diff mbox series

[PULL,v4,42/83] virtio-rng-pci: Allow setting nvectors, so we can use MSI-X

Message ID 20221107224600.934080-43-mst@redhat.com (mailing list archive)
State New, archived
Headers show
Series [PULL,v4,01/83] hw/i386/e820: remove legacy reserved entries for e820 | expand

Commit Message

Michael S. Tsirkin Nov. 7, 2022, 10:50 p.m. UTC 
From: David Daney <david.daney@fungible.com>

Most other virtio-pci devices allow MSI-X, let's have it for rng too.

Signed-off-by: David Daney <david.daney@fungible.com>
Reviewed-by: Marcin Nowakowski <marcin.nowakowski@fungible.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@fungible.com>
Message-Id: <20221014160947.66105-1-philmd@fungible.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 hw/virtio/virtio-rng-pci.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

Comments

Dr. David Alan Gilbert Jan. 9, 2023, 10:20 a.m. UTC | #1 
* Michael S. Tsirkin (mst@redhat.com) wrote:
> From: David Daney <david.daney@fungible.com>
> 
> Most other virtio-pci devices allow MSI-X, let's have it for rng too.
> 
> Signed-off-by: David Daney <david.daney@fungible.com>
> Reviewed-by: Marcin Nowakowski <marcin.nowakowski@fungible.com>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@fungible.com>
> Message-Id: <20221014160947.66105-1-philmd@fungible.com>
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

This breaks migration compatibility 7.1->7.2 :

(qemu) qemu: get_pci_config_device: Bad config data: i=0x34 read: 84 device: 98 cmask: ff wmask: 0 w1cmask:0
qemu: Failed to load PCIDevice:config
qemu: Failed to load virtio-rng:virtio
qemu: error while loading state for instance 0x0 of device '0000:00:03.0/virtio-rng'
qemu: load of migration failed: Invalid argument

because the destination is configured with msi-x but the source isn't.

The fix is in theory simple:
diff --git a/hw/core/machine.c b/hw/core/machine.c
index f589b92909..45459d1cef 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -45,6 +45,7 @@ const size_t hw_compat_7_2_len = G_N_ELEMENTS(hw_compat_7_2);
 
 GlobalProperty hw_compat_7_1[] = {
     { "virtio-device", "queue_reset", "false" },
+    { "virtio-rng-pci", "vectors", "0" },
 };
 const size_t hw_compat_7_1_len = G_N_ELEMENTS(hw_compat_7_1);

the gotcha is that will break 7.2->7.2-fixed.

(I guess you can also work around it by explicitly passing vectors=0 to
the virtio-rng on the cli)

Does anyone have preferences as to whether that should be fixed in the
7.2 world or left as is?

