Re: intel_rng: FWH not detected (and no entropy)

From: Pierre Chifflier
Date: Thu Aug 23 2007 - 10:41:24 EST


On Thu, Aug 23, 2007 at 09:53:04AM -0300, Henrique de Moraes Holschuh wrote:
> On Thu, 23 Aug 2007, Pierre Chifflier wrote:
> > I'm not sure the mhat a hardware RNG is present, so I want to check.
>
> Open the mobo, and locate all FLASH chips. If one of them is a 82802AB or
> 82802AC, then you *MIGHT* have an Intel FWH with a HRNG (some of the FWHs
> have their RNGs disabled, and since Intel stopped guaranteeing the RNG is
> there, they would install one such FWH in their boards just the same). If
> none are a 82802AB or 82802AC, you don't have an Intel FWH with a HRNG.
>
> Even if you had an Intel board that is known to sometimes have an Intel FWH
> with an RNG, like the D875PBZ, that wouldn't mean much. They could have
> used an non-Intel equivalent part for that production run, for unknown
> reasons. You really have to check.

Well, I've seen nothing more than the 82801DB (which was listed in
lspci). So maybe there is no HRNG :(

This leaves the main problem, which is the lack of entropy. Does anyone
have an idea on how to solve this problem ?
It appeared with recent kernels. For ex, 2.6.8 had an entropy pool
always > 3000, while 2.6.18 and other recent kernels show ~ 150.

# sysctl kernel.random.poolsize
kernel.random.poolsize = 4096
# sysctl kernel.random.entropy_avail
kernel.random.entropy_avail = 196

This is really annoying, since the box should also use SSL/TLS
operations, and it will be real slow ..

Regards,
Pierre
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