Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761241Ab2BNVRZ (ORCPT ); Tue, 14 Feb 2012 16:17:25 -0500 Received: from oz.csail.mit.edu ([128.30.30.239]:37354 "EHLO mail.mgebm.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761223Ab2BNVRW (ORCPT ); Tue, 14 Feb 2012 16:17:22 -0500 Date: Tue, 14 Feb 2012 16:17:20 -0500 From: Eric B Munson To: Marcelo Tosatti Cc: avi@redhat.com, mingo@redhat.com, hpa@zytor.com, ryanh@linux.vnet.ibm.com, aliguori@us.ibm.com, kvm@vger.kernel.org, linux-arch@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/4 V13] Avoid soft lockup message when KVM is stopped by host Message-ID: <20120214211720.GC6881@mgebm.net> References: <1328713666-11424-1-git-send-email-emunson@mgebm.net> <20120214152931.GA6881@mgebm.net> <20120214153836.GA21106@amt.cnet> <20120214155013.GB6881@mgebm.net> <20120214161009.GA21515@amt.cnet> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="jousvV0MzM2p6OtC" Content-Disposition: inline In-Reply-To: <20120214161009.GA21515@amt.cnet> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3559 Lines: 101 --jousvV0MzM2p6OtC Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, 14 Feb 2012, Marcelo Tosatti wrote: > On Tue, Feb 14, 2012 at 10:50:13AM -0500, Eric B Munson wrote: > > On Tue, 14 Feb 2012, Marcelo Tosatti wrote: > >=20 > > > On Tue, Feb 14, 2012 at 10:29:31AM -0500, Eric B Munson wrote: > > > > On Wed, 08 Feb 2012, Eric B Munson wrote: > > > >=20 > > > > >=20 > > > > > When a guest kernel is stopped by the host hypervisor it can look= like a soft > > > > > lockup to the guest kernel. This false warning can mask later so= ft lockup > > > > > warnings which may be real. This patch series adds a method for = a host > > > > > hypervisor to communicate to a guest kernel that it is being stop= ped. The > > > > > final patch in the series has the watchdog check this flag when i= t goes to > > > > > issue a soft lockup warning and skip the warning if the guest kno= ws it was > > > > > stopped. > > > > >=20 > > > > > It was attempted to solve this in Qemu, but the side effects of s= aving and > > > > > restoring the clock and tsc for each vcpu put the wall clock of t= he guest behind > > > > > by the amount of time of the pause. This forces a guest to have = ntp running > > > > > in order to keep the wall clock accurate. > > > >=20 > > > > Avi, > > > >=20 > > > > Is this set fit for merging or is there something else you want cha= nged? > > >=20 > > > Eric, > > >=20 > > > On Message-ID: <20120210160536.GA23363@amt.cnet>, i asked: > > >=20 > > > How is the stub getting included for other architectures again? > > >=20 > >=20 > > Marcelo, > >=20 > > Sorry, I put out V13 to answer that. There is a stub in asm-generic th= at was > > lost in the V11-V12 rebase. This stub has be included in the V13 set. > >=20 > > Eric >=20 > Eric,=20 >=20 > I know the stub has been included in the series. But i am asking how=20 > it is #include'ed for other architectures? (can't see that). Marcelo, kernel/watchdog.c now includes linux/kvm_para.h which includes asm/kvm_para= =2Eh. The check_and_clear function is defined in arch include/asm/kvm_para.h or in asm-generic/kvm_para.h for any arch lacking the specific header in their asm include dir. If I have misunderstood how these headers work, please let me know and I will fix it. Eric --jousvV0MzM2p6OtC Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAEBAgAGBQJPOs9gAAoJEKhG9nGc1bpJN50P/3o6c0GrXC2Xn653CeG74J6i BZc6rsJgVQVQWiFdlb0pMWy8l1m18QgJGY2zYxB04Sr5U/Hv7Gb3g+08fVYqJkAM RGlFGjZSLNPfQ4huyGnkWyY92hMf1x6YcmqWwcXR30mpkugJ3ARDL00DGyR06WE9 9BzijOQr3Xn3wUMtMY3sDzj4KwnZduBYVh2zCxaGouUs5gtlMsDAgKt69Ye6gMtR CY6wDwFm3cS/XsPBekxqr7ZumrMVD5hV5NkmlpT4xexHtca2PfWoojfEVSHnDR7W yqjszhtS4rcMyr7u9i+j3StI6joB3EjOkYrHFMKPP4/3kL9tfymXk3EedTdulTu0 730Dxxxes6DILE1ZjZfdp1NpVgayGIx3Uu6yB6EnHQ+mcnQCjfAFKOs31K5B7eHq ioIxTBOKOs3/blHSEK4li05oGR7iGa7yOHrx35sh/YevZtOYW1kapJJ1DrCGUnIu xwBlQmPwppAU6xVl5AqruWyJnCDXhSk13+ZO/A4OZjb/uHBkeBG7R1KrbSrTYv1m VlfffMhbqEKrsAqMxI5RQBZyqC+jRr8pCZI3IONi/ULFGtZwnA4PyEyfSthSi+wW 8d/Jjnfr6Rc2Buu654E59D7SsYo3XYntwSMx/0RF/U7tIbwoxt6k15oZM9sl0Phb IQsVK0/fsmptlR+oE6FK =XueJ -----END PGP SIGNATURE----- --jousvV0MzM2p6OtC-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/