers()

[Stefan Hajnoczi]

On Mon, Jan 14, 2013 at 01:20:13PM -0600, Michael Roth wrote:
> virtio_pci_set_guest_notifiers() now takes an additional argument to
> specify the number of virtqueues to assign a guest notifier for. This
> causes a build breakage for CONFIG_VIRTIO_BLK_DATA_PLANE builds:
> 
> /home/mdroth/w/qemu2.git/hw/dataplane/virtio-blk.c: In function
> ‘virtio_blk_data_plane_start’:
> /home/mdroth/w/qemu2.git/hw/dataplane/virtio-blk.c:451:47: error: too
> few arguments to function ‘s->vdev->binding->set_guest_notifiers’
> /home/mdroth/w/qemu2.git/hw/dataplane/virtio-blk.c: In function
> ‘virtio_blk_data_plane_stop’:
> /home/mdroth/w/qemu2.git/hw/dataplane/virtio-blk.c:511:5: error: too few
> arguments to function ‘s->vdev->binding->set_guest_notifiers’
> make[1]: *** [hw/dataplane/virtio-blk.o] Error 1
> make[1]: *** Waiting for unfinished jobs....
> make: *** [subdir-x86_64-softmmu] Error 2
> 
> Fix this by passing 1 as the number of virtqueues to assign notifiers
> for.
> 
> Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
> ---
>  hw/dataplane/virtio-blk.c |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)

Thanks for the fix, Mike!

Stefan

Re: [Qemu-devel] [PATCH 0/2] fix virtio-related build breakages

[Anthony Liguori]

Thanks, applied.

Regards,

Anthony Liguori