From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 541A52E6CA6 for ; Mon, 30 Mar 2026 14:50:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774882224; cv=none; b=XO3s+la/V2Pa1z/mif47e778N4/E39SfieYbeR3OGd0e034soH2gNqJTmlh5W9s48PKcRxvcu6GHIUtknKOCFovRyGcDXKcDTvGafow+WE01K2He2xGo9XvoT+lMSnxNYOw0/puYoZFIyZOD5mu3pjYmc4W5dJmOKn84AMqM2f8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774882224; c=relaxed/simple; bh=hX7WpuSzVjKhvamwyREgD0HgIZ7/OljygrMTOLlyXWM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Qx4RgopLvhmvkUyelXEEKpTjZXa5uTdh5GINbsHWHMcgeBVcingG/w5AQwV7xdZaCQs1bVK9jLFQlRjvfYltgtOdqmLx6l84pT8VQAFApsFUmuMLOHMtwD0FnxvAqzlkSYcpUMMZZh70wvIy2mysYDI9CBe+KNBQxx/glOnqFiM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kcPgxR+H; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="kcPgxR+H" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5A920C2BCB1; Mon, 30 Mar 2026 14:50:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774882224; bh=hX7WpuSzVjKhvamwyREgD0HgIZ7/OljygrMTOLlyXWM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kcPgxR+Hpkg9KnguSLuM/QRtZIwQHCiNhRenUXgaVG/Mmz9o7P4ycBY6gfq0fnI+K YSGvKmuKXfU8MWbJzm+aEMovK11QewArEoErTDM9iSouNC6zuqxhnj2pBLrHRL3QQh T3s3m2yw8wZpjEa0Elr15f9pJxFIZUtznVEyCoAVyhl9jl+zyVIW+/HHiOTcbwQmC5 lY3mtON5/BHSAf4SVftck5VHmJrKWt/AsdOaM5XaPL2L7WUdyQjQIF+CDJX+l5AK7X tflGVDdDGd/WgmhZOQ8mwVjH1J6gwTj3Gyg0V72gB7+KxLsQKRKYmaVK+zVCTiyBdd cKsD5kQ0rCojA== From: Will Deacon To: kvmarm@lists.linux.dev Cc: linux-arm-kernel@lists.infradead.org, Will Deacon , Marc Zyngier , Oliver Upton , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Quentin Perret , Fuad Tabba , Vincent Donnefort , Mostafa Saleh , Alexandru Elisei Subject: [PATCH v5 28/38] KVM: arm64: Add hvc handler at EL2 for hypercalls from protected VMs Date: Mon, 30 Mar 2026 15:48:29 +0100 Message-ID: <20260330144841.26181-29-will@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260330144841.26181-1-will@kernel.org> References: <20260330144841.26181-1-will@kernel.org> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Add a hypercall handler at EL2 for hypercalls originating from protected VMs. For now, this implements only the FEATURES and MEMINFO calls, but subsequent patches will implement the SHARE and UNSHARE functions necessary for virtio. Unhandled hypercalls (including PSCI) are passed back to the host. Reviewed-by: Vincent Donnefort Tested-by: Fuad Tabba Tested-by: Mostafa Saleh Signed-off-by: Will Deacon --- arch/arm64/kvm/hyp/include/nvhe/pkvm.h | 1 + arch/arm64/kvm/hyp/nvhe/pkvm.c | 37 ++++++++++++++++++++++++++ arch/arm64/kvm/hyp/nvhe/switch.c | 1 + 3 files changed, 39 insertions(+) diff --git a/arch/arm64/kvm/hyp/include/nvhe/pkvm.h b/arch/arm64/kvm/hyp/include/nvhe/pkvm.h index a5a7bb453f3e..c904647d2f76 100644 --- a/arch/arm64/kvm/hyp/include/nvhe/pkvm.h +++ b/arch/arm64/kvm/hyp/include/nvhe/pkvm.h @@ -88,6 +88,7 @@ struct pkvm_hyp_vm *get_pkvm_hyp_vm(pkvm_handle_t handle); struct pkvm_hyp_vm *get_np_pkvm_hyp_vm(pkvm_handle_t handle); void put_pkvm_hyp_vm(struct pkvm_hyp_vm *hyp_vm); +bool kvm_handle_pvm_hvc64(struct kvm_vcpu *vcpu, u64 *exit_code); bool kvm_handle_pvm_sysreg(struct kvm_vcpu *vcpu, u64 *exit_code); bool kvm_handle_pvm_restricted(struct kvm_vcpu *vcpu, u64 *exit_code); void kvm_init_pvm_id_regs(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c index cdeefe3d74ff..1f184c4994fa 100644 --- a/arch/arm64/kvm/hyp/nvhe/pkvm.c +++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c @@ -4,6 +4,8 @@ * Author: Fuad Tabba */ +#include + #include #include @@ -971,3 +973,38 @@ int __pkvm_finalize_teardown_vm(pkvm_handle_t handle) hyp_spin_unlock(&vm_table_lock); return err; } +/* + * Handler for protected VM HVC calls. + * + * Returns true if the hypervisor has handled the exit (and control + * should return to the guest) or false if it hasn't (and the handling + * should be performed by the host). + */ +bool kvm_handle_pvm_hvc64(struct kvm_vcpu *vcpu, u64 *exit_code) +{ + u64 val[4] = { SMCCC_RET_INVALID_PARAMETER }; + bool handled = true; + + switch (smccc_get_function(vcpu)) { + case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID: + val[0] = BIT(ARM_SMCCC_KVM_FUNC_FEATURES); + val[0] |= BIT(ARM_SMCCC_KVM_FUNC_HYP_MEMINFO); + break; + case ARM_SMCCC_VENDOR_HYP_KVM_HYP_MEMINFO_FUNC_ID: + if (smccc_get_arg1(vcpu) || + smccc_get_arg2(vcpu) || + smccc_get_arg3(vcpu)) { + break; + } + + val[0] = PAGE_SIZE; + break; + default: + /* Punt everything else back to the host, for now. */ + handled = false; + } + + if (handled) + smccc_set_retval(vcpu, val[0], val[1], val[2], val[3]); + return handled; +} diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c index 779089e42681..51bd88dc6012 100644 --- a/arch/arm64/kvm/hyp/nvhe/switch.c +++ b/arch/arm64/kvm/hyp/nvhe/switch.c @@ -190,6 +190,7 @@ static const exit_handler_fn hyp_exit_handlers[] = { static const exit_handler_fn pvm_exit_handlers[] = { [0 ... ESR_ELx_EC_MAX] = NULL, + [ESR_ELx_EC_HVC64] = kvm_handle_pvm_hvc64, [ESR_ELx_EC_SYS64] = kvm_handle_pvm_sys64, [ESR_ELx_EC_SVE] = kvm_handle_pvm_restricted, [ESR_ELx_EC_FP_ASIMD] = kvm_hyp_handle_fpsimd, -- 2.53.0.1018.g2bb0e51243-goog