| Message ID | 20240402150218.270587-2-lulu@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | virtio-pci: Fix the crash when the vector changes back from VIRTIO_NO_VECTOR | expand |
On Tue, Apr 2, 2024 at 11:02 PM Cindy Lu <lulu@redhat.com> wrote: > > When the guest calls virtio_stop and then virtio_reset, Guests could not call those functions directly, it is triggered by for example writing to some of the registers like reset or others. > the vector will change > to VIRTIO_NO_VECTOR and the IRQFD for this vector will be released. After that > If you want to change the vector back, What do you mean by "change the vector back"? Something like assign VIRTIO_MSI_NO_VECTOR to vector 0 assign X to vector 0 And I guess what you meant is to configure the vector after DRIVER_OK. > it will cause a crash. > > To fix this, we need to call the function "kvm_virtio_pci_vector_use_one()" > when the vector changes back from VIRTIO_NO_VECTOR > > Signed-off-by: Cindy Lu <lulu@redhat.com> > --- > hw/virtio/virtio-pci.c | 31 ++++++++++++++++++++++++++++--- > 1 file changed, 28 insertions(+), 3 deletions(-) > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > index e433879542..45f3ab38c3 100644 > --- a/hw/virtio/virtio-pci.c > +++ b/hw/virtio/virtio-pci.c > @@ -874,12 +874,14 @@ static int virtio_pci_get_notifier(VirtIOPCIProxy *proxy, int queue_no, > return 0; > } > > -static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > +static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no, > + bool recovery) > { > unsigned int vector; > int ret; > EventNotifier *n; > PCIDevice *dev = &proxy->pci_dev; > + VirtIOIRQFD *irqfd; > VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); > VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); > > @@ -890,10 +892,21 @@ static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > if (vector >= msix_nr_vectors_allocated(dev)) { > return 0; > } > + /* > + * if this is recovery and irqfd still in use, means the irqfd was not > + * release before and don't need to set up again > + */ > + if (recovery) { > + irqfd = &proxy->vector_irqfd[vector]; > + if (irqfd->users != 0) { > + return 0; > + } > + } > ret = kvm_virtio_pci_vq_vector_use(proxy, vector); > if (ret < 0) { > goto undo; > } > + > /* > * If guest supports masking, set up irqfd now. > * Otherwise, delay until unmasked in the frontend. > @@ -932,14 +945,14 @@ static int kvm_virtio_pci_vector_vq_use(VirtIOPCIProxy *proxy, int nvqs) > if (!virtio_queue_get_num(vdev, queue_no)) { > return -1; > } > - ret = kvm_virtio_pci_vector_use_one(proxy, queue_no); > + ret = kvm_virtio_pci_vector_use_one(proxy, queue_no, false); > } > return ret; > } > > static int kvm_virtio_pci_vector_config_use(VirtIOPCIProxy *proxy) > { > - return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX); > + return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, false); > } > > static void kvm_virtio_pci_vector_release_one(VirtIOPCIProxy *proxy, > @@ -1570,7 +1583,13 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, > } else { > val = VIRTIO_NO_VECTOR; > } > + vector = vdev->config_vector; > vdev->config_vector = val; > + /*check if the vector need to recovery*/ > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > + kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, true); > + } This looks too tricky. Think hard of this. I think it's better to split this into two parts: 1) a series that disables config irqfd for vhost-net, this series needs to be backported to -stable which needs to be conservative. It looks more like your V1, but let's add a boolean for pci proxy. 2) a series that deal with the msix vector configuration after driver_ok, we probably need some refactoring to do per vq use instead of the current loop in DRIVER_OK Does this make sense? Thanks > break; > case VIRTIO_PCI_COMMON_STATUS: > if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { > @@ -1611,6 +1630,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, > val = VIRTIO_NO_VECTOR; > } > virtio_queue_set_vector(vdev, vdev->queue_sel, val); > + > + /*check if the vector need to recovery*/ > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > + kvm_virtio_pci_vector_use_one(proxy, vdev->queue_sel, true); > + } > break; > case VIRTIO_PCI_COMMON_Q_ENABLE: > if (val == 1) { > -- > 2.43.0 >
