From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoffer Dall Subject: Re: [RESEND PATCH 0/2] arm/arm64: kvm: Disable branch profiling in HYP code Date: Sat, 21 Oct 2017 17:04:29 +0200 Message-ID: <20171021150429.GC12618@cbox> References: <1508499257-10014-1-git-send-email-julien.thierry@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id E86EC406D0 for ; Sat, 21 Oct 2017 11:03:22 -0400 (EDT) Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id JUgyyulCoWDU for ; Sat, 21 Oct 2017 11:03:22 -0400 (EDT) Received: from mail-wm0-f42.google.com (mail-wm0-f42.google.com [74.125.82.42]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 009E5406BB for ; Sat, 21 Oct 2017 11:03:21 -0400 (EDT) Received: by mail-wm0-f42.google.com with SMTP id 196so3599480wma.1 for ; Sat, 21 Oct 2017 08:04:31 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1508499257-10014-1-git-send-email-julien.thierry@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: Julien Thierry Cc: marc.zyngier@arm.com, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org List-Id: kvmarm@lists.cs.columbia.edu On Fri, Oct 20, 2017 at 12:34:15PM +0100, Julien Thierry wrote: > [Resending for Christoffer and adding kvmarm to recipients] > > Hi, > > When enabling branch profiling, a lockup occurs at boot time, after > displaying: "kvm [1]: Hyp mode initialized successfully" > > The issue is caused by the Hyp code getting instrumented and trying to > access unmapped code or data, which happens when trying to initialize EL2. > > So it also seems like KVM is misleadingly announcing it was initialized and > yet gets stuck during initialization. > > * First patch deals with printing the initialization message once KVM has > fully initialized Hyp mode > * Second patch actually disables branch profiling instrumentation in Hyp > code Applied, thanks. -Christoffer