From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 82F9026AE5; Mon, 30 Mar 2026 10:58:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774868293; cv=none; b=JnUTnOpJy7wzyIXafe3ji21bBpns8Acrzjt8XlDLp3V1q5mbliLiVfDUELuzJW0sBSk7hgAY+ez3H3Lo7vbQgV8Q+D6wTTZ9KNPv8VwrAiqrgMP2oIml6ls/6bC8PLI1orLa5thldkECiEAjtm8s/KzzRIiFLusj09oHLbFe4jo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774868293; c=relaxed/simple; bh=mONBCtbmbPff0A3dabS2nwwbs9ct9e5u1BA9P4VrR5c=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=JtqPYMoRSgarA0T9Zp3OjKx6WJZNJzaHy6NVs1bZacXwhyB7Ef3erMf2q6QSlPjFrrvf5wGBVDFT7o5+JkRMtLMFFYYG7MHaCNLDNBiRDz3td7nZ42E8QTAQwwUIcbtJurphoiI5iO4AACt1w2YSEJKGH3aehKF/s2eY7Uba3Fs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=O7cDYZFH; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="O7cDYZFH" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6B3351C01; Mon, 30 Mar 2026 03:58:02 -0700 (PDT) Received: from [10.57.13.56] (unknown [10.57.13.56]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0D4A13F915; Mon, 30 Mar 2026 03:58:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1774868288; bh=mONBCtbmbPff0A3dabS2nwwbs9ct9e5u1BA9P4VrR5c=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=O7cDYZFHXEzuxS8cQTR9gIEc1iShETlDG4sQ/XazlOkV5Mry75J+eICB0NiKv1k8b vleJTNMbKT4ovAUQsnrDoU09OL258RoFomntVNwjHtTcFp2F0bgoQYw7qTcvmA15iV 0fBuYUY/dJ4ycbTn4G3WwWoi/4cWPdqxRX0+03BQ= Message-ID: <053a048d-bcb7-46ef-a4c2-c5d0c84a3177@arm.com> Date: Mon, 30 Mar 2026 11:58:03 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v13 34/48] arm64: RMI: support RSI_HOST_CALL Content-Language: en-GB To: Steven Price , kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Joey Gouly , Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , Zenghui Yu , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Alexandru Elisei , Christoffer Dall , Fuad Tabba , linux-coco@lists.linux.dev, Ganapatrao Kulkarni , Gavin Shan , Shanker Donthineni , Alper Gun , "Aneesh Kumar K . V" , Emi Kisanuki , Vishal Annapurve References: <20260318155413.793430-1-steven.price@arm.com> <20260318155413.793430-35-steven.price@arm.com> From: Suzuki K Poulose In-Reply-To: <20260318155413.793430-35-steven.price@arm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 18/03/2026 15:53, Steven Price wrote: > From: Joey Gouly > > Forward RSI_HOST_CALLS to KVM's HVC handler. Minor nit: Please could we add a line or two, explaining what RSI_HOST_CALL is ? e.g.: Realm's can talk to the hypervisor using the RSI_HOST_CALL, which the RMM forwards to the KVM. Handle them as regular hypercalls. Suzuki > > Signed-off-by: Joey Gouly > Signed-off-by: Steven Price > Reviewed-by: Gavin Shan > --- > Changes since v7: > * Avoid turning a negative return from kvm_smccc_call_handler() into a > error response to the guest. Instead propogate the error back to user > space. > Changes since v4: > * Setting GPRS is now done by kvm_rec_enter() rather than > rec_exit_host_call() (see previous patch - arm64: RME: Handle realm > enter/exit). This fixes a bug where the registers set by user space > were being ignored. > --- > arch/arm64/kvm/rmi-exit.c | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/arch/arm64/kvm/rmi-exit.c b/arch/arm64/kvm/rmi-exit.c > index b4843f094615..7eff6967530c 100644 > --- a/arch/arm64/kvm/rmi-exit.c > +++ b/arch/arm64/kvm/rmi-exit.c > @@ -116,6 +116,19 @@ static int rec_exit_ripas_change(struct kvm_vcpu *vcpu) > return -EFAULT; > } > > +static int rec_exit_host_call(struct kvm_vcpu *vcpu) > +{ > + int i; > + struct realm_rec *rec = &vcpu->arch.rec; > + > + vcpu->stat.hvc_exit_stat++; > + > + for (i = 0; i < REC_RUN_GPRS; i++) > + vcpu_set_reg(vcpu, i, rec->run->exit.gprs[i]); > + > + return kvm_smccc_call_handler(vcpu); > +} > + > static void update_arch_timer_irq_lines(struct kvm_vcpu *vcpu) > { > struct realm_rec *rec = &vcpu->arch.rec; > @@ -183,6 +196,8 @@ int handle_rec_exit(struct kvm_vcpu *vcpu, int rec_run_ret) > return rec_exit_psci(vcpu); > case RMI_EXIT_RIPAS_CHANGE: > return rec_exit_ripas_change(vcpu); > + case RMI_EXIT_HOST_CALL: > + return rec_exit_host_call(vcpu); > } Probably we should move the RMI_EXIT_HOST_CALL case addition in kvm_rec_pre_enter() to this hunk to keep all in one place ? Otherwise, looks good to me. Suzuki > > kvm_pr_unimpl("Unsupported exit reason: %u\n",