On Sun, Apr 7, 2024 at 12:20 PM Jason Wang <jasowang@redhat.com> wrote: > > On Tue, Apr 2, 2024 at 11:02 PM Cindy Lu <lulu@redhat.com> wrote: > > > > When the guest calls virtio_stop and then virtio_reset, > > Guests could not call those functions directly, it is triggered by for > example writing to some of the registers like reset or others. > sure , Will fix this > > the vector will change > > to VIRTIO_NO_VECTOR and the IRQFD for this vector will be released. After that > > If you want to change the vector back, > > What do you mean by "change the vector back"? Something like > > assign VIRTIO_MSI_NO_VECTOR to vector 0 > assign X to vector 0 > yes, the process is something like .... set config_vector = VIRTIO_MSI_NO_VECTOR ... set config_vector = 0 > And I guess what you meant is to configure the vector after DRIVER_OK. > > > > it will cause a crash. > > > > To fix this, we need to call the function "kvm_virtio_pci_vector_use_one()" > > when the vector changes back from VIRTIO_NO_VECTOR > > > > Signed-off-by: Cindy Lu <lulu@redhat.com> > > --- > > hw/virtio/virtio-pci.c | 31 ++++++++++++++++++++++++++++--- > > 1 file changed, 28 insertions(+), 3 deletions(-) > > > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > > index e433879542..45f3ab38c3 100644 > > --- a/hw/virtio/virtio-pci.c > > +++ b/hw/virtio/virtio-pci.c > > @@ -874,12 +874,14 @@ static int virtio_pci_get_notifier(VirtIOPCIProxy *proxy, int queue_no, > > return 0; > > } > > > > -static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > > +static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no, > > + bool recovery) > > { > > unsigned int vector; > > int ret; > > EventNotifier *n; > > PCIDevice *dev = &proxy->pci_dev; > > + VirtIOIRQFD *irqfd; > > VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); > > VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); > > > > @@ -890,10 +892,21 @@ static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > > if (vector >= msix_nr_vectors_allocated(dev)) { > > return 0; > > } > > + /* > > + * if this is recovery and irqfd still in use, means the irqfd was not > > + * release before and don't need to set up again > > + */ > > + if (recovery) { > > + irqfd = &proxy->vector_irqfd[vector]; > > + if (irqfd->users != 0) { > > + return 0; > > + } > > + } > > ret = kvm_virtio_pci_vq_vector_use(proxy, vector); > > if (ret < 0) { > > goto undo; > > } > > + > > /* > > * If guest supports masking, set up irqfd now. > > * Otherwise, delay until unmasked in the frontend. > > @@ -932,14 +945,14 @@ static int kvm_virtio_pci_vector_vq_use(VirtIOPCIProxy *proxy, int nvqs) > > if (!virtio_queue_get_num(vdev, queue_no)) { > > return -1; > > } > > - ret = kvm_virtio_pci_vector_use_one(proxy, queue_no); > > + ret = kvm_virtio_pci_vector_use_one(proxy, queue_no, false); > > } > > return ret; > > } > > > > static int kvm_virtio_pci_vector_config_use(VirtIOPCIProxy *proxy) > > { > > - return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX); > > + return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, false); > > } > > > > static void kvm_virtio_pci_vector_release_one(VirtIOPCIProxy *proxy, > > @@ -1570,7 +1583,13 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, > > } else { > > val = VIRTIO_NO_VECTOR; > > } > > + vector = vdev->config_vector; > > vdev->config_vector = val; > > + /*check if the vector need to recovery*/ > > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > > + kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, true); > > + } > > This looks too tricky. > > Think hard of this. I think it's better to split this into two parts: > > 1) a series that disables config irqfd for vhost-net, this series > needs to be backported to -stable which needs to be conservative. It > looks more like your V1, but let's add a boolean for pci proxy. sure, I wll try this > 2) a series that deal with the msix vector configuration after > driver_ok, we probably need some refactoring to do per vq use instead > of the current loop in DRIVER_OK > Sorry I didn't get what you mean , Do you mean we need to move the check to inside kvm_virtio_pci_vector_vq_use()？ Thanks cindy > Does this make sense? > > Thanks > > > break; > > case VIRTIO_PCI_COMMON_STATUS: > > if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { > > @@ -1611,6 +1630,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, > > val = VIRTIO_NO_VECTOR; > > } > > virtio_queue_set_vector(vdev, vdev->queue_sel, val); > > + > > + /*check if the vector need to recovery*/ > > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > > + kvm_virtio_pci_vector_use_one(proxy, vdev->queue_sel, true); > > + } > > break; > > case VIRTIO_PCI_COMMON_Q_ENABLE: > > if (val == 1) { > > -- > > 2.43.0 > > >
On Sun, Apr 07, 2024 at 12:19:57PM +0800, Jason Wang wrote: > On Tue, Apr 2, 2024 at 11:02 PM Cindy Lu <lulu@redhat.com> wrote: > > > > When the guest calls virtio_stop and then virtio_reset, > > Guests could not call those functions directly, it is triggered by for > example writing to some of the registers like reset or others. > > > the vector will change > > to VIRTIO_NO_VECTOR and the IRQFD for this vector will be released. After that > > If you want to change the vector back, > > What do you mean by "change the vector back"? Something like > > assign VIRTIO_MSI_NO_VECTOR to vector 0 > assign X to vector 0 > > And I guess what you meant is to configure the vector after DRIVER_OK. > > > > it will cause a crash. > > > > To fix this, we need to call the function "kvm_virtio_pci_vector_use_one()" > > when the vector changes back from VIRTIO_NO_VECTOR > > > > Signed-off-by: Cindy Lu <lulu@redhat.com> > > --- > > hw/virtio/virtio-pci.c | 31 ++++++++++++++++++++++++++++--- > > 1 file changed, 28 insertions(+), 3 deletions(-) > > > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > > index e433879542..45f3ab38c3 100644 > > --- a/hw/virtio/virtio-pci.c > > +++ b/hw/virtio/virtio-pci.c > > @@ -874,12 +874,14 @@ static int virtio_pci_get_notifier(VirtIOPCIProxy *proxy, int queue_no, > > return 0; > > } > > > > -static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > > +static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no, > > + bool recovery) > > { > > unsigned int vector; > > int ret; > > EventNotifier *n; > > PCIDevice *dev = &proxy->pci_dev; > > + VirtIOIRQFD *irqfd; > > VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); > > VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); > > > > @@ -890,10 +892,21 @@ static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > > if (vector >= msix_nr_vectors_allocated(dev)) { > > return 0; > > } > > + /* > > + * if this is recovery and irqfd still in use, means the irqfd was not > > + * release before and don't need to set up again > > + */ > > + if (recovery) { > > + irqfd = &proxy->vector_irqfd[vector]; > > + if (irqfd->users != 0) { > > + return 0; > > + } > > + } > > ret = kvm_virtio_pci_vq_vector_use(proxy, vector); > > if (ret < 0) { > > goto undo; > > } > > + > > /* > > * If guest supports masking, set up irqfd now. > > * Otherwise, delay until unmasked in the frontend. > > @@ -932,14 +945,14 @@ static int kvm_virtio_pci_vector_vq_use(VirtIOPCIProxy *proxy, int nvqs) > > if (!virtio_queue_get_num(vdev, queue_no)) { > > return -1; > > } > > - ret = kvm_virtio_pci_vector_use_one(proxy, queue_no); > > + ret = kvm_virtio_pci_vector_use_one(proxy, queue_no, false); > > } > > return ret; > > } > > > > static int kvm_virtio_pci_vector_config_use(VirtIOPCIProxy *proxy) > > { > > - return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX); > > + return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, false); > > } > > > > static void kvm_virtio_pci_vector_release_one(VirtIOPCIProxy *proxy, > > @@ -1570,7 +1583,13 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, > > } else { > > val = VIRTIO_NO_VECTOR; > > } > > + vector = vdev->config_vector; > > vdev->config_vector = val; > > + /*check if the vector need to recovery*/ > > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > > + kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, true); > > + } > > This looks too tricky. > > Think hard of this. I think it's better to split this into two parts: > > 1) a series that disables config irqfd for vhost-net, this