lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 1 Nov 2017 21:42:42 +0100 From: Borislav Petkov <bp@...en8.de> To: Dave Hansen <dave.hansen@...ux.intel.com> Cc: linux-kernel@...r.kernel.org, linux-mm@...ck.org, moritz.lipp@...k.tugraz.at, daniel.gruss@...k.tugraz.at, michael.schwarz@...k.tugraz.at, luto@...nel.org, torvalds@...ux-foundation.org, keescook@...gle.com, hughd@...gle.com, x86@...nel.org Subject: Re: [PATCH 01/23] x86, kaiser: prepare assembly for entry/exit CR3 switching On Wed, Nov 01, 2017 at 11:27:48AM -0700, Dave Hansen wrote: > This allows for a tiny optimization of Andy's that I realize I must have > blown away at some point. It lets us do a 32-bit-register instruction > (and using %eXX) when checking KAISER_SWITCH_MASK instead of a 64-bit > register via %rXX. > > I don't feel strongly about maintaining that optimization it looks weird > and surely doesn't actually do much. Yeah, and consistent syntax would probably bring more. > Thanks for catching that. We can kill one of these. I'm inclined to > kill the first one. Looking at the second one since we've just saved > off ptregs, that should make %rdi safe to clobber without the push/pop > at all. > > Does that seem like it would work? Yap, sounds about right. Thx. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.
Powered by blists - more mailing lists