Hi Guenter,
On Fri, May 27, 2022 at 09:59:14AM -0700, Guenter Roeck wrote:
> Given that we (ChromeOS) have been hit by rng related
> issues before (specifically boot stalls on some hardware), I am quite
> concerned about the possible impact of this series for stable releases.
The urandom try_to_generate_entropy() change from 5.18 wasn't backported.
zx2c4@thinkpad ~/Projects/random-linux $ git diff linux-5.10.y:drivers/char/random.c master:drivers/char/random.c
[...snip...]
@@ -1292,6 +1311,13 @@ static ssize_t urandom_read_iter(struct kiocb *kiocb, struct iov_iter *iter)
{
static int maxwarn = 10;
+ /*
+ * Opportunistically attempt to initialize the RNG on platforms that
+ * have fast cycle counters, but don't (for now) require it to succeed.
+ */
+ if (!crng_ready())
+ try_to_generate_entropy();
+
if (!crng_ready()) {
if (!ratelimit_disable && maxwarn <= 0)
++urandom_warning.missed;
Jason
