From patchwork Fri Oct 9 10:19:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gibson X-Patchwork-Id: 271759 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1C632C433E7 for ; Fri, 9 Oct 2020 10:22:45 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8E0262226B for ; Fri, 9 Oct 2020 10:22:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.b="OsfWPTv7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8E0262226B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=gibson.dropbear.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:48686 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kQpXv-0007kj-Bk for qemu-devel@archiver.kernel.org; Fri, 09 Oct 2020 06:22:43 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42934) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kQpVM-00059c-BR for qemu-devel@nongnu.org; Fri, 09 Oct 2020 06:20:04 -0400 Received: from ozlabs.org ([203.11.71.1]:40495) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kQpVK-0001lq-61 for qemu-devel@nongnu.org; Fri, 09 Oct 2020 06:20:04 -0400 Received: by ozlabs.org (Postfix, from userid 1007) id 4C73wW1hLSz9sTR; Fri, 9 Oct 2020 21:19:55 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gibson.dropbear.id.au; s=201602; t=1602238795; bh=ReJY2aou6sp3rSgeP/ZOyb10zb5wURuuxehViZoJX7E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OsfWPTv7eYSVXeRyepAGA1autXz8l3nlvCTENQiaO7nCbW+5vTjUeq3SuAdtFb2Cp BqMW/+yjpDCG1bRHai6zy/B0P8MOJcZlFwOhVlgEhgwlzmE9tg7/3IfZn8MHMiky2e uG23r91MYeiAZXfQ8xgZtlNPTtucNkFNtttTqdzo= From: David Gibson To: peter.maydell@linaro.org Subject: [PULL 01/20] spapr: Handle HPT allocation failure in nested guest Date: Fri, 9 Oct 2020 21:19:32 +1100 Message-Id: <20201009101951.1569252-2-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201009101951.1569252-1-david@gibson.dropbear.id.au> References: <20201009101951.1569252-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Received-SPF: pass client-ip=203.11.71.1; envelope-from=dgibson@ozlabs.org; helo=ozlabs.org X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/09 06:19:55 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] X-Spam_score_int: -17 X-Spam_score: -1.8 X-Spam_bar: - X-Spam_report: (-1.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HEADER_FROM_DIFFERENT_DOMAINS=0.25, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: dbarboza@redhat.com, Fabiano Rosas , qemu-devel@nongnu.org, groug@kaod.org, Satheesh Rajendran , qemu-ppc@nonngu.org, David Gibson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Fabiano Rosas The nested KVM code does not yet support HPT guests. Calling the KVM_CAP_PPC_ALLOC_HTAB ioctl currently leads to KVM setting the guest as HPT and erroneously executing code in L1 that should only run in hypervisor mode, leading to an exception in the L1 vcpu thread when it enters the nested guest. This can be reproduced with -machine max-cpu-compat=power8 in the L2 guest command line. The KVM code has since been modified to fail the ioctl when running in a nested environment so QEMU needs to be able to handle that. This patch provides an error message informing the user about the lack of support for HPT in nested guests. Reported-by: Satheesh Rajendran Signed-off-by: Fabiano Rosas Message-Id: <20200911043123.204162-1-farosas@linux.ibm.com> Reviewed-by: Greg Kurz Signed-off-by: David Gibson --- hw/ppc/spapr.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index 2db810f73a..544a1947d9 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -1483,6 +1483,12 @@ void spapr_reallocate_hpt(SpaprMachineState *spapr, int shift, spapr_free_hpt(spapr); rc = kvmppc_reset_htab(shift); + + if (rc == -EOPNOTSUPP) { + error_setg(errp, "HPT not supported in nested guests"); + return; + } + if (rc < 0) { /* kernel-side HPT needed, but couldn't allocate one */ error_setg_errno(errp, errno,