{"id":2230486,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2230486/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260429190532.26538-9-mohamed@unpredictable.fr/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.1/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20260429190532.26538-9-mohamed@unpredictable.fr>","date":"2026-04-29T19:05:25","name":"[v21,08/15] hvf: arm: allow exposing minimal PMU for kernel-irqchip=on","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"10538611a4e2b4f8e564e15cd57ebd4decaeb2c5","submitter":{"id":91318,"url":"http://patchwork.ozlabs.org/api/1.1/people/91318/?format=json","name":"Mohamed Mediouni","email":"mohamed@unpredictable.fr"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260429190532.26538-9-mohamed@unpredictable.fr/mbox/","series":[{"id":502138,"url":"http://patchwork.ozlabs.org/api/1.1/series/502138/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=502138","date":"2026-04-29T19:05:29","name":"HVF: Add support for platform vGIC and nested virtualisation","version":21,"mbox":"http://patchwork.ozlabs.org/series/502138/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2230486/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2230486/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=unpredictable.fr header.i=@unpredictable.fr\n header.a=rsa-sha256 header.s=sig1 header.b=GHvgYPUZ;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; helo=lists1p.gnu.org;\n envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n receiver=patchwork.ozlabs.org)"],"Received":["from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17])\n\t(using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4g5RdT3FZhz1xqf\n\tfor ; Thu, 30 Apr 2026 05:07:41 +1000 (AEST)","from localhost ([::1] helo=lists1p.gnu.org)\n\tby lists1p.gnu.org with esmtp (Exim 4.90_1)\n\t(envelope-from )\n\tid 1wIAEb-0001oA-2a; Wed, 29 Apr 2026 15:06:09 -0400","from eggs.gnu.org ([2001:470:142:3::10])\n by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256)\n (Exim 4.90_1) (envelope-from )\n id 1wIAEZ-0001n9-EL\n for qemu-devel@nongnu.org; Wed, 29 Apr 2026 15:06:07 -0400","from p-west3-cluster3-host8-snip4-5.eps.apple.com ([57.103.72.206]\n helo=outbound.ms.icloud.com)\n by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256)\n (Exim 4.90_1) (envelope-from )\n id 1wIAEW-0000Nk-JH\n for qemu-devel@nongnu.org; Wed, 29 Apr 2026 15:06:07 -0400","from outbound.ms.icloud.com (unknown [127.0.0.2])\n by p00-icloudmta-asmtp-us-west-3a-60-percent-6 (Postfix) with ESMTPS id\n 501DA18002E8; Wed, 29 Apr 2026 19:06:01 +0000 (UTC)","from localhost.localdomain (unknown [17.57.154.37])\n by p00-icloudmta-asmtp-us-west-3a-60-percent-6 (Postfix) with ESMTPSA id\n 78D5618005CA; Wed, 29 Apr 2026 19:05:58 +0000 (UTC)"],"X-ICL-Out-Info":"\n HUtFAUMHWwJACUgBTUQeDx5WFlZNRAJCTQFIHV8DWRxBAUkdXw9LVxQEFVwFVgZXFHkNXR1FDlYZWgxSD1sOHBZLWFUJCgZdGFgVVgl3HlwASx1XBFQfUxJVHR0LRUtAEwRJAE1fDl4fBBdGGVUERx5dVl4eGQJRHFYNV0NUBF9QSQxBUGxaAEcXSB1dGVlvUF0cDhhZG0AVXRFQGVYJXhUXHkFNWgJWTQVKA18BWwZCAEkKXQJYAF4LTgZeD0YLXVQXWwxaDlYwTBZDH1IPWxNNGVEBUkVUAgdYRxRHDg8TTAtHAlo0Vh9UGVoD","Dkim-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=unpredictable.fr;\n s=sig1; t=1777489563; x=1780081563;\n bh=1/v/2pEP4nLxYkH1Z43qTSg56sckGJLMILFhZ9ygbpU=;\n h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type:x-icloud-hme;\n b=GHvgYPUZ7tZ2cjCzZnPiDgPFeO88hhi7vFOhs0xZZsAZwLZcPA0nWPAggRAOOSwFOxQLxduaMWt1gDyCboShKLTOi3kEytOq9jdxR67mk10WUL9B6rXEzNho4mroC4imHW6WNlKLZ0W8wrFkecm0g9McHHVjcVBmd6ul4hI0ocKPRZXNUtF51vJqcEetvJb45PukqF17Fj7xFP+tXsdRWCQof7cfPmJJL9/O/NhckjCAKxl1c6awAkUff+SS0/KNCKL0HdMwDibHntQsWeUZ1XiMZp9Q/Ss8PQjK48FFDBlFyb12VMnNVli2HdSFqvmz/DRuevsYtotwFkuYOwIIgA==","mail-alias-created-date":"1752046281608","From":"Mohamed