From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id DCEC8FD45F8 for ; Wed, 25 Feb 2026 22:10:01 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vvN4h-0007vS-3E; Wed, 25 Feb 2026 17:09:43 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vvN4L-0007Dq-TE; Wed, 25 Feb 2026 17:09:22 -0500 Received: from pdx-out-013.esa.us-west-2.outbound.mail-perimeter.amazon.com ([34.218.115.239]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vvN4J-00011j-LM; Wed, 25 Feb 2026 17:09:21 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazoncorp2; t=1772057359; x=1803593359; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=uVNVDznm7NxQ+bwTqP9jZD0VXeg2067NIquqLqqPp8k=; b=U5mC9BK+iVMdimumMT2zakxt78h5+790ESM4wmRxiUrPm2T5+6ks5T1x k0C5yvo2NaFe0KjkGzeHNnitL1maf6HWxRJ55qCx+zYqs7tmlgZ2U5yYA d7dq/iqpcY7ZK5nIM360PIoBgWScNKUMbuEwb9lFGcyrlAt5+7zN6SUi9 kSjOyszmcYeaSF5KHytolo1F64G9b23IIAKptQOwWx/m6FEJWPY+PXA9k sp0MY5PVZO1BQ3SJJze5JGEej3eva9jdNRxlua+dO5k0XX9gxSA6fSipm AqkdGKEJnVslt0iVzMGCSBOS+L6hQny+BZYFJFTE3QUGyzj27sJmFnhqY g==; X-CSE-ConnectionGUID: IeaVlMmDS7WNUWMK1MkrWQ== X-CSE-MsgGUID: Z7efPULUSA+SjoWLVIEdmw== X-IronPort-AV: E=Sophos;i="6.21,311,1763424000"; d="scan'208";a="13613953" Received: from ip-10-5-9-48.us-west-2.compute.internal (HELO smtpout.naws.us-west-2.prod.farcaster.email.amazon.dev) ([10.5.9.48]) by internal-pdx-out-013.esa.us-west-2.outbound.mail-perimeter.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Feb 2026 22:09:15 +0000 Received: from EX19MTAUWB002.ant.amazon.com [205.251.233.48:17534] by smtpin.naws.us-west-2.prod.farcaster.email.amazon.dev [10.0.50.69:2525] with esmtp (Farcaster) id 5dba8a24-f6f6-41a1-9f16-3a76b3f38820; Wed, 25 Feb 2026 22:09:15 +0000 (UTC) X-Farcaster-Flow-ID: 5dba8a24-f6f6-41a1-9f16-3a76b3f38820 Received: from EX19D020UWC004.ant.amazon.com (10.13.138.149) by EX19MTAUWB002.ant.amazon.com (10.250.64.231) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.2562.37; Wed, 25 Feb 2026 22:09:13 +0000 Received: from ip-10-253-83-51.amazon.com (172.19.99.218) by EX19D020UWC004.ant.amazon.com (10.13.138.149) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.2562.37; Wed, 25 Feb 2026 22:09:10 +0000 From: Alexander Graf To: CC: , Peter Maydell , "Thomas Huth" , , , , , Cornelia Huck , , Dorjoy Chowdhury , Pierrick Bouvier , Paolo Bonzini , Tyler Fanelli , , Subject: [PATCH v3 07/11] target/arm/cpu64: Allow -host for nitro Date: Wed, 25 Feb 2026 22:08:01 +0000 Message-ID: <20260225220807.33092-8-graf@amazon.com> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20260225220807.33092-1-graf@amazon.com> References: <20260225220807.33092-1-graf@amazon.com> MIME-Version: 1.0 X-Originating-IP: [172.19.99.218] X-ClientProxiedBy: EX19D036UWB001.ant.amazon.com (10.13.139.133) To EX19D020UWC004.ant.amazon.com (10.13.138.149) Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=34.218.115.239; envelope-from=prvs=509822c20=graf@amazon.de; helo=pdx-out-013.esa.us-west-2.outbound.mail-perimeter.amazon.com X-Spam_score_int: -1 X-Spam_score: -0.2 X-Spam_bar: / X-Spam_report: (-0.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HEADER_FROM_DIFFERENT_DOMAINS=0.249, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.734, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.78, SPF_HELO_NONE=0.001, T_SPF_PERMERROR=0.01, UNPARSEABLE_RELAY=0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-arm@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-arm-bounces+qemu-arm=archiver.kernel.org@nongnu.org Sender: qemu-arm-bounces+qemu-arm=archiver.kernel.org@nongnu.org The nitro accel does not actually make use of CPU emulation or details: It always uses the host CPU regardless of configuration. Machines for the nitro accel select the host CPU type as default to have a clear statement of the above and to have a unified cpu type across all supported architectures. The arm64 logic on Linux currently only allows -cpu host for KVM based virtual machines. Add a special case for nitro so that when the nitro accel is active, it allows use of the host cpu type. Signed-off-by: Alexander Graf --- target/arm/cpu64.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c index 5d7c6b7fbb..c01051f038 100644 --- a/target/arm/cpu64.c +++ b/target/arm/cpu64.c @@ -765,6 +765,14 @@ static void aarch64_a53_initfn(Object *obj) static void aarch64_host_initfn(Object *obj) { ARMCPU *cpu = ARM_CPU(obj); + +#if defined(CONFIG_NITRO) + if (nitro_enabled()) { + /* The nitro accel uses -cpu host, but does not actually consume it */ + return; + } +#endif + #if defined(CONFIG_KVM) kvm_arm_set_cpu_features_from_host(cpu); if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) { -- 2.47.1 Amazon Web Services Development Center Germany GmbH Tamara-Danz-Str. 13 10243 Berlin Geschaeftsfuehrung: Christof Hellmis, Andreas Stieger Eingetragen am Amtsgericht Charlottenburg unter HRB 257764 B Sitz: Berlin Ust-ID: DE 365 538 597