From nobody Mon Feb 9 15:10:18 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zoho.com; dkim=fail spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1495003062228707.9809034540608; Tue, 16 May 2017 23:37:42 -0700 (PDT) Received: from localhost ([::1]:45706 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dAsaZ-0006d1-Pd for importer@patchew.org; Wed, 17 May 2017 02:37:39 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59434) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dAsYz-0005PY-Vu for qemu-devel@nongnu.org; Wed, 17 May 2017 02:36:03 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dAsYw-0005Ai-3c for qemu-devel@nongnu.org; Wed, 17 May 2017 02:36:02 -0400 Received: from ozlabs.org ([103.22.144.67]:54933) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dAsYv-000595-Jl; Wed, 17 May 2017 02:35:58 -0400 Received: by ozlabs.org (Postfix, from userid 1007) id 3wSPhk6bhQz9s82; Wed, 17 May 2017 16:35:50 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gibson.dropbear.id.au; s=201602; t=1495002950; bh=wcz9HxbQa3YudH7bmFtWyATHOGC6fAOLBXKiBHScdEA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=f8ROGiZSe4GKLiAYfpa/JcXeEV93jJSYYq/oRy7dh9ktOZKNxv2lFbMBFYSdYf2CF /SIlGq6/LS2xQCumpTDEzj0gy7YJ9HHuFKIyjOGMTZ4ztGsHOpWZUBEZ2yXISbXpFr f65rnPuyhaRjEnZ1dahK3JEqzGmtLLKBXN/ngI+o= From: David Gibson To: abologna@redhat.com, thuth@redhat.com, lvivier@redhat.com Date: Wed, 17 May 2017 16:35:46 +1000 Message-Id: <20170517063547.23876-2-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.9.4 In-Reply-To: <20170517063547.23876-1-david@gibson.dropbear.id.au> References: <20170517063547.23876-1-david@gibson.dropbear.id.au> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 103.22.144.67 Subject: [Qemu-devel] [RFC 1/2] pseries: Split CAS PVR negotiation out into a separate function X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: aik@ozlabs.ru, qemu-devel@nongnu.org, mdroth@linux.vnet.ibm.com, qemu-ppc@nongnu.org, bharata@linux.vnet.ibm.com, David Gibson Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZohoMail: RDKM_2 RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Guests of the qemu machine type go through a feature negotiation process known as "client architecture support" (CAS) during early boot. This does a number of things, one of which is finding a CPU compatibility mode which can be supported by both guest and host. In fact the CPU negotiation is probably the single most complex part of the CAS process, so this splits it out into a helper function. We've recently made some mistakes in maintaining backward compatibility for old machine types here. Splitting this out will also make it easier to fix this. This also adds a possibly useful error message if the negotiation fails (i.e. if there is CPU mode that's suitable for both guest and host). Signed-off-by: David Gibson --- hw/ppc/spapr_hcall.c | 43 +++++++++++++++++++++++++++---------------- 1 file changed, 27 insertions(+), 16 deletions(-) diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c index 0d608d6..007ae8d 100644 --- a/hw/ppc/spapr_hcall.c +++ b/hw/ppc/spapr_hcall.c @@ -1047,19 +1047,13 @@ static target_ulong h_signal_sys_reset(PowerPCCPU *= cpu, } } =20 -static target_ulong h_client_architecture_support(PowerPCCPU *cpu, - sPAPRMachineState *spapr, - target_ulong opcode, - target_ulong *args) +static uint32_t cas_check_pvr(PowerPCCPU *cpu, target_ulong list, + Error **errp) { - target_ulong list =3D ppc64_phys_to_real(args[0]); - target_ulong ov_table; bool explicit_match =3D false; /* Matched the CPU's real PVR */ uint32_t max_compat =3D cpu->max_compat; uint32_t best_compat =3D 0; int i; - sPAPROptionVector *ov1_guest, *ov5_guest, *ov5_cas_old, *ov5_updates; - bool guest_radix; =20 /* * We scan the supplied table of PVRs looking for two things @@ -1090,26 +1084,43 @@ static target_ulong h_client_architecture_support(P= owerPCCPU *cpu, /* We couldn't find a suitable compatibility mode, and either * the guest doesn't support "raw" mode for this CPU, or raw * mode is disabled because a maximum compat mode is set */ - return H_HARDWARE; + error_setg(errp, "Couldn't negotiate a suitable PVR during CAS"); + return 0; } =20 /* Parsing finished */ trace_spapr_cas_pvr(cpu->compat_pvr, explicit_match, best_compat); =20 - /* Update CPUs */ - if (cpu->compat_pvr !=3D best_compat) { - Error *local_err =3D NULL; + return best_compat; +} + +static target_ulong h_client_architecture_support(PowerPCCPU *cpu, + sPAPRMachineState *spapr, + target_ulong opcode, + target_ulong *args) +{ + /* @ov_table points to the first option vector */ + target_ulong ov_table =3D ppc64_phys_to_real(args[0]); + uint32_t cas_pvr; + sPAPROptionVector *ov1_guest, *ov5_guest, *ov5_cas_old, *ov5_updates; + bool guest_radix; + Error *local_err =3D NULL; =20 - ppc_set_compat_all(best_compat, &local_err); + cas_pvr =3D cas_check_pvr(cpu, ov_table, &local_err); + if (local_err) { + error_report_err(local_err); + return H_HARDWARE; + } + + /* Update CPUs */ + if (cpu->compat_pvr !=3D cas_pvr) { + ppc_set_compat_all(cas_pvr, &local_err); if (local_err) { error_report_err(local_err); return H_HARDWARE; } } =20 - /* For the future use: here @ov_table points to the first option vecto= r */ - ov_table =3D list; - ov1_guest =3D spapr_ovec_parse_vector(ov_table, 1); ov5_guest =3D spapr_ovec_parse_vector(ov_table, 5); if (spapr_ovec_test(ov5_guest, OV5_MMU_BOTH)) { --=20 2.9.4