hwrng core uses two buffers that can be mixed in the virtio-rng queue. This series fixes the problem by adding an internal buffer in virtio-rng. Once the internal buffer is added, we can fix two other problems: - to be able to release the driver without waiting the device releases the buffer - actually returns some data when wait=0 as we can have some already available data It also tries to improve the performance by always having a buffer in the queue of the device. v2: fixes issue reported by syzbot+b86736b5935e0d25b446@xxxxxxxxxxxxxxxxxxxxxxxxx by reseting data_idx to 0 when the buffer is submitted not when it is received as the consumer checks for data_avail, not only for the completion. Laurent Vivier (4): hwrng: virtio - add an internal buffer hwrng: virtio - don't wait on cleanup hwrng: virtio - don't waste entropy hwrng: virtio - always add a pending request drivers/char/hw_random/virtio-rng.c | 86 ++++++++++++++++++++++------- 1 file changed, 65 insertions(+), 21 deletions(-) -- 2.31.1
