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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 0360FC43458 for ; Wed, 1 Jul 2026 02:08:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=s+Tz53geg0sl7Fl/scWZtDuIP7JXnIxZZbyAEqDHJJ8=; b=SauypcEy93GXVU pNo6hicX/XuuPsnmRnrpEDlq+WiIPU5LxWKtI9S6Bat5KvytMjRt/QQu8MFx1X3FLTG8pn31pUFpr WrGasXh32xGXa3VtqJaOpoS5HkqCXNoTjAR/iOr1K2uLEuI4K14Em9OMG7ZXlJfrCcDrSetZFWc3i VJjtboTqpdfO5E5UWaGCG3sUKiKxv0nJj4QovVdsRrjW26efyuYKEmjzssG+a1QrhqwJbRp2WMTF6 wTdrFO2EJX2+//S3UAnyb44Vqn4vlnE2hDXBao4LfUs1kimEw5RleELlaUHbar9MHBqiacdkluW28 N2kODIhmmv+MDbFmkqXw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wekNN-00000000UuV-1ZoG; Wed, 01 Jul 2026 02:08:33 +0000 Received: from mail-pl1-x629.google.com ([2607:f8b0:4864:20::629]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wekNG-00000000Un3-39cc for linux-riscv@lists.infradead.org; Wed, 01 Jul 2026 02:08:29 +0000 Received: by mail-pl1-x629.google.com with SMTP id d9443c01a7336-2c9bd2f8bf7so9779115ad.1 for ; Tue, 30 Jun 2026 19:08:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1782871706; x=1783476506; darn=lists.infradead.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=UUgRqFJ2BhFN++AYCVLW2I69ezDqz+uAsqdfUKNMzHE=; b=LQDjgLvpHLl9E5/jSIgDUi5cA7wSLZJ3Qeh/9Nylt9N7OewgkZz3GuPHHo50pnMELT 8NX0Q4piraQ/l8uoxqmQFPv7LQmujfHx1Hw4TSgzqz5GS/Q/ZILGNOCwkHOel6oSa/VQ 8M4XYwntIU72KGMDeYp5gEAHXn67PzfYiogh+mirmoCfQ4Sh2MzHd/FrahAcLmtrlZxO Ujd5w4kzldX7LiYVPvk8dmxC8c5v+eEvK859ufyM7FJcwjE67TcUq3uAfMJU74tdlNiv DxINqP5Im49g54wjfjxyRfMxkcw7OUxzEmF+p92g14BkZA0KTwmJ5rooNI3FiLoSG1Az 4q7A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782871706; x=1783476506; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=UUgRqFJ2BhFN++AYCVLW2I69ezDqz+uAsqdfUKNMzHE=; b=F0+2+9kS9IBnQeiDXQQlx22ZCAEvdAR7BVfzO0vtCaBAGdSfw6xoe3W6QMlQKGxdRq myPJpro+lfxDN3dknuA7m0Nxw1GnVoBPW6hkZuoBkI4p6U8xzXKPsFmvb/h12AuW5QRp JfjKNSxHHQb+tsWI1bcR40adWRwtOMIcVs7RZ1q5PNYSFNUz7mun50J38m7GhihchIKx WVFaqYdODLxXqBiUosu2XSKowMicuIIXkmGsWpMhGO5b7iG3lCbYz6g85Nfm8dQkoI/q DdMDfuQuP1ss4eq03RAhL0/J4/1PpzebKjXbx+J74lBT2uNR7GXYBRGYWO90oPYxSwkt dbDg== X-Gm-Message-State: AOJu0YwMBjy6ql37YKHW6BS4LPUBkHaCJAKO87yXLZbIg+EgGf4Giiiy 9tO7EHfKqDJecWEhl24iZbeXU+LXVmz++W1A49aG+JJRPFuqNurXu30S X-Gm-Gg: AfdE7ckcgoW6BIwQTcQIQ4qoWAa83FG568f0N+r7PT1DL9qdwYT11TdHE+xnHqc3QsJ vE2qSLlbRmbcN1Qtgj5KfcF+X5/Sud74iKR3xnlsC2+uCVVN1B8ECi/FWYLQLA/Q10vnxVQOBv8 2sscjTXkBsoh9K07RsOzgzGoAVsO3ue0gn/J9uT7LmmE4ipEvFDZHlcb5hYaiOhbfl6TboqNb6k JxhAT7GsLR5WP8artDo7UkiNS0mKgIjKqLW+LVXokpr6o/CZKfRV9llP5NK2PMAkoLNqsmWlr0M rLVyYTi9NuemC2PPzYcCC8w26fQC9QdpIke5+8Iu/WBrTqe5BQs7yr7kYtVGaigz/+uMx2tm2sb alJXKLw7CxgElstp4kPqFQ9ugB+hL+aHLVxv+bs/ZeGFVJepNv7TuneccOekyop6jeduAkyIqij 2/gCsOrf2Pknw= X-Received: by 2002:a17:902:e749:b0:2ca:6bb:30fe with SMTP id d9443c01a7336-2ca449fcc45mr29959045ad.20.1782871705882; Tue, 30 Jun 2026 19:08:25 -0700 (PDT) Received: from localhost ([2001:19f0:8000:3e6e:5400:6ff:fe38:3d01]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2ca3828c8e8sm22855905ad.42.2026.06.30.19.08.