series > needs to be backported to -stable which needs to be conservative. It > looks more like your V1, but let's add a boolean for pci proxy. I don't get it. Looks like a huge change to do in stable. All as a replacement to a small 20 line patch? Generally I think irqfd is best used everywhere. > 2) a series that deal with the msix vector configuration after > driver_ok, we probably need some refactoring to do per vq use instead > of the current loop in DRIVER_OK > > Does this make sense? > > Thanks Not really let's fix the bug for starters, refactoring can be done later as appropriate. > > break; > > case VIRTIO_PCI_COMMON_STATUS: > > if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { > > @@ -1611,6 +1630,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, > > val = VIRTIO_NO_VECTOR; > > } > > virtio_queue_set_vector(vdev, vdev->queue_sel, val); > > + > > + /*check if the vector need to recovery*/ > > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > > + kvm_virtio_pci_vector_use_one(proxy, vdev->queue_sel, true); > > + } > > break; > > case VIRTIO_PCI_COMMON_Q_ENABLE: > > if (val == 1) { > > -- > > 2.43.0 > >
On Sun, Apr 7, 2024 at 7:53 PM Michael S. Tsirkin <mst@redhat.com> wrote: > > On Sun, Apr 07, 2024 at 12:19:57PM +0800, Jason Wang wrote: > > On Tue, Apr 2, 2024 at 11:02 PM Cindy Lu <lulu@redhat.com> wrote: > > > > > > When the guest calls virtio_stop and then virtio_reset, > > > > Guests could not call those functions directly, it is triggered by for > > example writing to some of the registers like reset or others. > > > > > the vector will change > > > to VIRTIO_NO_VECTOR and the IRQFD for this vector will be released. After that > > > If you want to change the vector back, > > > > What do you mean by "change the vector back"? Something like > > > > assign VIRTIO_MSI_NO_VECTOR to vector 0 > > assign X to vector 0 > > > > And I guess what you meant is to configure the vector after DRIVER_OK. > > > > > > > it will cause a crash. > > > > > > To fix this, we need to call the function "kvm_virtio_pci_vector_use_one()" > > > when the vector changes back from VIRTIO_NO_VECTOR > > > > > > Signed-off-by: Cindy Lu <lulu@redhat.com> > > > --- > > > hw/virtio/virtio-pci.c | 31 ++++++++++++++++++++++++++++--- > > > 1 file changed, 28 insertions(+), 3 deletions(-) > > > > > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > > > index e433879542..45f3ab38c3 100644 > > > --- a/hw/virtio/virtio-pci.c > > > +++ b/hw/virtio/virtio-pci.c > > > @@ -874,12 +874,14 @@ static int virtio_pci_get_notifier(VirtIOPCIProxy *proxy, int queue_no, > > > return 0; > > > } > > > > > > -static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > > > +static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no, > > > + bool recovery) > > > { > > > unsigned int vector; > > > int ret; > > > EventNotifier *n; > > > PCIDevice *dev = &proxy->pci_dev; > > > + VirtIOIRQFD *irqfd; > > > VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); > > > VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); > > > > > > @@ -890,10 +892,21 @@ static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > > > if (vector >= msix_nr_vectors_allocated(dev)) { > > > return 0; > > > } > > > + /* > > > + * if this is recovery and irqfd still in use, means the irqfd was not > > > + * release before and don't need to set up again > > > + */ > > > + if (recovery) { > > > + irqfd = &proxy->vector_irqfd[vector]; > > > + if (irqfd->users != 0) { > > > + return 0; > > > + } > > > + } > > > ret = kvm_virtio_pci_vq_vector_use(proxy, vector); > > > if (ret < 0) { > > > goto undo; > > > } > > > + > > > /* > > > * If guest supports masking, set up irqfd now. > > > * Otherwise, delay until unmasked in the frontend. > > > @@ -932,14 +945,14 @@ static int kvm_virtio_pci_vector_vq_use(VirtIOPCIProxy *proxy, int nvqs) > > > if (!virtio_queue_get_num(vdev, queue_no)) { > > > return -1; > > > } > > > - ret = kvm_virtio_pci_vector_use_one(proxy, queue_no); > > > + ret = kvm_virtio_pci_vector_use_one(proxy, queue_no, false); > > > } > > > return ret; > > > } > > > > > > static int kvm_virtio_pci_vector_config_use(VirtIOPCIProxy *proxy) > > > { > > > - return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX); > > > + return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, false); > > > } > > > > > > static void kvm_virtio_pci_vector_release_one(VirtIOPCIProxy *proxy, > > > @@ -1570,7 +1583,13 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, > > > } else { > > > val = VIRTIO_NO_VECTOR; > > > } > > > + vector = vdev->config_vector; > > > vdev->config_vector = val; > > > + /*check if the vector need to recovery*/ > > > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > > > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > > > + kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, true); > > > + } > > > > This looks too tricky. > > > > Think hard of this. I think it's better to split this into two parts: > > > > 1) a series that disables config irqfd for vhost-net, this series > > needs to be backported to -stable which needs to be conservative. It > > looks more like your V1, but let's add a boolean for pci proxy. > > I don't get it. Looks like a huge change to do in stable. > All as a replacement to a small 20 line patch? For example, this patch needs more tweak so it won't be that tiny: 1) needs to check if we can use guest notifiers (irqfd) 2) the switching from X to NO_VECTOR might need kvm_virtio_pci_vq_vector_release() > > Generally I think irqfd is best used everywhere. Only when msix and kvm are both enabled. > > > > 2) a series that deal with the msix vector configuration after > > driver_ok, we probably need some refactoring to do per vq use instead > > of the current loop in DRIVER_OK > > > > Does this make sense? > > > > Thanks > > > Not really let's fix the bug for starters, refactoring can be done later > as appropriate. This is exactly my point. Avoiding that for non vDPA device seems to be easier or maybe I was wrong. Thanks > > > > break; > > > case VIRTIO_PCI_COMMON_STATUS: > > > if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { > > > @@ -1611,6 +1630,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, > > > val = VIRTIO_NO_VECTOR; > > > } > > > virtio_queue_set_vector(vdev, vdev->queue_sel, val); > > > + > > > + /*check if the vector need to recovery*/ > > > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > > > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > > > + kvm_virtio_pci_vector_use_one(proxy, vdev->queue_sel, true); > > > + } > > > break; > > > case VIRTIO_PCI_COMMON_Q_ENABLE: > > > if (val == 1) { > > > -- > > > 2.43.0 > > > >
On Sun, Apr 7, 2024 at 3:00 PM Cindy Lu <lulu@redhat.com> wrote: > > On Sun, Apr 7, 2024 at 12:20 PM Jason Wang <jasowang@redhat.com> wrote: > > > > On Tue, Apr 2, 2024 at 11:02 PM Cindy Lu <lulu@redhat.com> wrote: > > > > > > When the guest calls virtio_stop and then virtio_reset, > > > > Guests could not call those functions directly, it is triggered by for > > example writing to some of the registers like reset or others. > > > sure , Will fix this > > > the vector will change > > > to VIRTIO_NO_VECTOR and the IRQFD for this vector will be released. After that > > > If you want to change the vector back, > > > > What do you mean by "change the vector back"? Something like > > > > assign VIRTIO_MSI_NO_VECTOR to vector 0 > > assign X to vector 0 > > > yes, the process is something like > .... > set config_vector = VIRTIO_MSI_NO_VECTOR > ... > set config_vector = 0 > > And I guess what you meant is to configure the vector after DRIVER_OK. > > > > > > > > it will cause a crash. > > > > > > To fix this, we need to call the function "kvm_virtio_pci_vector_use_one()" > > > when the vector changes back from VIRTIO_NO_VECTOR > > > > > > Signed-off-by: Cindy Lu <lulu@redhat.com> > > > --- > > > hw/virtio/virtio-pci.c | 31 ++++++++++++++++++++++++++++--- > > > 1 file changed, 28 insertions(+), 3 deletions(-) > > > > > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > > > index e433879542..45f3ab38c3 100644 > > > --- a/hw/virtio/virtio-pci.c > > > +++ b/hw/virtio/virtio-pci.c > > > @@ -874,12 +874,14 @@ static int virtio_pci_get_notifier(VirtIOPCIProxy *proxy, int queue_no, > > > return 0; > > > } > > > > > > -static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > > > +static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no, > > > + bool