From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DF40826E716 for ; Wed, 3 Sep 2025 11:15:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756898159; cv=none; b=K4G70byrUkpBFQN5FcvJW/ICKqwohvx4BO9Y+MssOmw5nRbdEuMIYCF9TawRXh701Q8r2q8A4DH/D2bjPW4ujsIJ0k+37Ol1JdUjOgam2QeN5ttU4feGdBM4IFz0ZmRcVBj1Jz6Kl8YEvCGUzMoxWg/F064eXmsCYNUypRR1PqM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756898159; c=relaxed/simple; bh=O5Kl27XB553N7cmeBmXq/uiaTLYFFfTmRY6zD5Qm2IA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=ShccA6KdbQVXcw7oJnGz0TI+n0yfO2FmEuUAiljVFUdRk2oJrSegyjaYJokR0qZD1RLvEuxGLV7C+gZjnqxMFZyIm3yO9g8D4BHyGSw2xLMJcGQbH8dDzvZyizLZlId+c+Xqkfc3suqo7BnABdJekfoEMTTNj6a9wknvJ/rmBoI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=YwythlQV; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="YwythlQV" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1756898156; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=kVBqAzXRtaGdVaqdIdbidkD/s0lTNKoOEws6COnY9ko=; b=YwythlQVxvQcs54IB9cQyVHcXm5eyuNI4507+mzd5drvfaWRPaMOKTLmw+X/HK3nTHchSz jsEiPxepjB/9XaDgg9ujIe29NodO6NO22IJgrXKuwjyttwmtya6bNSv7pvrXnxVMl0WJVa krtQkNacD4ir+5TVN53RcOotRW8MV9M= Received: from mail-pf1-f197.google.com (mail-pf1-f197.google.com [209.85.210.197]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-108-S7lGklGDNUqoyZxlmr3I_g-1; Wed, 03 Sep 2025 07:15:55 -0400 X-MC-Unique: S7lGklGDNUqoyZxlmr3I_g-1 X-Mimecast-MFC-AGG-ID: S7lGklGDNUqoyZxlmr3I_g_1756898155 Received: by mail-pf1-f197.google.com with SMTP id d2e1a72fcca58-7724877cd7cso3888127b3a.1 for ; Wed, 03 Sep 2025 04:15:55 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1756898154; x=1757502954; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=kVBqAzXRtaGdVaqdIdbidkD/s0lTNKoOEws6COnY9ko=; b=On9J7DwHozci92PC0/vQvbmsbpoAfyLHiQAvAMPs8bZl/jvc+AMTzsSIhcg1E2sb2Q qnDaDgNteXsmJ0qDGPw0I/FezSxZEpWFYcoWRXKYcCgHfs10eBI5l2pw94PFt+w21OaP G4Q/DrCR4hmDHgJTM4aY+UwkxwqHnKxrbeAdvCvXXquGUwOiCb5wvtwdqkWQX4TwfVwj Th1U7gK5rxKBT9MgjLLVljmGKEj3WT5l+lPa2x2OUPWDTOLeSfPu7i1hexRVDOFfFxZI wY4ZyKRPdpPl8ofkkvDndPzRb6Ec522ZWi4DdERfYF13KbQjUjJdfYPZnplrJKgNMhty OVNw== X-Forwarded-Encrypted: i=1; AJvYcCUtgxIh8mUfIE3eu8y73yqUhTX7FMrLABvqjq3IaO4Tq5EXJyrCknq80rU20HjsQBxKD9qq+qI=@lists.linux.dev X-Gm-Message-State: AOJu0YwTrZgTe3OvSldLqPK71drfGghDm72/3g1J3xsijybhJruABRsz I+GUHpuo4pUGu2USC9qh3l0YE+u+ISYFsAHH1YzOoXOLN3vdGDbBoWeiJMbwXHKI0611U8d0WHB 6PwXoRixy4A4DCIPSWrSnHxWcGWFfN4YSjH5laejnDUwilXwJVkfvXHFx310MiZrkjQ== X-Gm-Gg: ASbGncstVj5lcxeV6OaOO2wcBg2PPl0NF9BQSrUeeqbJDIDaQpQiq/Ezn52uJ3WnChO qK4tfJGsR9umoDNGZDFZdohL2rzZ3gXijDbyKRDHuhW72bEhsr6bwD5wLctpeQIquD1zx1xM+BA ksACEEu3muEkXEm0I+0n6y+bMq1vQoCEvE8Qmg8DkFX6ss9jQLyRw6z4zaZYXPhFa4mM3HBWRsA bHgi+zQe7KvblQyLL1kuVE2DjibfVLZWI3awt1MGrNlmrUp4v9MrY0XVYp3S4Z1z3D0Mdd/RBt1 uF77U/K3pi5f61Gdp0NEy5ISr3Gh0I0oosChSL3lV2Ri4xrd2sPRiVR5vBKocF8RZUXlLZMi/yO b8whB X-Received: by 2002:a05:6a00:2d13:b0:772:2fad:ff64 with SMTP id d2e1a72fcca58-7723e257daamr16145022b3a.8.1756898154155; Wed, 