This is:
https://bugzilla.redhat.com/show_bug.cgi?id=2155749

Dave

> ---
>  hw/virtio/virtio-rng-pci.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/hw/virtio/virtio-rng-pci.c b/hw/virtio/virtio-rng-pci.c
> index 151ece6f94..6e76f8b57b 100644
> --- a/hw/virtio/virtio-rng-pci.c
> +++ b/hw/virtio/virtio-rng-pci.c
> @@ -13,6 +13,7 @@
>  
>  #include "hw/virtio/virtio-pci.h"
>  #include "hw/virtio/virtio-rng.h"
> +#include "hw/qdev-properties.h"
>  #include "qapi/error.h"
>  #include "qemu/module.h"
>  #include "qom/object.h"
> @@ -31,11 +32,23 @@ struct VirtIORngPCI {
>      VirtIORNG vdev;
>  };
>  
> +static Property virtio_rng_properties[] = {
> +    DEFINE_PROP_BIT("ioeventfd", VirtIOPCIProxy, flags,
> +                    VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, true),
> +    DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors,
> +                       DEV_NVECTORS_UNSPECIFIED),
> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
>  static void virtio_rng_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
>  {
>      VirtIORngPCI *vrng = VIRTIO_RNG_PCI(vpci_dev);
>      DeviceState *vdev = DEVICE(&vrng->vdev);
>  
> +    if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) {
> +        vpci_dev->nvectors = 2;
> +    }
> +
>      if (!qdev_realize(vdev, BUS(&vpci_dev->bus), errp)) {
>          return;
>      }
> @@ -54,6 +67,7 @@ static void virtio_rng_pci_class_init(ObjectClass *klass, void *data)
>      pcidev_k->device_id = PCI_DEVICE_ID_VIRTIO_RNG;
>      pcidev_k->revision = VIRTIO_PCI_ABI_VERSION;
>      pcidev_k->class_id = PCI_CLASS_OTHERS;
> +    device_class_set_props(dc, virtio_rng_properties);
>  }
>  
>  static void virtio_rng_initfn(Object *obj)
> -- 
> MST
> 
>
Michael S. Tsirkin Jan. 9, 2023, 10:38 a.m. UTC | #2 
On Mon, Jan 09, 2023 at 10:20:45AM +0000, Dr. David Alan Gilbert wrote:
> * Michael S. Tsirkin (mst@redhat.com) wrote:
> > From: David Daney <david.daney@fungible.com>
> > 
> > Most other virtio-pci devices allow MSI-X, let's have it for rng too.
> > 
> > Signed-off-by: David Daney <david.daney@fungible.com>
> > Reviewed-by: Marcin Nowakowski <marcin.nowakowski@fungible.com>
> > Signed-off-by: Philippe Mathieu-Daudé <philmd@fungible.com>
> > Message-Id: <20221014160947.66105-1-philmd@fungible.com>
> > Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
> > Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> 
> This breaks migration compatibility 7.1->7.2 :
> 
> (qemu) qemu: get_pci_config_device: Bad config data: i=0x34 read: 84 device: 98 cmask: ff wmask: 0 w1cmask:0
> qemu: Failed to load PCIDevice:config
> qemu: Failed to load virtio-rng:virtio
> qemu: error while loading state for instance 0x0 of device '0000:00:03.0/virtio-rng'
> qemu: load of migration failed: Invalid argument
> 
> because the destination is configured with msi-x but the source isn't.
> 
> The fix is in theory simple:
> diff --git a/hw/core/machine.c b/hw/core/machine.c
> index f589b92909..45459d1cef 100644
> --- a/hw/core/machine.c
> +++ b/hw/core/machine.c
> @@ -45,6 +45,7 @@ const size_t hw_compat_7_2_len = G_N_ELEMENTS(hw_compat_7_2);
>  
>  GlobalProperty hw_compat_7_1[] = {
>      { "virtio-device", "queue_reset", "false" },
> +    { "virtio-rng-pci", "vectors", "0" },
>  };
>  const size_t hw_compat_7_1_len = G_N_ELEMENTS(hw_compat_7_1);
> 
> the gotcha is that will break 7.2->7.2-fixed.
> 
> (I guess you can also work around it by explicitly passing vectors=0 to
> the virtio-rng on the cli)
> 
> Does anyone have preferences as to whether that should be fixed in the
> 7.2 world or left as is?
> 
> This is:
> https://bugzilla.redhat.com/show_bug.cgi?id=2155749
> 
> Dave

I think that yes, it should be fixed in 7.2.


