Messages in this thread Patch in this message | | | Date | Thu, 21 May 2015 16:19:54 +0800 | From | Herbert Xu <> | Subject | random: Wake up all getrandom(2) callers when pool is ready |
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On Thu, May 21, 2015 at 09:55:17AM +0200, Stephan Mueller wrote: > > So, I will create a 2nd wait queue in random.c for uninterruptible waits, > change the get_blocking_random_bytes back to void and use wait_event to wait > for the initialization.
Hold your horses. You don't need a second queue, you just need to change wake_up_interruptible to wake_up.
Hmm, in fact shouldn't this be wake_up_all? Otherwise what are the other getrandom(2) callers going to do? Ted?
---8<--- If more than one application invokes getrandom(2) before the pool is ready, then all bar one will be stuck forever because we use wake_up_interruptible which wakes up a single task.
This patch replaces it with wake_up_all.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/drivers/char/random.c b/drivers/char/random.c index 9cd6968..8b8c46b 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -660,7 +660,7 @@ retry: r->entropy_total = 0; if (r == &nonblocking_pool) { prandom_reseed_late(); - wake_up_interruptible(&urandom_init_wait); + wake_up_all(&urandom_init_wait); pr_notice("random: %s pool is initialized\n", r->name); } } Cheers, -- Email: Herbert Xu <herbert@gondor.apana.org.au> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
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