recovery) > > > { > > > unsigned int vector; > > > int ret; > > > EventNotifier *n; > > > PCIDevice *dev = &proxy->pci_dev; > > > + VirtIOIRQFD *irqfd; > > > VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); > > > VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); > > > > > > @@ -890,10 +892,21 @@ static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > > > if (vector >= msix_nr_vectors_allocated(dev)) { > > > return 0; > > > } > > > + /* > > > + * if this is recovery and irqfd still in use, means the irqfd was not > > > + * release before and don't need to set up again > > > + */ > > > + if (recovery) { > > > + irqfd = &proxy->vector_irqfd[vector]; > > > + if (irqfd->users != 0) { > > > + return 0; > > > + } > > > + } > > > ret = kvm_virtio_pci_vq_vector_use(proxy, vector); > > > if (ret < 0) { > > > goto undo; > > > } > > > + > > > /* > > > * If guest supports masking, set up irqfd now. > > > * Otherwise, delay until unmasked in the frontend. > > > @@ -932,14 +945,14 @@ static int kvm_virtio_pci_vector_vq_use(VirtIOPCIProxy *proxy, int nvqs) > > > if (!virtio_queue_get_num(vdev, queue_no)) { > > > return -1; > > > } > > > - ret = kvm_virtio_pci_vector_use_one(proxy, queue_no); > > > + ret = kvm_virtio_pci_vector_use_one(proxy, queue_no, false); > > > } > > > return ret; > > > } > > > > > > static int kvm_virtio_pci_vector_config_use(VirtIOPCIProxy *proxy) > > > { > > > - return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX); > > > + return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, false); > > > } > > > > > > static void kvm_virtio_pci_vector_release_one(VirtIOPCIProxy *proxy, > > > @@ -1570,7 +1583,13 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, > > > } else { > > > val = VIRTIO_NO_VECTOR; > > > } > > > + vector = vdev->config_vector; > > > vdev->config_vector = val; > > > + /*check if the vector need to recovery*/ > > > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > > > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > > > + kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, true); > > > + } > > > > This looks too tricky. > > > > Think hard of this. I think it's better to split this into two parts: > > > > 1) a series that disables config irqfd for vhost-net, this series > > needs to be backported to -stable which needs to be conservative. It > > looks more like your V1, but let's add a boolean for pci proxy. > sure, I wll try this > > > 2) a series that deal with the msix vector configuration after > > driver_ok, we probably need some refactoring to do per vq use instead > > of the current loop in DRIVER_OK > > > Sorry I didn't get what you mean , Do you mean we need to move the check > to inside kvm_virtio_pci_vector_vq_use()？ > Thanks > cindy I meant try to do use/release during mmio write instead of start. Note that Michael seems to prefer the approach of this patch. Let's fix the comment I gave in another thread and see. Thanks > > Does this make sense? > > > > Thanks > > > > > break; > > > case VIRTIO_PCI_COMMON_STATUS: > > > if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { > > > @@ -1611,6 +1630,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, > > > val = VIRTIO_NO_VECTOR; > > > } > > > virtio_queue_set_vector(vdev, vdev->queue_sel, val); > > > + > > > + /*check if the vector need to recovery*/ > > > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > > > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > > > + kvm_virtio_pci_vector_use_one(proxy, vdev->queue_sel, true); > > > + } > > > break; > > > case VIRTIO_PCI_COMMON_Q_ENABLE: > > > if (val == 1) { > > > -- > > > 2.43.0 > > > > > >
