From 483baf4c668fbd2da76e6948576e13eded1c54ec Mon Sep 17 00:00:00 2001 From: Shenming Lu Date: Wed, 10 Mar 2021 11:02:31 +0800 Subject: [PATCH 1/3] vfio: Move the saving of the config space to the right place in VFIO migration On ARM64 the VFIO SET_IRQS ioctl is dependent on the VM interrupt setup, if the restoring of the VFIO PCI device config space is before the VGIC, an error might occur in the kernel. So we move the saving of the config space to the non-iterable process, thus it will be called after the VGIC according to their priorities. As for the possible dependence of the device specific migration data on it's config space, we can let the vendor driver to include any config info it needs in its own data stream. Signed-off-by: Shenming Lu Reviewed-by: Kirti Wankhede Message-Id: <20210310030233.1133-2-lushenming@huawei.com> Signed-off-by: Alex Williamson --- hw/vfio/migration.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c index b77c66557e..ea36ae5225 100644 --- a/hw/vfio/migration.c +++ b/hw/vfio/migration.c @@ -575,11 +575,6 @@ static int vfio_save_complete_precopy(QEMUFile *f, void *opaque) return ret; } - ret = vfio_save_device_config_state(f, opaque); - if (ret) { - return ret; - } - ret = vfio_update_pending(vbasedev); if (ret) { return ret; @@ -620,6 +615,19 @@ static int vfio_save_complete_precopy(QEMUFile *f, void *opaque) return ret; } +static void vfio_save_state(QEMUFile *f, void *opaque) +{ + VFIODevice *vbasedev = opaque; + int ret; + + ret = vfio_save_device_config_state(f, opaque); + if (ret) { + error_report("%s: Failed to save device config space", + vbasedev->name); + qemu_file_set_error(f, ret); + } +} + static int vfio_load_setup(QEMUFile *f, void *opaque) { VFIODevice *vbasedev = opaque; @@ -670,11 +678,7 @@ static int vfio_load_state(QEMUFile *f, void *opaque, int version_id) switch (data) { case VFIO_MIG_FLAG_DEV_CONFIG_STATE: { - ret = vfio_load_device_config_state(f, opaque); - if (ret) { - return ret; - } - break; + return vfio_load_device_config_state(f, opaque); } case VFIO_MIG_FLAG_DEV_SETUP_STATE: { @@ -720,6 +724,7 @@ static SaveVMHandlers savevm_vfio_handlers = { .save_live_pending = vfio_save_pending, .save_live_iterate = vfio_save_iterate, .save_live_complete_precopy = vfio_save_complete_precopy, + .save_state = vfio_save_state, .load_setup = vfio_load_setup, .load_cleanup = vfio_load_cleanup, .load_state = vfio_load_state, -- Gitee From b9d74bcf6aefe8ab607439ad1c518a453053ccee Mon Sep 17 00:00:00 2001 From: Shenming Lu Date: Wed, 10 Mar 2021 11:02:32 +0800 Subject: [PATCH 2/3] vfio: Set the priority of the VFIO VM state change handler explicitly In the VFIO VM state change handler when stopping the VM, the _RUNNING bit in device_state is cleared which makes the VFIO device stop, including no longer generating interrupts. Then we can save the pending states of all interrupts in the GIC VM state change handler (on ARM). So we have to set the priority of the VFIO VM state change handler explicitly (like virtio devices) to ensure it is called before the GIC's in saving. Signed-off-by: Shenming Lu Reviewed-by: Kirti Wankhede Reviewed-by: Cornelia Huck Message-Id: <20210310030233.1133-3-lushenming@huawei.com> Signed-off-by: Alex Williamson --- hw/vfio/migration.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c index ea36ae5225..1a97784486 100644 --- a/hw/vfio/migration.c +++ b/hw/vfio/migration.c @@ -862,7 +862,8 @@ static int vfio_migration_init(VFIODevice *vbasedev, register_savevm_live(id, VMSTATE_INSTANCE_ID_ANY, 1, &savevm_vfio_handlers, vbasedev); - migration->vm_state = qemu_add_vm_change_state_handler(vfio_vmstate_change, + migration->vm_state = qdev_add_vm_change_state_handler(vbasedev->dev, + vfio_vmstate_change, vbasedev); migration->migration_state.notify = vfio_migration_state_notifier; add_migration_state_change_notifier(&migration->migration_state); -- Gitee From 8113fdcf0c1383ae5b9542563656bea3753d834e Mon Sep 17 00:00:00 2001 From: Shenming Lu Date: Wed, 10 Mar 2021 11:02:33 +0800 Subject: [PATCH 3/3] vfio: Avoid disabling and enabling vectors repeatedly in VFIO migration In VFIO migration resume phase and some guest startups, there are already unmasked vectors in the vector table when calling vfio_msix_enable(). So in order to avoid inefficiently disabling and enabling vectors repeatedly, let's allocate all needed vectors first and then enable these unmasked vectors one by one without disabling. Signed-off-by: Shenming Lu Message-Id: <20210310030233.1133-4-lushenming@huawei.com> Signed-off-by: Alex Williamson --- hw/vfio/pci.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c index a637c35e7a..da7c740bce 100644 --- a/hw/vfio/pci.c +++ b/hw/vfio/pci.c @@ -563,6 +563,9 @@ static void vfio_msix_vector_release(PCIDevice *pdev, unsigned int nr) static void vfio_msix_enable(VFIOPCIDevice *vdev) { + PCIDevice *pdev = &vdev->pdev; + unsigned int nr, max_vec = 0; + vfio_disable_interrupts(vdev); vdev->msi_vectors = g_new0(VFIOMSIVector, vdev->msix->entries); @@ -581,11 +584,22 @@ static void vfio_msix_enable(VFIOPCIDevice *vdev) * triggering to userspace, then immediately release the vector, leaving * the physical device with no vectors enabled, but MSI-X enabled, just * like the guest view. + * If there are already unmasked vectors (in migration resume phase and + * some guest startups) which will be enabled soon, we can allocate all + * of them here to avoid inefficiently disabling and enabling vectors + * repeatedly later. */ - vfio_msix_vector_do_use(&vdev->pdev, 0, NULL, NULL); - vfio_msix_vector_release(&vdev->pdev, 0); + if (!pdev->msix_function_masked) { + for (nr = 0; nr < msix_nr_vectors_allocated(pdev); nr++) { + if (!msix_is_masked(pdev, nr)) { + max_vec = nr; + } + } + } + vfio_msix_vector_do_use(pdev, max_vec, NULL, NULL); + vfio_msix_vector_release(pdev, max_vec); - if (msix_set_vector_notifiers(&vdev->pdev, vfio_msix_vector_use, + if (msix_set_vector_notifiers(pdev, vfio_msix_vector_use, vfio_msix_vector_release, NULL)) { error_report("vfio: msix_set_vector_notifiers failed"); } -- Gitee