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 30 Jun 2026 19:08:25 -0700 (PDT) From: Inochi Amaoto To: Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Anup Patel , Atish Patra , Paolo Bonzini , Shuah Khan , Thomas Huth , Sergey Matyukevich , Inochi Amaoto , Andy Chiu , Deepak Gupta Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-kselftest@vger.kernel.org, Yixun Lan , Longbin Li Subject: [PATCH v4 4/8] RISC-V: KVM: Add ssp context save/restore Date: Wed, 1 Jul 2026 10:07:41 +0800 Message-ID: <20260701020746.170157-5-inochiama@gmail.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260701020746.170157-1-inochiama@gmail.com> References: <20260701020746.170157-1-inochiama@gmail.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260630_190827_426839_A7EBD272 X-CRM114-Status: GOOD ( 18.87 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Add ssp context save/restore for guest VCPUs and also add it to the ONE_REG interface to allow its access from user space. Signed-off-by: Inochi Amaoto --- arch/riscv/include/asm/kvm_host.h | 7 ++++ arch/riscv/include/uapi/asm/kvm.h | 8 ++++ arch/riscv/kvm/vcpu.c | 6 +++ arch/riscv/kvm/vcpu_onereg.c | 66 ++++++++++++++++++++++++++++++- 4 files changed, 85 insertions(+), 2 deletions(-) diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h index 60017ceec9d2..e5ed3b0e5a55 100644 --- a/arch/riscv/include/asm/kvm_host.h +++ b/arch/riscv/include/asm/kvm_host.h @@ -163,6 +163,10 @@ struct kvm_vcpu_smstateen_csr { unsigned long sstateen0; }; +struct kvm_vcpu_zicfiss_csr { + unsigned long ssp; +}; + struct kvm_vcpu_reset_state { spinlock_t lock; unsigned long pc; @@ -203,6 +207,9 @@ struct kvm_vcpu_arch { /* CPU Smstateen CSR context of Guest VCPU */ struct kvm_vcpu_smstateen_csr smstateen_csr; + /* CPU Zicfiss CSR context of Guest VCPU */ + struct kvm_vcpu_zicfiss_csr zicfiss_csr; + /* CPU reset state of Guest VCPU */ struct kvm_vcpu_reset_state reset_state; diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h index a27de850fa4c..fd4c81697617 100644 --- a/arch/riscv/include/uapi/asm/kvm.h +++ b/arch/riscv/include/uapi/asm/kvm.h @@ -102,6 +102,11 @@ struct kvm_riscv_smstateen_csr { unsigned long sstateen0; }; +/* Zicfiss CSR for KVM_GET_ONE_REG and KVM_SET_ONE_REG */ +struct kvm_riscv_zicfiss_csr { + unsigned long ssp; +}; + /* TIMER registers for KVM_GET_ONE_REG and KVM_SET_ONE_REG */ struct kvm_riscv_timer { __u64 frequency; @@ -266,12 +271,15 @@ struct