Re: [PATCH v6 2/9] vfio: Add Error** argument to vfio_devices_dma_logging_start()

["Cédric Le Goater" <clg@redhat.com>]

On 5/15/24 08:53, Eric Auger wrote:
> Hi Cédric,
> On 5/14/24 17:31, Cédric Le Goater wrote:
>> This allows to update the Error argument of the VFIO log_global_start()
>> handler. Errors for container based logging will also be propagated to
>> qemu_savevm_state_setup() when the ram save_setup() handler is executed.
> nit: also now collect & print errors from
> vfio_container_set_dirty_page_tracking()

OK. To avoid resending, I amended the commit log with :

"Also, errors from vfio_container_set_dirty_page_tracking() are now
collected and reported."


Thanks,

C.



>>
>> The vfio_set_migration_error() call becomes redundant in
>> vfio_listener_log_global_start(). Remove it.
>>
>> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
>> Reviewed-by: Avihai Horon <avihaih@nvidia.com>
>> Signed-off-by: Cédric Le Goater <clg@redhat.com>
>> ---
>>
>>   Changes in v6:
>>
>>   - Commit log improvements (Avihai)
>>   
>>   Changes in v5:
>>
>>   - Used error_setg_errno() in vfio_devices_dma_logging_start()
>>   
>>   hw/vfio/common.c | 26 +++++++++++++++-----------
>>   1 file changed, 15 insertions(+), 11 deletions(-)
>>
>> diff --git a/hw/vfio/common.c b/hw/vfio/common.c
>> index 485e53916491f1164d29e739fb7106c0c77df737..b5102f54a6474a50c6366e8fbce23812d55e384e 100644
>> --- a/hw/vfio/common.c
>> +++ b/hw/vfio/common.c
>> @@ -1027,7 +1027,8 @@ static void vfio_device_feature_dma_logging_start_destroy(
>>       g_free(feature);
>>   }
>>   
>> -static int vfio_devices_dma_logging_start(VFIOContainerBase *bcontainer)
>> +static int vfio_devices_dma_logging_start(VFIOContainerBase *bcontainer,
>> +                                          Error **errp)
>>   {
>>       struct vfio_device_feature *feature;
>>       VFIODirtyRanges ranges;
>> @@ -1038,6 +1039,7 @@ static int vfio_devices_dma_logging_start(VFIOContainerBase *bcontainer)
>>       feature = vfio_device_feature_dma_logging_start_create(bcontainer,
>>                                                              &ranges);
>>       if (!feature) {
>> +        error_setg_errno(errp, errno, "Failed to prepare DMA logging");
>>           return -errno;
>>       }
>>   
>> @@ -1049,8 +1051,8 @@ static int vfio_devices_dma_logging_start(VFIOContainerBase *bcontainer)
>>           ret = ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature);
>>           if (ret) {
>>               ret = -errno;
>> -            error_report("%s: Failed to start DMA logging, err %d (%s)",
>> -                         vbasedev->name, ret, strerror(errno));
>> +            error_setg_errno(errp, errno, "%s: Failed to start DMA logging",
>> +                             vbasedev->name);
>>               goto out;
>>           }
>>           vbasedev->dirty_tracking = true;
>> @@ -1069,20 +1071,19 @@ out:
>>   static bool vfio_listener_log_global_start(MemoryListener *listener,
>>                                              Error **errp)
>>   {
>> +    ERRP_GUARD();
>>       VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
>>                                                    listener);
>>       int ret;
>>   
>>       if (vfio_devices_all_device_dirty_tracking(bcontainer)) {
>> -        ret = vfio_devices_dma_logging_start(bcontainer);
>> +        ret = vfio_devices_dma_logging_start(bcontainer, errp);
>>       } else {
>> -        ret = vfio_container_set_dirty_page_tracking(bcontainer, true, NULL);
>> +        ret = vfio_container_set_dirty_page_tracking(bcontainer, true, errp);
>>       }
>>   
>>       if (ret) {
>> -        error_report("vfio: Could not start dirty page tracking, err: %d (%s)",
>> -                     ret, strerror(-ret));
>> -        vfio_set_migration_error(ret);
>> +        error_prepend(errp, "vfio: Could not start dirty page tracking - ");
>>       }
>>       return !ret;
>>   }
>> @@ -1091,17 +1092,20 @@ static void vfio_listener_log_global_stop(MemoryListener *listener)
>>   {
>>       VFIOContainerBase *bcontainer = container_of(listener, VFIOContainerBase,
>>                                                    listener);
>> +    Error *local_err = NULL;
>>       int ret = 0;
>>   
>>       if (vfio_devices_all_device_dirty_tracking(bcontainer)) {
>>           vfio_devices_dma_logging_stop(bcontainer);
>>       } else {
>> -        ret = vfio_container_set_dirty_page_tracking(bcontainer, false, NULL);
>> +        ret = vfio_container_set_dirty_page_tracking(bcontainer, false,
>> +                                                     &local_err);
>>       }
>>   
>>       if (ret) {
>> -        error_report("vfio: Could not stop dirty page tracking, err: %d (%s)",
>> -                     ret, strerror(-ret));
>> +        error_prepend(&local_err,
>> +                      "vfio: Could not stop dirty page tracking - ");
>> +        error_report_err(local_err);
>>           vfio_set_migration_error(ret);
>>       }
>>   }
> 
> Reviewed-by: Eric Auger <eric.auger@redhat.com>
> 
> Eric
>