| Message ID | 1464472878-27176-7-git-send-email-okaya@codeaurora.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Le 29/05/2016 à 00:01, Sinan Kaya a écrit : > The code was allowing platform devices to be used without a supporting > VFIO reset driver. The hardware can be left in some inconsistent state > after a guest machine abort. > > The reset driver will put the hardware back to safe state and disable > interrupts before returning the control back to the host machine. > > Adding a new reset_required kernel module option to AMBA and platform > VFIO drivers with a default value of true. > > New requirements are: > 1. A reset function needs to be implemented by the corresponding driver > via DT/ACPI. > 2. The reset function needs to be discovered via DT/ACPI. > > The probe of the driver will fail if any of the above conditions are > not satisfied. > > Signed-off-by: Sinan Kaya <okaya@codeaurora.org> > --- > drivers/vfio/platform/vfio_amba.c | 5 +++++ > drivers/vfio/platform/vfio_platform.c | 5 +++++ > drivers/vfio/platform/vfio_platform_common.c | 14 +++++++++++--- > drivers/vfio/platform/vfio_platform_private.h | 1 + > 4 files changed, 22 insertions(+), 3 deletions(-) > > diff --git a/drivers/vfio/platform/vfio_amba.c b/drivers/vfio/platform/vfio_amba.c > index a66479b..7585902 100644 > --- a/drivers/vfio/platform/vfio_amba.c > +++ b/drivers/vfio/platform/vfio_amba.c > @@ -23,6 +23,10 @@ > #define DRIVER_AUTHOR "Antonios Motakis <a.motakis@virtualopensystems.com>" > #define DRIVER_DESC "VFIO for AMBA devices - User Level meta-driver" > > +static bool reset_required = true; > +module_param(reset_required, bool, 0644); > +MODULE_PARM_DESC(reset_required, "override reset requirement (default: 1)"); > + > /* probing devices from the AMBA bus */ > > static struct resource *get_amba_resource(struct vfio_platform_device *vdev, > @@ -68,6 +72,7 @@ static int vfio_amba_probe(struct amba_device *adev, const struct amba_id *id) > vdev->get_resource = get_amba_resource; > vdev->get_irq = get_amba_irq; > vdev->parent_module = THIS_MODULE; > + vdev->reset_required = reset_required; > > ret = vfio_platform_probe_common(vdev, &adev->dev); > if (ret) { > diff --git a/drivers/vfio/platform/vfio_platform.c b/drivers/vfio/platform/vfio_platform.c > index b1cc3a7..ef89146 100644 > --- a/drivers/vfio/platform/vfio_platform.c > +++ b/drivers/vfio/platform/vfio_platform.c > @@ -23,6 +23,10 @@ > #define DRIVER_AUTHOR "Antonios Motakis <a.motakis@virtualopensystems.com>" > #define DRIVER_DESC "VFIO for platform devices - User Level meta-driver" > > +static bool reset_required = true; > +module_param(reset_required, bool, 0644); > +MODULE_PARM_DESC(reset_required, "override reset requirement (default: 1)"); > + > /* probing devices from the linux platform bus */ > > static struct resource *get_platform_resource(struct vfio_platform_device *vdev, > @@ -66,6 +70,7 @@ static int vfio_platform_probe(struct platform_device *pdev) > vdev->get_resource = get_platform_resource; > vdev->get_irq = get_platform_irq; > vdev->parent_module = THIS_MODULE; > + vdev->reset_required = reset_required; > > ret = vfio_platform_probe_common(vdev, &pdev->dev); > if (ret) > diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c > index 0ea8c26..e87ceab 100644 > --- a/drivers/vfio/platform/vfio_platform_common.c > +++ b/drivers/vfio/platform/vfio_platform_common.c > @@ -128,10 +128,10 @@ static bool vfio_platform_has_reset(struct vfio_platform_device *vdev) > return vdev->of_reset ? true : false; > } > > -static void vfio_platform_get_reset(struct vfio_platform_device *vdev) > +static int vfio_platform_get_reset(struct vfio_platform_device *vdev) > { > if (vdev->acpihid) > - return; > + return vfio_platform_acpi_has_reset(vdev) ? 0 : -ENOENT; > > vdev->of_reset = vfio_platform_lookup_reset(vdev->compat, > &vdev->reset_module); > @@ -140,6 +140,8 @@ static void vfio_platform_get_reset(struct vfio_platform_device *vdev) > vdev->of_reset = vfio_platform_lookup_reset(vdev->compat, > &vdev->reset_module); > } > + > + return vdev->of_reset ? 0 : -ENOENT; > } > > static void vfio_platform_put_reset(struct vfio_platform_device *vdev) > @@ -675,7 +677,13 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev, > return ret; > } > > - vfio_platform_get_reset(vdev); > + ret = vfio_platform_get_reset(vdev); > + if (ret && vdev->reset_required) { > + pr_err("vfio: no reset function found for device %s\n", > + vdev->name); > + iommu_group_put(group); > + return ret; nit: in case you respin you can factorize the group put and return ret in a goto label (since also used above). Besides Reviewed-by: Eric Auger <eric.auger@redhat.com> Thanks Eric > + } > > mutex_init(&vdev->igate); > > diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h > index ba9e4f8..68fbc00 100644 > --- a/drivers/vfio/platform/vfio_platform_private.h > +++ b/drivers/vfio/platform/vfio_platform_private.h > @@ -50,6 +50,7 @@ struct vfio_platform_region { > }; > > struct vfio_platform_device { > + bool reset_required; > struct vfio_platform_region *regions; > u32 num_regions; > struct vfio_platform_irq *irqs; > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 6/7/2016 3:59 PM, Auger Eric wrote: >> - vfio_platform_get_reset(vdev); >> > + ret = vfio_platform_get_reset(vdev); >> > + if (ret && vdev->reset_required) { >> > + pr_err("vfio: no reset function found for device %s\n", >> > + vdev->name); >> > + iommu_group_put(group); >> > + return ret; > nit: in case you respin you can factorize the group put and return ret in a goto label > (since also used above). > > Besides Reviewed-by: Eric Auger <eric.auger@redhat.com> thanks, done. I'll respin with your request.