kvm_riscv_sbi_fwft { #define KVM_REG_RISCV_CSR_GENERAL (0x0 << KVM_REG_RISCV_SUBTYPE_SHIFT) #define KVM_REG_RISCV_CSR_AIA (0x1 << KVM_REG_RISCV_SUBTYPE_SHIFT) #define KVM_REG_RISCV_CSR_SMSTATEEN (0x2 << KVM_REG_RISCV_SUBTYPE_SHIFT) +#define KVM_REG_RISCV_CSR_ZICFISS (0x3 << KVM_REG_RISCV_SUBTYPE_SHIFT) #define KVM_REG_RISCV_CSR_REG(name) \ (offsetof(struct kvm_riscv_csr, name) / sizeof(unsigned long)) #define KVM_REG_RISCV_CSR_AIA_REG(name) \ (offsetof(struct kvm_riscv_aia_csr, name) / sizeof(unsigned long)) #define KVM_REG_RISCV_CSR_SMSTATEEN_REG(name) \ (offsetof(struct kvm_riscv_smstateen_csr, name) / sizeof(unsigned long)) +#define KVM_REG_RISCV_CSR_ZICFISS_REG(name) \ + (offsetof(struct kvm_riscv_zicfiss_csr, name) / sizeof(unsigned long)) /* Timer registers are mapped as type 4 */ #define KVM_REG_RISCV_TIMER (0x04 << KVM_REG_RISCV_TYPE_SHIFT) diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c index cf6e231e76e2..1c2775a4834e 100644 --- a/arch/riscv/kvm/vcpu.c +++ b/arch/riscv/kvm/vcpu.c @@ -720,6 +720,7 @@ static void kvm_riscv_update_hvip(struct kvm_vcpu *vcpu) static __always_inline void kvm_riscv_vcpu_swap_in_guest_state(struct kvm_vcpu *vcpu) { + struct kvm_vcpu_zicfiss_csr *zicficsr = &vcpu->arch.zicfiss_csr; struct kvm_vcpu_smstateen_csr *smcsr = &vcpu->arch.smstateen_csr; struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; @@ -727,10 +728,13 @@ static __always_inline void kvm_riscv_vcpu_swap_in_guest_state(struct kvm_vcpu * vcpu->arch.host_senvcfg = csr_swap(CSR_SENVCFG, csr->senvcfg); if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN)) vcpu->arch.host_sstateen0 = csr_swap(CSR_SSTATEEN0, smcsr->sstateen0); + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_ZICFISS)) + csr_write(CSR_SSP, zicficsr->ssp); } static __always_inline void kvm_riscv_vcpu_swap_in_host_state(struct kvm_vcpu *vcpu) { + struct kvm_vcpu_zicfiss_csr *zicficsr = &vcpu->arch.zicfiss_csr; struct kvm_vcpu_smstateen_csr *smcsr = &vcpu->arch.smstateen_csr; struct kvm_vcpu_csr *csr = &vcpu->arch.guest_csr; @@ -738,6 +742,8 @@ static __always_inline void kvm_riscv_vcpu_swap_in_host_state(struct kvm_vcpu *v csr->senvcfg = csr_swap(CSR_SENVCFG, vcpu->arch.host_senvcfg); if (riscv_has_extension_unlikely(RISCV_ISA_EXT_SMSTATEEN)) smcsr->sstateen0 = csr_swap(CSR_SSTATEEN0, vcpu->arch.host_sstateen0); + if (riscv_has_extension_unlikely(RISCV_ISA_EXT_ZICFISS)) + zicficsr->ssp = csr_swap(CSR_SSP, 0); } /* diff --git a/arch/riscv/kvm/vcpu_onereg.c b/arch/riscv/kvm/vcpu_onereg.c index bb920e8923c9..bd59aebc8b2e 100644 --- a/arch/riscv/kvm/vcpu_onereg.c +++ b/arch/riscv/kvm/vcpu_onereg.c @@ -355,6 +355,44 @@ static int kvm_riscv_vcpu_smstateen_get_csr(struct kvm_vcpu *vcpu, return 0; } +static inline int