> > ---
> >  hw/virtio/virtio-rng-pci.c | 14 ++++++++++++++
> >  1 file changed, 14 insertions(+)
> > 
> > diff --git a/hw/virtio/virtio-rng-pci.c b/hw/virtio/virtio-rng-pci.c
> > index 151ece6f94..6e76f8b57b 100644
> > --- a/hw/virtio/virtio-rng-pci.c
> > +++ b/hw/virtio/virtio-rng-pci.c
> > @@ -13,6 +13,7 @@
> >  
> >  #include "hw/virtio/virtio-pci.h"
> >  #include "hw/virtio/virtio-rng.h"
> > +#include "hw/qdev-properties.h"
> >  #include "qapi/error.h"
> >  #include "qemu/module.h"
> >  #include "qom/object.h"
> > @@ -31,11 +32,23 @@ struct VirtIORngPCI {
> >      VirtIORNG vdev;
> >  };
> >  
> > +static Property virtio_rng_properties[] = {
> > +    DEFINE_PROP_BIT("ioeventfd", VirtIOPCIProxy, flags,
> > +                    VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, true),
> > +    DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors,
> > +                       DEV_NVECTORS_UNSPECIFIED),
> > +    DEFINE_PROP_END_OF_LIST(),
> > +};
> > +
> >  static void virtio_rng_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
> >  {
> >      VirtIORngPCI *vrng = VIRTIO_RNG_PCI(vpci_dev);
> >      DeviceState *vdev = DEVICE(&vrng->vdev);
> >  
> > +    if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) {
> > +        vpci_dev->nvectors = 2;
> > +    }
> > +
> >      if (!qdev_realize(vdev, BUS(&vpci_dev->bus), errp)) {
> >          return;
> >      }
> > @@ -54,6 +67,7 @@ static void virtio_rng_pci_class_init(ObjectClass *klass, void *data)
> >      pcidev_k->device_id = PCI_DEVICE_ID_VIRTIO_RNG;
> >      pcidev_k->revision = VIRTIO_PCI_ABI_VERSION;
> >      pcidev_k->class_id = PCI_CLASS_OTHERS;
> > +    device_class_set_props(dc, virtio_rng_properties);
> >  }
> >  
> >  static void virtio_rng_initfn(Object *obj)
> > -- 
> > MST
> > 
> > 
> -- 
> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
Dr. David Alan Gilbert Jan. 9, 2023, 10:43 a.m. UTC | #3 
* Michael S. Tsirkin (mst@redhat.com) wrote:
> On Mon, Jan 09, 2023 at 10:20:45AM +0000, Dr. David Alan Gilbert wrote:
> > * Michael S. Tsirkin (mst@redhat.com) wrote:
> > > From: David Daney <david.daney@fungible.com>
> > > 
> > > Most other virtio-pci devices allow MSI-X, let's have it for rng too.
> > > 
> > > Signed-off-by: David Daney <david.daney@fungible.com>
> > > Reviewed-by: Marcin Nowakowski <marcin.nowakowski@fungible.com>
> > > Signed-off-by: Philippe Mathieu-Daudé <philmd@fungible.com>
> > > Message-Id: <20221014160947.66105-1-philmd@fungible.com>
> > > Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
> > > Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
> > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > 
> > This breaks migration compatibility 7.1->7.2 :
> > 
> > (qemu) qemu: get_pci_config_device: Bad config data: i=0x34 read: 84 device: 98 cmask: ff wmask: 0 w1cmask:0
> > qemu: Failed to load PCIDevice:config
> > qemu: Failed to load virtio-rng:virtio
> > qemu: error while loading state for instance 0x0 of device '0000:00:03.0/virtio-rng'
> > qemu: load of migration failed: Invalid argument
> > 
> > because the destination is configured with msi-x but the source isn't.
> > 
> > The fix is in theory simple:
> > diff --git a/hw/core/machine.c b/hw/core/machine.c
> > index f589b92909..45459d1cef 100644
> > --- a/hw/core/machine.c
> > +++ b/hw/core/machine.c
> > @@ -45,6 +45,7 @@ const size_t hw_compat_7_2_len = G_N_ELEMENTS(hw_compat_7_2);
> >  
> >  GlobalProperty hw_compat_7_1[] = {
> >      { "virtio-device", "queue_reset", "false" },
> > +    { "virtio-rng-pci", "vectors", "0" },
> >  };
> >  const size_t hw_compat_7_1_len = G_N_ELEMENTS(hw_compat_7_1);
> > 
> > the gotcha is that will break 7.2->7.2-fixed.
> > 
> > (I guess you can also work around it by explicitly passing vectors=0 to
> > the virtio-rng on the cli)
> > 
> > Does anyone have preferences as to whether that should be fixed in the
> > 7.2 world or left as is?
> > 
> > This is:
> > https://bugzilla.redhat.com/show_bug.cgi?id=2155749
> > 
> > Dave
> 
> I think that yes, it should be fixed in 7.2.

OK, I'll resend that as a patch in a mo.

