On 16/10/2016 12:02, Stefan Hajnoczi wrote:
> On Thu, Oct 13, 2016 at 07:34:06PM +0200, Paolo Bonzini wrote:
>> +static void backup_drain(BlockJob *job)
>> +{
>> +BackupBlockJob *s = container_of(job, BackupBlockJob, common);
>> +
>> +/* Need to keep a reference in case blk_drain
On Thu, Oct 13, 2016 at 07:34:06PM +0200, Paolo Bonzini wrote:
> +static void backup_drain(BlockJob *job)
> +{
> +BackupBlockJob *s = container_of(job, BackupBlockJob, common);
> +
> +/* Need to keep a reference in case blk_drain triggers execution
> + * of backup_complete...
> +
This is required to decouple block jobs from running in an
AioContext. With multiqueue block devices, a BlockDriverState
does not really belong to a single AioContext.
The solution is to first wait until all I/O operations are
complete; then loop in the main thread for the block job to
complete