kvm_riscv_vcpu_zicfiss_set_csr(struct kvm_vcpu *vcpu, + unsigned long reg_num, + unsigned long reg_val) +{ + struct kvm_vcpu_zicfiss_csr *csr = &vcpu->arch.zicfiss_csr; + unsigned long regs_max = sizeof(struct kvm_vcpu_zicfiss_csr) / + sizeof(unsigned long); + + if (!riscv_isa_extension_available(vcpu->arch.isa, ZICFISS)) + return -ENOENT; + if (reg_num >= regs_max) + return -ENOENT; + + reg_num = array_index_nospec(reg_num, regs_max); + + ((unsigned long *)csr)[reg_num] = reg_val; + return 0; +} + +static int kvm_riscv_vcpu_zicfiss_get_csr(struct kvm_vcpu *vcpu, + unsigned long reg_num, + unsigned long *out_val) +{ + struct kvm_vcpu_zicfiss_csr *csr = &vcpu->arch.zicfiss_csr; + unsigned long regs_max = sizeof(struct kvm_vcpu_zicfiss_csr) / + sizeof(unsigned long); + + if (!riscv_isa_extension_available(vcpu->arch.isa, ZICFISS)) + return -ENOENT; + if (reg_num >= regs_max) + return -ENOENT; + + reg_num = array_index_nospec(reg_num, regs_max); + + *out_val = ((unsigned long *)csr)[reg_num]; + return 0; +} + static int kvm_riscv_vcpu_get_reg_csr(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) { @@ -381,6 +419,9 @@ static int kvm_riscv_vcpu_get_reg_csr(struct kvm_vcpu *vcpu, case KVM_REG_RISCV_CSR_SMSTATEEN: rc = kvm_riscv_vcpu_smstateen_get_csr(vcpu, reg_num, ®_val); break; + case KVM_REG_RISCV_CSR_ZICFISS: + rc = kvm_riscv_vcpu_zicfiss_get_csr(vcpu, reg_num, ®_val); + break; default: rc = -ENOENT; break; @@ -423,6 +464,9 @@ static int kvm_riscv_vcpu_set_reg_csr(struct kvm_vcpu *vcpu, case KVM_REG_RISCV_CSR_SMSTATEEN: rc = kvm_riscv_vcpu_smstateen_set_csr(vcpu, reg_num, reg_val); break; + case KVM_REG_RISCV_CSR_ZICFISS: + rc = kvm_riscv_vcpu_zicfiss_set_csr(vcpu, reg_num, reg_val); + break; default: rc = -ENOENT; break; @@ -688,7 +732,7 @@ static int copy_csr_reg_indices(const struct kvm_vcpu *vcpu, u64 __user *uindices) { int n1 = sizeof(struct kvm_riscv_csr) / sizeof(unsigned long); - int n2 = 0, n3 = 0; + int n2 = 0, n3 = 0, n4 = 0; /* copy general csr regs */ for (int i = 0; i < n1; i++) { @@ -740,7 +784,25 @@ static int copy_csr_reg_indices(const struct kvm_vcpu *vcpu, } } - return n1 + n2 + n3; + /* copy Zicfiss csr regs */ + if (riscv_isa_extension_available(vcpu->arch.isa, ZICFISS)) { + n4 = sizeof(struct kvm_riscv_zicfiss_csr) / sizeof(unsigned long); + + for (int i = 0; i < n4; i++) { + u64 size = IS_ENABLED(CONFIG_32BIT) ? + KVM_REG_SIZE_U32 : KVM_REG_SIZE_U64; + u64 reg = KVM_REG_RISCV | size | KVM_REG_RISCV_CSR | + KVM_REG_RISCV_CSR_ZICFISS | i; + + if (uindices) { + if (put_user(reg, uindices)) + return -EFAULT; + uindices++; + } + } + } + + return n1 + n2 + n3 + n4; } static inline unsigned long num_timer_regs(void) -- 2.55.0 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv