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: Fri, 18 Aug 2017 14:35:09 +0200 From: Paolo Bonzini <pbonzini@...hat.com> To: David Hildenbrand <david@...hat.com>, linux-kernel@...r.kernel.org, kvm@...r.kernel.org Cc: rkrcmar@...hat.com, "Michael S. Tsirkin" <mst@...hat.com>, stable@...r.kernel.org Subject: Re: [PATCH] kvm: VMX: do not use vm-exit instruction length for fast MMIO On 18/08/2017 13:57, David Hildenbrand wrote: > What about a hack: > > 1. clear instruction length when entering > 2. check if instruction length is set when trying to forward the RIP > 2a. if set, use it > 2b. if not set, compute it It's undefined, so we don't know that the instruction length remains zero (also, on older processors and possibly some nested setups the field is read-only). Testing the hypervisor bit is the first line of action. Paolo > this at least should give full speedup in existing setups. Not 99% > architecturally correct but might just work. >
Powered by blists - more mailing lists