On Mon, Apr 8, 2024 at 12:59 PM Jason Wang <jasowang@redhat.com> wrote: > > On Sun, Apr 7, 2024 at 3:00 PM Cindy Lu <lulu@redhat.com> wrote: > > > > On Sun, Apr 7, 2024 at 12:20 PM Jason Wang <jasowang@redhat.com> wrote: > > > > > > On Tue, Apr 2, 2024 at 11:02 PM Cindy Lu <lulu@redhat.com> wrote: > > > > > > > > When the guest calls virtio_stop and then virtio_reset, > > > > > > Guests could not call those functions directly, it is triggered by for > > > example writing to some of the registers like reset or others. > > > > > sure , Will fix this > > > > the vector will change > > > > to VIRTIO_NO_VECTOR and the IRQFD for this vector will be released. After that > > > > If you want to change the vector back, > > > > > > What do you mean by "change the vector back"? Something like > > > > > > assign VIRTIO_MSI_NO_VECTOR to vector 0 > > > assign X to vector 0 > > > > > yes, the process is something like > > .... > > set config_vector = VIRTIO_MSI_NO_VECTOR > > ... > > set config_vector = 0 > > > And I guess what you meant is to configure the vector after DRIVER_OK. > > > > > > > > > > > > it will cause a crash. > > > > > > > > To fix this, we need to call the function "kvm_virtio_pci_vector_use_one()" > > > > when the vector changes back from VIRTIO_NO_VECTOR > > > > > > > > Signed-off-by: Cindy Lu <lulu@redhat.com> > > > > --- > > > > hw/virtio/virtio-pci.c | 31 ++++++++++++++++++++++++++++--- > > > > 1 file changed, 28 insertions(+), 3 deletions(-) > > > > > > > > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > > > > index e433879542..45f3ab38c3 100644 > > > > --- a/hw/virtio/virtio-pci.c > > > > +++ b/hw/virtio/virtio-pci.c > > > > @@ -874,12 +874,14 @@ static int virtio_pci_get_notifier(VirtIOPCIProxy *proxy, int queue_no, > > > > return 0; > > > > } > > > > > > > > -static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > > > > +static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no, > > > > + bool recovery) > > > > { > > > > unsigned int vector; > > > > int ret; > > > > EventNotifier *n; > > > > PCIDevice *dev = &proxy->pci_dev; > > > > + VirtIOIRQFD *irqfd; > > > > VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); > > > > VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); > > > > > > > > @@ -890,10 +892,21 @@ static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) > > > > if (vector >= msix_nr_vectors_allocated(dev)) { > > > > return 0; > > > > } > > > > + /* > > > > + * if this is recovery and irqfd still in use, means the irqfd was not > > > > + * release before and don't need to set up again > > > > + */ > > > > + if (recovery) { > > > > + irqfd = &proxy->vector_irqfd[vector]; > > > > + if (irqfd->users != 0) { > > > > + return 0; > > > > + } > > > > + } > > > > ret = kvm_virtio_pci_vq_vector_use(proxy, vector); > > > > if (ret < 0) { > > > > goto undo; > > > > } > > > > + > > > > /* > > > > * If guest supports masking, set up irqfd now. > > > > * Otherwise, delay until unmasked in the frontend. > > > > @@ -932,14 +945,14 @@ static int kvm_virtio_pci_vector_vq_use(VirtIOPCIProxy *proxy, int nvqs) > > > > if (!virtio_queue_get_num(vdev, queue_no)) { > > > > return -1; > > > > } > > > > - ret = kvm_virtio_pci_vector_use_one(proxy, queue_no); > > > > + ret = kvm_virtio_pci_vector_use_one(proxy, queue_no, false); > > > > } > > > > return ret; > > > > } > > > > > > > > static int kvm_virtio_pci_vector_config_use(VirtIOPCIProxy *proxy) > > > > { > > > > - return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX); > > > > + return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, false); > > > > } > > > > > > > > static void kvm_virtio_pci_vector_release_one(VirtIOPCIProxy *proxy, > > > > @@ -1570,7 +1583,13 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, > > > > } else { > > > > val = VIRTIO_NO_VECTOR; > > > > } > > > > + vector = vdev->config_vector; > > > > vdev->config_vector = val; > > > > + /*check if the vector need to recovery*/ > > > > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > > > > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > > > > + kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, true); > > > > + } > > > > > > This looks too tricky. > > > > > > Think hard of this. I think it's better to split this into two parts: > > > > > > 1) a series that disables config irqfd for vhost-net, this series > > > needs to be backported to -stable which needs to be conservative. It > > > looks more like your V1, but let's add a boolean for pci proxy. > > sure, I wll try this > > > > > 2) a series that deal with the msix vector configuration after > > > driver_ok, we probably need some refactoring to do per vq use instead > > > of the current loop in DRIVER_OK > > > > > Sorry I didn't get what you mean , Do you mean we need to move the check > > to inside kvm_virtio_pci_vector_vq_use()？ > > Thanks > > cindy > > I meant try to do use/release during mmio write instead of start. > > Note that Michael seems to prefer the approach of this patch. Let's > fix the comment I gave in another thread and see. > > Thanks > sure, got ot. I will try this thanks cindy > > > Does this make sense? > > > > > > Thanks > > > > > > > break; > > > > case VIRTIO_PCI_COMMON_STATUS: > > > > if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { > > > > @@ -1611,6 +1630,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, > > > > val = VIRTIO_NO_VECTOR; > > > > } > > > > virtio_queue_set_vector(vdev, vdev->queue_sel, val); > > > > + > > > > + /*check if the vector need to recovery*/ > > > > + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && > > > > + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { > > > > + kvm_virtio_pci_vector_use_one(proxy, vdev->queue_sel, true); > > > > + } > > > > break; > > > > case VIRTIO_PCI_COMMON_Q_ENABLE: > > > > if (val == 1) { > > > > -- > > > > 2.43.0 > > > > > > > > > >
diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index e433879542..45f3ab38c3 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -874,12 +874,14 @@ static int virtio_pci_get_notifier(VirtIOPCIProxy *proxy, int queue_no, return 0; } -static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) +static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no, + bool recovery) { unsigned int vector; int ret; EventNotifier *n; PCIDevice *dev = &proxy->pci_dev; + VirtIOIRQFD *irqfd; VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev); @@ -890,10 +892,21 @@ static int kvm_virtio_pci_vector_use_one(VirtIOPCIProxy *proxy, int queue_no) if (vector >= msix_nr_vectors_allocated(dev)) { return 0; } + /* + * if this is recovery and irqfd still in use, means the irqfd was not + * release before and don't need to set up again + */ + if (recovery) { + irqfd = &proxy->vector_irqfd[vector]; + if (irqfd->users != 0) { + return 0; + } + } ret = kvm_virtio_pci_vq_vector_use(proxy, vector); if (ret < 0) { goto undo; } + /* * If guest supports masking, set up irqfd now. * Otherwise, delay until unmasked in the frontend. @@ -932,14 +945,14 @@ static int kvm_virtio_pci_vector_vq_use(VirtIOPCIProxy *proxy, int nvqs) if (!virtio_queue_get_num(vdev, queue_no)) { return -1; } - ret = kvm_virtio_pci_vector_use_one(proxy, queue_no); + ret = kvm_virtio_pci_vector_use_one(proxy, queue_no, false); } return ret; } static int kvm_virtio_pci_vector_config_use(VirtIOPCIProxy *proxy) { - return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX); + return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, false); } static void kvm_virtio_pci_vector_release_one(VirtIOPCIProxy *proxy, @@ -1570,7 +1583,13 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, } else { val = VIRTIO_NO_VECTOR; } + vector = vdev->config_vector; vdev->config_vector = val; + /*check if the vector need to recovery*/ + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { + kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX, true); + } break; case VIRTIO_PCI_COMMON_STATUS: if (!(val & VIRTIO_CONFIG_S_DRIVER_OK)) { @@ -1611,6 +1630,12 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, val = VIRTIO_NO_VECTOR; } virtio_queue_set_vector(vdev, vdev->queue_sel, val); + + /*check if the vector need to recovery*/ + if ((val != VIRTIO_NO_VECTOR) && (vector == VIRTIO_NO_VECTOR) && + (vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { + kvm_virtio_pci_vector_use_one(proxy, vdev->queue_sel, true); + } break; case VIRTIO_PCI_COMMON_Q_ENABLE: if (val == 1) {
When the guest calls virtio_stop and then virtio_reset, the vector will change to VIRTIO_NO_VECTOR and the IRQFD for this vector will be released. After that If you want to change the vector back, it will cause a crash. To fix this, we need to call the function "kvm_virtio_pci_vector_use_one()" when the vector changes back from VIRTIO_NO_VECTOR Signed-off-by: Cindy Lu <lulu@redhat.com> --- hw/virtio/virtio-pci.c | 31 ++++++++++++++++++++++++++++--- 1 file changed, 28 insertions(+), 3 deletions(-)