On Tue, Jun 09, 2009 at 10:35:33AM -0400, Chuck Ebbert wrote: > The VIA Nano has a bug that makes the padlock unit fetch extra data > during encryption operations. Add workarounds for that, and enable > the driver on x86_64. Thanks! Where did you get the errata from, and what kind of document / revision is it? I have not seen that document so far. I've asked Centaur to confirm the errata, also inquired whether there will be a microcode update or a new stepping to fix it. If yes, we should add proper checks to the workaround to make sure it's only enabled when we need it. Out of curiosity: Only the ACE (crypto) is affected, not PHE (hashing)? I'll also put on my todo list to do some actual benchmarking to determine how much impact this bug has. I expect especially for storage encryption, many crypto operations will be page aligned and thus need the extra memcpy :( p.s.: the patch to enable padlock on x86_64 is already in the crypto-dev tree, as far as I know. Interestingly, I have not observed this problem so far, despite running dm-crypt on a nano for quite some time. Cheers, -- - Harald Welte <HaraldWelte@xxxxxxxxxxx> http://linux.via.com.tw/ ============================================================================ VIA Free and Open Source Software Liaison -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
