On 24/01/2020 12:02, Stefan Hajnoczi wrote: > On Thu, Jan 23, 2020 at 04:16:58PM +0100, Laurent Vivier wrote: >> The kernel needs sometime to be able to cancel an ongoing command. >> >> For instance, if the virtio-rng device uses the egd backend >> and this backend doesn't provide data, the buffer provided by the >> kernel is kept as long as it is needed. >> >> On the kernel side, a read blocks until the buffer returns from QEMU. >> >> As the read is done with a mutex held, all the hw_random interface >> hangs and we cannot switch to another hw_random backend. >> >> So this series adds a control queue to the virtio-rng device to allow >> to flush the virtio-rng input queue to release the kernel mutex and >> to allow to switch to another device. >> >> The kernel side series can be found at: >> >> https://github.com/vivier/linux/commits/virtio-rng-ctrl >> >> Laurent Vivier (2): >> virtio-rng: prepare the introduction of a control queue >> virtio-rng: add a control queue >> >> hw/core/machine.c | 1 + >> hw/virtio/trace-events | 6 ++ >> hw/virtio/virtio-rng.c | 99 ++++++++++++++++++--- >> include/hw/virtio/virtio-rng.h | 5 +- >> include/standard-headers/linux/virtio_rng.h | 14 +++ >> 5 files changed, 111 insertions(+), 14 deletions(-) > > Where can I find the VIRTIO specification for this new virtqueue?
I didn't update the specs. Is https://github.com/oasis-tcs/virtio-spec.git the document to update? Thanks, Laurent