Mediouni ","To":"qemu-devel@nongnu.org","Cc":"Phil Dennis-Jordan ,\n Yanan Wang , Paolo Bonzini ,\n Roman Bolshakov ,\n =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= ,\n qemu-arm@nongnu.org, Zhao Liu ,\n Alexander Graf , Eduardo Habkost ,\n Marcel Apfelbaum ,\n Peter Maydell ,\n Mohamed Mediouni ","Subject":"[PATCH v21 08/15] hvf: arm: allow exposing minimal PMU for\n kernel-irqchip=on","Date":"Wed, 29 Apr 2026 21:05:25 +0200","Message-ID":"<20260429190532.26538-9-mohamed@unpredictable.fr>","X-Mailer":"git-send-email 2.50.1","In-Reply-To":"<20260429190532.26538-1-mohamed@unpredictable.fr>","References":"<20260429190532.26538-1-mohamed@unpredictable.fr>","MIME-Version":"1.0","Content-Type":"text/plain; charset=UTF-8","Content-Transfer-Encoding":"8bit","X-Authority-Info-Out":"v=2.4 cv=TPRIilla c=1 sm=1 tr=0 ts=69f2569a\n cx=c_apl:c_pps:t_out a=qkKslKyYc0ctBTeLUVfTFg==:117 a=IkcTkHD0fZMA:10\n a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22 a=KKAkSRfTAAAA:8\n a=DcFNSUfH6uGOuzfjeGAA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10\n a=cvBusfyB2V15izCimMoJ:22","X-Proofpoint-GUID":"82PdqqcEDhyBpJcOvbi3Qll_ac4Mly3A","X-Proofpoint-Spam-Details-Enc":"AW1haW4tMjYwNDI5MDE5MCBTYWx0ZWRfX0m+bBDluozrR\n poHjYG0mMq50hMlw4rAqdln5JKNrkOu/eB0nuZ3nNeUmMkmpApmsCWX3DoQ134dsRAZQtVW5Gsk\n 134U7/1xwJbUquOPdbsx4IvFfZCxomGNfdFdLAQ5gYCvsNLxs/QY3SMkrI4lTgZUetwzuosXIqj\n E0SYWhLL3i0B+uWoAhk+HnmO4II0U3TZOMhLbDclBWkckaSFLvhcaJiBDV5PeMa65gGW8KHjKZp\n WvUPE7sbfo0cIAHdRyuYcvlekLeRiFz6Svp4Qy93PxGQZeEGLa72NV7mkN5QAPv7b48AKVrFOsm\n rWe1xycw5L+UgzUx0nTWEBTwv+JcL/XrzxBZqliwgUKKCu5CFYtlqIxX+4iW9I=","X-Proofpoint-ORIG-GUID":"82PdqqcEDhyBpJcOvbi3Qll_ac4Mly3A","Received-SPF":"pass client-ip=57.103.72.206;\n envelope-from=mohamed@unpredictable.fr; helo=outbound.ms.icloud.com","X-Spam_score_int":"-20","X-Spam_score":"-2.1","X-Spam_bar":"--","X-Spam_report":"(-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1,\n DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1,\n SPF_HELO_PASS=-0.001,\n SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no","X-Spam_action":"no action","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"qemu development ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org"},"content":"When running with the Apple vGIC, a minimum PMU is exposed by Hypervisor.framework\nif a valid PMUVer register value is set. That PMU isn't exposed otherwise.\n\nSigned-off-by: Mohamed Mediouni \nReviewed-by: Philippe Mathieu-Daudé \n---\n target/arm/hvf/hvf.c | 19 +++++++++++++++++++\n 1 file changed, 19 insertions(+)","diff":"diff --git a/target/arm/hvf/hvf.c b/target/arm/hvf/hvf.c\nindex 9d64f2e1a5..390a3529ff 100644\n--- a/target/arm/hvf/hvf.c\n+++ b/target/arm/hvf/hvf.c\n@@ -1145,6 +1145,25 @@ static bool hvf_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)\n \n clamp_id_aa64mmfr0_parange_to_ipa_size(&host_isar);\n \n+ /*\n+ * Windows wants at least the PMU's cycles counter to be available.\n+ *\n+ * With kernel-irqchip=off, we \"emulate\" the cycles counter\n+ * in reference to time in QEMU. Having that, even with\n+ * ID_AA64DFR0_EL1.PMUVer = 0 is enough to make Windows happy.\n+ *\n+ * As it's a very inaccurate implementation with its only purpose\n+ * being making Windows boot, expose ID_AA64DFR0_EL1.PMUVer = 0\n+ * when kernel-irqchip=off.\n+ *\n+ * When kernel-irqchip=on *and* ID_AA64DFR0_EL1.PMUVer = 1,\n+ * the OS provides its own PMU emulation, which is currently\n+ * a cycles counter only emulation.\n+ */\n+ if (hvf_irqchip_in_kernel()) {\n+ FIELD_DP64_IDREG(&host_isar, ID_AA64DFR0, PMUVER, 0x1);\n+ }\n+\n ahcf->isar = host_isar;\n \n /*\n","prefixes":["v21","08/15"]}