From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 0/5 V5] Avoid soft lockup message when KVM is stopped by host Date: Thu, 15 Dec 2011 12:21:16 +0200 Message-ID: <4EE9CA1C.3010801@redhat.com> References: <1323116344-17911-1-git-send-email-emunson@mgebm.net> <4EDF7B0D.4060001@redhat.com> <20111214121622.GB18317@amt.cnet> <4EE8B53C.6070502@redhat.com> <20111214182101.GB21945@amt.cnet> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Eric B Munson , mingo@redhat.com, hpa@zytor.com, arnd@arndb.de, ryanh@linux.vnet.ibm.com, aliguori@us.ibm.com, jeremy.fitzhardinge@citrix.com, levinsasha928@gmail.com, Jan Kiszka , kvm@vger.kernel.org, linux-arch@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org To: Marcelo Tosatti Return-path: In-Reply-To: <20111214182101.GB21945@amt.cnet> Sender: linux-arch-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 12/14/2011 08:21 PM, Marcelo Tosatti wrote: > On Wed, Dec 14, 2011 at 04:39:56PM +0200, Avi Kivity wrote: > > On 12/14/2011 02:16 PM, Marcelo Tosatti wrote: > > > > Having this controlled from userspace means it doesn't work for SIGSTOP > > > > or for long scheduling delays. What about doing this automatically > > > > based on preempt notifiers? > > > > > > Long scheduling delays should be considered hangups from the guest > > > perspective. > > > > Why? To the guest it looks like slow hardware, but it will interpret it > > as a softlockup. > > Slow enough that progress of the watchdog thread is unable to keep up > with timer interrupt processing. This is considered a hang and > should be reported. It's not a guest hang though! -- error compiling committee.c: too many arguments to function