On 23/07/20, Jorge Ramirez-Ortiz wrote:
The current code waits for data to be available before attempting a second read. However the second read would not be executed as the while loop exits.
This fix does not wait if all data has been read and reads a second time if only partial data was retrieved on the first read.
This fix also does not attempt to read if not data is requested.
Signed-off-by: Jorge Ramirez-Ortiz jorge@foundries.io
v2: tidy up the while loop to avoid reading when no data is requested
drivers/char/hw_random/optee-rng.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/char/hw_random/optee-rng.c b/drivers/char/hw_random/optee-rng.c index 5bc4700c4dae..a99d82949981 100644 --- a/drivers/char/hw_random/optee-rng.c +++ b/drivers/char/hw_random/optee-rng.c @@ -122,14 +122,14 @@ static int optee_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait) if (max > MAX_ENTROPY_REQ_SZ) max = MAX_ENTROPY_REQ_SZ;
- while (read == 0) {
- while (read < max) { rng_size = get_optee_rng_data(pvt_data, data, (max - read));
data += rng_size; read += rng_size; if (wait && pvt_data->data_rate) {
if (timeout-- == 0)
if ((timeout-- == 0) || (read == max)) return read; msleep((1000 * (max - read)) / pvt_data->data_rate);
any comments please?