From mboxrd@z Thu Jan 1 00:00:00 1970 From: Aravind Gopalakrishnan Subject: Re: [PATCH 4/6] x86/emulate: Support for emulating software event injection Date: Fri, 26 Sep 2014 16:09:27 -0500 Message-ID: <5425D607.4030901@amd.com> References: <1411484611-31027-1-git-send-email-andrew.cooper3@citrix.com> <1411484611-31027-5-git-send-email-andrew.cooper3@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1411484611-31027-5-git-send-email-andrew.cooper3@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Andrew Cooper , Xen-devel Cc: Boris Ostrovsky , Suravee Suthikulpanit , Jan Beulich List-Id: xen-devel@lists.xenproject.org On 9/23/2014 10:03 AM, Andrew Cooper wrote: > AMD SVM requires all software events to have their injection emulated if > hardware lacks NextRIP support. In addition, `icebp` (opcode 0xf1) injection > requires emulation in all cases, even with hardware NextRIP support. > > Emulating full control transfers is overkill for our needs. All that matters > is that guest userspace can't bypass the descriptor DPL check. Any guest OS > which would incur other faults as part of injection is going to end up with a > double fault instead, and won't be in a position to care that the faulting eip > is wrong. > > Reported-by: Andrei LUTAS > Signed-off-by: Andrew Cooper > Signed-off-by: Jan Beulich > CC: Boris Ostrovsky > CC: Suravee Suthikulpanit > CC: Aravind Gopalakrishnan > Reviewed-by: Aravind Gopalakrishnan