From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCH v4] KVM: X86: Allow userspace to define the microcode version Date: Tue, 27 Feb 2018 10:43:03 +0100 Message-ID: <20180227094303.GA30022@pd.tnic> References: <1519698910-4272-1-git-send-email-wanpengli@tencent.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Cc: Paolo Bonzini , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Radim =?utf-8?B?S3LEjW3DocWZ?= , Liran Alon , Nadav Amit To: Wanpeng Li Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On Tue, Feb 27, 2018 at 09:38:12AM +0100, Paolo Bonzini wrote: > On 27/02/2018 03:35, Wanpeng Li wrote: > > From: Wanpeng Li > > > > Linux (among the others) has checks to make sure that certain features > > aren't enabled on a certain family/model/stepping if the microcode version > > isn't greater than or equal to a known good version. > > > > By exposing the real microcode version, we're preventing buggy guests that > > don't check that they are running virtualized (i.e., they should trust the > > hypervisor) from disabling features that are effectively not buggy. > > > > Suggested-by: Filippo Sironi > > Cc: Paolo Bonzini > > Cc: Radim Krčmář > > Cc: Liran Alon > > Cc: Nadav Amit > > Signed-off-by: Wanpeng Li > > --- > > v3 -> v4: > > * add the shifts back > > Please wait for a review instead of pushing new versions continuously. ... and pls CC me on your submissions. Thx. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.