diff --git a/drivers/vfio/platform/vfio_amba.c b/drivers/vfio/platform/vfio_amba.c index a66479b..7585902 100644 --- a/drivers/vfio/platform/vfio_amba.c +++ b/drivers/vfio/platform/vfio_amba.c @@ -23,6 +23,10 @@ #define DRIVER_AUTHOR "Antonios Motakis <a.motakis@virtualopensystems.com>" #define DRIVER_DESC "VFIO for AMBA devices - User Level meta-driver" +static bool reset_required = true; +module_param(reset_required, bool, 0644); +MODULE_PARM_DESC(reset_required, "override reset requirement (default: 1)"); + /* probing devices from the AMBA bus */ static struct resource *get_amba_resource(struct vfio_platform_device *vdev, @@ -68,6 +72,7 @@ static int vfio_amba_probe(struct amba_device *adev, const struct amba_id *id) vdev->get_resource = get_amba_resource; vdev->get_irq = get_amba_irq; vdev->parent_module = THIS_MODULE; + vdev->reset_required = reset_required; ret = vfio_platform_probe_common(vdev, &adev->dev); if (ret) { diff --git a/drivers/vfio/platform/vfio_platform.c b/drivers/vfio/platform/vfio_platform.c index b1cc3a7..ef89146 100644 --- a/drivers/vfio/platform/vfio_platform.c +++ b/drivers/vfio/platform/vfio_platform.c @@ -23,6 +23,10 @@ #define DRIVER_AUTHOR "Antonios Motakis <a.motakis@virtualopensystems.com>" #define DRIVER_DESC "VFIO for platform devices - User Level meta-driver" +static bool reset_required = true; +module_param(reset_required, bool, 0644); +MODULE_PARM_DESC(reset_required, "override reset requirement (default: 1)"); + /* probing devices from the linux platform bus */ static struct resource *get_platform_resource(struct vfio_platform_device *vdev, @@ -66,6 +70,7 @@ static int vfio_platform_probe(struct platform_device *pdev) vdev->get_resource = get_platform_resource; vdev->get_irq = get_platform_irq; vdev->parent_module = THIS_MODULE; + vdev->reset_required = reset_required; ret = vfio_platform_probe_common(vdev, &pdev->dev); if (ret) diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c index 0ea8c26..e87ceab 100644 --- a/drivers/vfio/platform/vfio_platform_common.c +++ b/drivers/vfio/platform/vfio_platform_common.c @@ -128,10 +128,10 @@ static bool vfio_platform_has_reset(struct vfio_platform_device *vdev) return vdev->of_reset ? true : false; } -static void vfio_platform_get_reset(struct vfio_platform_device *vdev) +static int vfio_platform_get_reset(struct vfio_platform_device *vdev) { if (vdev->acpihid) - return; + return vfio_platform_acpi_has_reset(vdev) ? 0 : -ENOENT; vdev->of_reset = vfio_platform_lookup_reset(vdev->compat, &vdev->reset_module); @@ -140,6 +140,8 @@ static void vfio_platform_get_reset(struct vfio_platform_device *vdev) vdev->of_reset = vfio_platform_lookup_reset(vdev->compat, &vdev->reset_module); } + + return vdev->of_reset ? 0 : -ENOENT; } static void vfio_platform_put_reset(struct vfio_platform_device *vdev) @@ -675,7 +677,13 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev, return ret; } - vfio_platform_get_reset(vdev); + ret = vfio_platform_get_reset(vdev); + if (ret && vdev->reset_required) { + pr_err("vfio: no reset function found for device %s\n", + vdev->name); + iommu_group_put(group); + return ret; + } mutex_init(&vdev->igate); diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h index ba9e4f8..68fbc00 100644 --- a/drivers/vfio/platform/vfio_platform_private.h +++ b/drivers/vfio/platform/vfio_platform_private.h @@ -50,6 +50,7 @@ struct vfio_platform_region { }; struct vfio_platform_device { + bool reset_required; struct vfio_platform_region *regions; u32 num_regions; struct vfio_platform_irq *irqs;
The code was allowing platform devices to be used without a supporting VFIO reset driver. The hardware can be left in some inconsistent state after a guest machine abort. The reset driver will put the hardware back to safe state and disable interrupts before returning the control back to the host machine. Adding a new reset_required kernel module option to AMBA and platform VFIO drivers with a default value of true. New requirements are: 1. A reset function needs to be implemented by the corresponding driver via DT/ACPI. 2. The reset function needs to be discovered via DT/ACPI. The probe of the driver will fail if any of the above conditions are not satisfied. Signed-off-by: Sinan Kaya <okaya@codeaurora.org> --- drivers/vfio/platform/vfio_amba.c | 5 +++++ drivers/vfio/platform/vfio_platform.c | 5 +++++ drivers/vfio/platform/vfio_platform_common.c | 14 +++++++++++--- drivers/vfio/platform/vfio_platform_private.h | 1 + 4 files changed, 22 insertions(+), 3 deletions(-)