From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3xCSGH0SSgzDrCn for ; Thu, 20 Jul 2017 05:46:46 +1000 (AEST) Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v6JJhonH002155 for ; Wed, 19 Jul 2017 15:46:44 -0400 Received: from e24smtp04.br.ibm.com (e24smtp04.br.ibm.com [32.104.18.25]) by mx0b-001b2d01.pphosted.com with ESMTP id 2btdkw8k1a-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Wed, 19 Jul 2017 15:46:44 -0400 Received: from localhost by e24smtp04.br.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 19 Jul 2017 16:46:42 -0300 Received: from d24av02.br.ibm.com (d24av02.br.ibm.com [9.8.31.93]) by d24relay02.br.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v6JJkeFt18415664 for ; Wed, 19 Jul 2017 16:46:40 -0300 Received: from d24av02.br.ibm.com (localhost [127.0.0.1]) by d24av02.br.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id v6JJkgmp025837 for ; Wed, 19 Jul 2017 16:46:42 -0300 Date: Wed, 19 Jul 2017 16:46:34 -0300 From: joserz@linux.vnet.ibm.com To: linuxppc-dev@lists.ozlabs.org Cc: benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, oohall@gmail.com Subject: KVM guests freeze under upstream kernel MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Message-Id: <20170719194634.GA1222@pacoca> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hello! We're not able to boot any KVM guest using upstream kernel (cb8c65ccff7f77d0285f1b126c72d37b2572c865 - 4.13.0-rc1+). After reaching the SLOF initial counting, the guest simply freezes: SLOF ********************************************************************** QEMU Starting Build Date = Mar 3 2017 13:29:19 FW Version = git-66d250ef0fd06bb8 Press "s" to enter Open Firmware. C0360 After bisecting I found the commit: https://github.com/torvalds/linux/commit/ebd3119 powerpc/mm: Add devmap support for ppc64 Add support for the devmap bit on PTEs and PMDs for PPC64 Book3S. This is used to differentiate device backed memory from transparent huge pages since they are handled in more or less the same manner by the core mm code. Reverting the commit and rebuilding 4.13.0-rc1+ was enough to make a workaround. But I'll need some help from you guys in order to solve it. Thanks! Jose Ziviani