03 Sep 2025 04:15:54 -0700 (PDT) X-Google-Smtp-Source: AGHT+IEehFXhizd/XBGs6lPLajyy1rp0g+vzzGOhiFu//IuUVahDT7Y1/d6xBov7/G/ROyWBDy0Hlg== X-Received: by 2002:a05:6a00:2d13:b0:772:2fad:ff64 with SMTP id d2e1a72fcca58-7723e257daamr16144978b3a.8.1756898153626; Wed, 03 Sep 2025 04:15:53 -0700 (PDT) Received: from [192.168.68.51] (n175-34-62-5.mrk21.qld.optusnet.com.au. [175.34.62.5]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-7722a269e9csm16651516b3a.17.2025.09.03.04.15.45 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 03 Sep 2025 04:15:52 -0700 (PDT) Message-ID: <0481109b-769f-464b-aa72-ad6e07bdfa78@redhat.com> Date: Wed, 3 Sep 2025 21:15:43 +1000 Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v10 05/43] arm64: RME: Check for RME support at KVM init To: Steven Price , kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , Suzuki K Poulose , Zenghui Yu , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Joey Gouly , Alexandru Elisei , Christoffer Dall , Fuad Tabba , linux-coco@lists.linux.dev, Ganapatrao Kulkarni , Shanker Donthineni , Alper Gun , "Aneesh Kumar K . V" , Emi Kisanuki , Vishal Annapurve References: <20250820145606.180644-1-steven.price@arm.com> <20250820145606.180644-6-steven.price@arm.com> From: Gavin Shan In-Reply-To: <20250820145606.180644-6-steven.price@arm.com> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: jZecKbsInlj1I7EF2HA-vZRo05_VMkKtOaWT-bcmBaQ_1756898155 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 8/21/25 12:55 AM, Steven Price wrote: > Query the RMI version number and check if it is a compatible version. A > static key is also provided to signal that a supported RMM is available. > > Functions are provided to query if a VM or VCPU is a realm (or rec) > which currently will always return false. > > Later patches make use of struct realm and the states as the ioctls > interfaces are added to support realm and REC creation and destruction. > > Reviewed-by: Gavin Shan > Reviewed-by: Suzuki K Poulose > Signed-off-by: Steven Price > --- > Changes since v8: > * No need to guard kvm_init_rme() behind 'in_hyp_mode'. > Changes since v6: > * Improved message for an unsupported RMI ABI version. > Changes since v5: > * Reword "unsupported" message from "host supports" to "we want" to > clarify that 'we' are the 'host'. > Changes since v2: > * Drop return value from kvm_init_rme(), it was always 0. > * Rely on the RMM return value to identify whether the RSI ABI is > compatible. > --- > arch/arm64/include/asm/kvm_emulate.h | 18 +++++++++ > arch/arm64/include/asm/kvm_host.h | 4 ++ > arch/arm64/include/asm/kvm_rme.h | 56 ++++++++++++++++++++++++++++ > arch/arm64/include/asm/virt.h | 1 + > arch/arm64/kvm/Makefile | 2 +- > arch/arm64/kvm/arm.c | 5 +++ > arch/arm64/kvm/rme.c | 56 ++++++++++++++++++++++++++++ > 7 files changed, 141 insertions(+), 1 deletion(-) > create mode 100644 arch/arm64/include/asm/kvm_rme.h > create mode 100644 arch/arm64/kvm/rme.c > [...] > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > index 888f7c7abf54..76177c56f1ef 100644 > --- a/arch/arm64/kvm/arm.c > +++ b/arch/arm64/kvm/arm.c > @@ -40,6 +40,7 @@ > #include > #include > #include > +#include > #include > Nit: The header file has been included to and , which has been included to arm.c. So this explicit inclusion can be dropped. > #include > @@ -59,6 +60,8 @@ enum kvm_wfx_trap_policy { > static enum kvm_wfx_trap_policy kvm_wfi_trap_policy __read_mostly = KVM_WFX_NOTRAP_SINGLE_TASK; > static enum kvm_wfx_trap_policy kvm_wfe_trap_policy __read_mostly = KVM_WFX_NOTRAP_SINGLE_TASK; > > +DEFINE_STATIC_KEY_FALSE(kvm_rme_is_available); > + > DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector); > > DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_base); > @@ -2836,6 +2839,8 @@ static __init int kvm_arm_init(void) > > in_hyp_mode = is_kernel_in_hyp_mode(); > > + kvm_init_rme(); > + > if (cpus_have_final_cap(ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE) || > cpus_have_final_cap(ARM64_WORKAROUND_1508412)) > kvm_info("Guests without required CPU erratum workarounds can deadlock system!\n" \ > diff --git a/arch/arm64/kvm/rme.c b/arch/arm64/kvm/rme.c > new file mode 100644 > index 000000000000..67cf2d94cb2d > --- /dev/null > +++ b/arch/arm64/kvm/rme.c > @@ -0,0 +1,56 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (C) 2023 ARM Ltd. > + */ > + > +#include > + > +#include > +#include > + > +static int rmi_check_version(void) > +{ > + struct arm_smccc_res res; > + unsigned short version_major, version_minor; > + unsigned long host_version = RMI_ABI_VERSION(RMI_ABI_MAJOR_VERSION, > + RMI_ABI_MINOR_VERSION); > + > + arm_smccc_1_1_invoke(SMC_RMI_VERSION, host_version, &res); > + > + if (res.a0 == SMCCC_RET_NOT_SUPPORTED) > + return -ENXIO; > + > + version_major = RMI_ABI_VERSION_GET_MAJOR(res.a1); > + version_minor = RMI_ABI_VERSION_GET_MINOR(res.a1); > + > + if (res.a0 != RMI_SUCCESS) { > + unsigned short high_version_major, high_version_minor; > + > + high_version_major = RMI_ABI_VERSION_GET_MAJOR(res.a2); > + high_version_minor = RMI_ABI_VERSION_GET_MINOR(res.a2); > + > + kvm_err("Unsupported RMI ABI (v%d.%d - v%d.%d) we want v%d.%d\n", > + version_major, version_minor, > + high_version_major, high_version_minor, > + RMI_ABI_MAJOR_VERSION, > + RMI_ABI_MINOR_VERSION); > + return -ENXIO; > + } > + > + kvm_info("RMI ABI version %d.%d\n", version_major, version_minor); > + > + return 0; > +} > + > +void kvm_init_rme(void) > +{ > + if (PAGE_SIZE != SZ_4K) > + /* Only 4k page size on the host is supported */ > + return; Nit: The comment can be moved before the check, something like below. Otherwise, {} is needed here. /* Only 4kB page size is supported */ if (PAGE_SIZE != SZ_4K) return; > + > + if (rmi_check_version()) > + /* Continue without realm support */ > + return; Nit: same as above. > + > + /* Future patch will enable static branch kvm_rme_is_available */ > +} Thanks, Gavin