From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f53.google.com (mail-wm1-f53.google.com [209.85.128.53]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 439004C92 for ; Tue, 6 Jan 2026 15:52:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.53 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767714776; cv=none; b=Bf4KvuZDATRa35yQM88iLSxdBQK9bP45OJY0Z7ig1M3sK4UbrVIMY+N9JXZPBaeuFS6Iq0U6fCH9N8/znn/YFYhAgLyNxUUSvTg45nZ3sbLolRSDvfK3xAIPi2qFTwIEzw9UZaX+UXmiek4ePyY7MmX5PIivQKil9a61jN6OLio= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767714776; c=relaxed/simple; bh=bCtVsknzzZlL7c6hHCrnnwdsXQ+7Eh4/XZfEWm+iadM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=h2JAxNPTBH+MHaGWTbQX64MtSsCE6fpNlFkY+XmR5uRwLmXauw/FgiExAIedS8CT64TwL5E7Qv+kHMxgYGNfeQegqVNmHLYnFEuqJHkGDdEzTC9VUE8IyYMsX2RDt2IVn/a3oWInmJ4Pr78c6Ha2OyQ+b5o6EhYaaoTPE9Hwog0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=0RNT4duK; arc=none smtp.client-ip=209.85.128.53 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="0RNT4duK" Received: by mail-wm1-f53.google.com with SMTP id 5b1f17b1804b1-47d182a8c6cso6713115e9.1 for ; Tue, 06 Jan 2026 07:52:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1767714773; x=1768319573; darn=lists.linux.dev; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=REzMItOKRjoF4vczIgVji7C5aDimDWmguKzGPV8mrrY=; b=0RNT4duKcFAGYC96Pg92ttg1sryvWdUJ8aMi4aHkFtILbi6uo5PqsP9t64e5yiex5i P6txI+2y38wKNnoUiLy3d/TUbRa8DCRjBEbEr4TjXzc4McHkV/sZz29jkcyYRvFbhNRm Dvdp8DzW57khOIvZ9aalstCjdGUgIypWIfteNq3E6k6oNnHwn32VXGL8mYUZrYZZJxJe dpecRL3Aa2wt0X00sKVVZ/UznobVLfF9fFWiLKgh8dzJBWiusy/C79/ot6NTuuwt8JZ3 vloiAqeMNAlZuy/bfSWYxaDnHVYkdFvgRcaNrVQ5nel4wDNnZnnF78Uf2yoXN6za8LH8 w0FA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1767714773; x=1768319573; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=REzMItOKRjoF4vczIgVji7C5aDimDWmguKzGPV8mrrY=; b=KJgIxIPcbSVI0mXlGrM3P9PODqm7SBax2oGF/IZvUXt9mVZhJZV1GTaCtbi/hBTC0K rG4h9oB45ChjUYG24kGKcWTkT9V4SSdtU6341hkgfLOxKVAtGKDwymnKe9l8hU0l12ds ghF5B/X+ZCJQG6SQlHoRIxTpXCKc/4rD4nON+sxtKRkDASwx5MXt6E+C4wvrMPtPI/cL z7yzOmVbOjY4kVdudU1hkFHypYhj4MbqSHOge5I+rM4pc9gqg8cIGfrTx/eeDN/WCm0R xfAoPdTRqP7KT9gmWgOpQIwNPiEdsjfkdbEIIX/EzXaaU3BHIjpCK2C1Np0647b6Dlqr 6WDA== X-Gm-Message-State: AOJu0Yx7nkdKl9YAXEbz4xJ1Y7MCMU6VgIPW+S+9GoeQNZoCoJMOTfMw hOjhtIvEUtctAR2wrYQ5cG+N8b9LvMOvwqaPCp9CRzQAqQLuhoA5rT2sjRn2YdvQ2A== X-Gm-Gg: AY/fxX6NjilM4SXlMWfiOY4SHJv2VTDXPzhTEoV5kfA1KBs277HGL477YG/Ek0Io4e4 9lDB3MVJL7TKrh+merGKvk3ELe2xJdUSIP2u7nX3412mNCK0/hy+CP6hocwJYGGH2dDt/W/JpCm oJjwi7mcVZod+UKMgT5c6brsPy5Nr19zI5U33XoDOo6snWrkUNiQD3hmHWNxmKzBivx0vGvD1IW EJBDefKnAeNYuim62H+oOy+IDMvbgkrmitCICKomQT13Je0aEEPPDIJHQRsEjkivdxnjo37/Ssz saD0Z5L7B6dP8ZiqqDKHoRtEzgQoSqrONZot/JtSo7j+7qUMuM9kNn9Nwl/YdXG8v6AxLgBKK0Z ILs+ezNqzeq1lkvH0AtIcJkaI7NOt02LLdtqXCXL9Ezp+EaIGPMQ3LLB8eN54xdZm+g4mGyl+04 UVRJpz+7J+lPmJuv+pHTZrC/ja/I141qdURTJ0bdDKvpBo9+dfrw== X-Google-Smtp-Source: AGHT+IEMfxjN3FxPle45sdSpE9DcCNTEP+ANJOmomnv50tX3o9Ne4hQ0H16mskrmCeiSoTeIbY2MCQ== X-Received: by 2002:a05:600c:34c6:b0:47d:3ffa:980e with SMTP id 5b1f17b1804b1-47d7f09b759mr32272115e9.28.1767714772302; Tue, 06 Jan 2026 07:52:52 -0800 (PST) Received: from google.com (44.145.34.34.bc.googleusercontent.com. [34.34.145.44]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-432bd0e199bsm5154284f8f.16.2026.01.06.07.52.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 06 Jan 2026 07:52:51 -0800 (PST) Date: Tue, 6 Jan 2026 15:52:48 +0000 From: Vincent Donnefort To: Will Deacon Cc: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Marc Zyngier , Oliver Upton , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Quentin Perret , Fuad Tabba , Mostafa Saleh Subject: Re: [PATCH 23/30] KVM: arm64: Add hvc handler at EL2 for hypercalls from protected VMs Message-ID: References: <20260105154939.11041-1-will@kernel.org> <20260105154939.11041-24-will@kernel.org> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260105154939.11041-24-will@kernel.org> On Mon, Jan 05, 2026 at 03:49:31PM +0000, Will Deacon wrote: > 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. > > Signed-off-by: Will Deacon Reviewed-by: Vincent Donnefort > --- > 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 df340de59eed..5cdec49e989b 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 > > @@ -934,3 +936,38 @@ 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 d3b9ec8a7c28..b62e25e8bb7e 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, > -- > 2.52.0.351.gbe84eed79e-goog >