Dave

> 
> > > ---
> > >  hw/virtio/virtio-rng-pci.c | 14 ++++++++++++++
> > >  1 file changed, 14 insertions(+)
> > > 
> > > diff --git a/hw/virtio/virtio-rng-pci.c b/hw/virtio/virtio-rng-pci.c
> > > index 151ece6f94..6e76f8b57b 100644
> > > --- a/hw/virtio/virtio-rng-pci.c
> > > +++ b/hw/virtio/virtio-rng-pci.c
> > > @@ -13,6 +13,7 @@
> > >  
> > >  #include "hw/virtio/virtio-pci.h"
> > >  #include "hw/virtio/virtio-rng.h"
> > > +#include "hw/qdev-properties.h"
> > >  #include "qapi/error.h"
> > >  #include "qemu/module.h"
> > >  #include "qom/object.h"
> > > @@ -31,11 +32,23 @@ struct VirtIORngPCI {
> > >      VirtIORNG vdev;
> > >  };
> > >  
> > > +static Property virtio_rng_properties[] = {
> > > +    DEFINE_PROP_BIT("ioeventfd", VirtIOPCIProxy, flags,
> > > +                    VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, true),
> > > +    DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors,
> > > +                       DEV_NVECTORS_UNSPECIFIED),
> > > +    DEFINE_PROP_END_OF_LIST(),
> > > +};
> > > +
> > >  static void virtio_rng_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
> > >  {
> > >      VirtIORngPCI *vrng = VIRTIO_RNG_PCI(vpci_dev);
> > >      DeviceState *vdev = DEVICE(&vrng->vdev);
> > >  
> > > +    if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) {
> > > +        vpci_dev->nvectors = 2;
> > > +    }
> > > +
> > >      if (!qdev_realize(vdev, BUS(&vpci_dev->bus), errp)) {
> > >          return;
> > >      }
> > > @@ -54,6 +67,7 @@ static void virtio_rng_pci_class_init(ObjectClass *klass, void *data)
> > >      pcidev_k->device_id = PCI_DEVICE_ID_VIRTIO_RNG;
> > >      pcidev_k->revision = VIRTIO_PCI_ABI_VERSION;
> > >      pcidev_k->class_id = PCI_CLASS_OTHERS;
> > > +    device_class_set_props(dc, virtio_rng_properties);
> > >  }
> > >  
> > >  static void virtio_rng_initfn(Object *obj)
> > > -- 
> > > MST
> > > 
> > > 
> > -- 
> > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
>
diff mbox series

Patch

diff --git a/hw/virtio/virtio-rng-pci.c b/hw/virtio/virtio-rng-pci.c
index 151ece6f94..6e76f8b57b 100644
--- a/hw/virtio/virtio-rng-pci.c
+++ b/hw/virtio/virtio-rng-pci.c
@@ -13,6 +13,7 @@ 
 
 #include "hw/virtio/virtio-pci.h"
 #include "hw/virtio/virtio-rng.h"
+#include "hw/qdev-properties.h"
 #include "qapi/error.h"
 #include "qemu/module.h"
 #include "qom/object.h"
@@ -31,11 +32,23 @@  struct VirtIORngPCI {
     VirtIORNG vdev;
 };
 
+static Property virtio_rng_properties[] = {
+    DEFINE_PROP_BIT("ioeventfd", VirtIOPCIProxy, flags,
+                    VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, true),
+    DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors,
+                       DEV_NVECTORS_UNSPECIFIED),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
 static void virtio_rng_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
 {
     VirtIORngPCI *vrng = VIRTIO_RNG_PCI(vpci_dev);
     DeviceState *vdev = DEVICE(&vrng->vdev);
 
+    if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) {
+        vpci_dev->nvectors = 2;
+    }
+
     if (!qdev_realize(vdev, BUS(&vpci_dev->bus), errp)) {
         return;
     }
@@ -54,6 +67,7 @@  static void virtio_rng_pci_class_init(ObjectClass *klass, void *data)
     pcidev_k->device_id = PCI_DEVICE_ID_VIRTIO_RNG;
     pcidev_k->revision = VIRTIO_PCI_ABI_VERSION;
     pcidev_k->class_id = PCI_CLASS_OTHERS;
+    device_class_set_props(dc, virtio_rng_properties);
 }
 
 static void virtio_rng_initfn(Object *obj)