On Wed, May 22, 2024 at 03:53:23PM -0700, Linus Torvalds wrote: > > That said, looking at the code in question, there are other oddities > going on. Even the "we found a favorite new rng" case looks rather > strange. The thread we use - nice and asynchronous - seems to sleep > only if the randomness source is emptied. > > What if you have a really good source of hw randomness? That looks > like a busy loop to me, but hopefully I'm missing something obvious. Yes that does look strange. So I dug up the original patch at https://lore.kernel.org/all/20140317165012.GC1763@xxxxxx/ and therein lies the answer. It's relying on random.c to push back when the amount of new entropy exceeds what it needs. IOW we will sleep via add_hwgenerator_randomness when random.c decides that enough is enough. In fact the rate is much less now compared to when the patch was first applied. Cheers, -- Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
