From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50175) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZykIV-0006rs-WF for qemu-devel@nongnu.org; Tue, 17 Nov 2015 12:44:04 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZykIQ-0006hP-RF for qemu-devel@nongnu.org; Tue, 17 Nov 2015 12:44:03 -0500 Received: from mail-wm0-x22b.google.com ([2a00:1450:400c:c09::22b]:33378) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZykIQ-0006hL-L7 for qemu-devel@nongnu.org; Tue, 17 Nov 2015 12:43:58 -0500 Received: by wmec201 with SMTP id c201so240201803wme.0 for ; Tue, 17 Nov 2015 09:43:58 -0800 (PST) Sender: Paolo Bonzini References: <1436429849-18052-1-git-send-email-rth@twiddle.net> From: Paolo Bonzini Message-ID: <564B675B.30207@redhat.com> Date: Tue, 17 Nov 2015 18:43:55 +0100 MIME-Version: 1.0 In-Reply-To: <1436429849-18052-1-git-send-email-rth@twiddle.net> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PATCH 00/14] target-i386: Implement MPX extension List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Richard Henderson , qemu-devel@nongnu.org Cc: ehabkost@redhat.com On 09/07/2015 10:17, Richard Henderson wrote: > I'm still in the process of testing this, as there's no code > written for it yet and hardware to compare against doesn't > start shipping until (probably) August. > > But in the meantime there are a number of holes that I found > in XSAVE support that might affect KVM, and one question wrt > SMM support that affects MPX. So I thought I'd get some > feedback on this sooner than later. > > This patch set depends on the addressing cleanup patchset that > I just posted. It ought to depend on Pavel Dovgalyuk's exception > handling cleanup patchset, but I haven't included that in my tree. > > Comments? Hi Richard, it would be nice to have these patches---or at least the XSAVE support---in 2.6. I also have a PKRU implementation for TCG, but currently I'm only implementing RDPKRU/WRPKRU because I would like to build the XSAVE support on top of your patches. Regarding SMM support, there are three ways to go: 1) pester Intel some more so that they disclose the format of the SMM state save area; 2) just place BNDCFGS at a random offset that is left as reserved in AMD's manual; 3) do not save BNDCFGS at all since no one uses it anyway. *shrug* The holes in the computation of KVM's hflags are probably harmless, but nice to have anyway. Thanks for fixing them. Are there others that I missed? Paolo