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 X-Spam-Level: X-Spam-Status: No, score=-23.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D570CC433E0 for ; Mon, 18 Jan 2021 13:33:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 98F94222F9 for ; Mon, 18 Jan 2021 13:33:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392199AbhARNdB (ORCPT ); Mon, 18 Jan 2021 08:33:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41038 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392208AbhARNaS (ORCPT ); Mon, 18 Jan 2021 08:30:18 -0500 Received: from mail-wm1-x32d.google.com (mail-wm1-x32d.google.com [IPv6:2a00:1450:4864:20::32d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55258C061574 for ; Mon, 18 Jan 2021 05:29:38 -0800 (PST) Received: by mail-wm1-x32d.google.com with SMTP id y187so13798931wmd.3 for ; Mon, 18 Jan 2021 05:29:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=azSUNypoUfXkpBNPZlINL/zcgEf9pXSAwHyqYLVciok=; b=Hdiq7ktUglPw2zVeBs7zzB+XtzIcpfitaPaWUCwOh9Lp9grsNlqjNfLEhWzbdqjyLr XwhO7yBQNhaa8PVRuXmwzBb4HoBM0FMU2kRFd1BKaZ4uX5qIute8XLIkw7aleByJtYGf BXUpgbwE6/LwYO5XnDY7K5pT8zQ7ng+PiUgi2+ewvj/+yl6NJJxZ448sKc8AC8xmExWX iyq8MLnxO818KbMz6m0jlISbSB5HOIgfxzwLAjOrQi8IDKamWFVMBQUCoTXjfam8WtZw NpPZUO8H3m3DlxZyqJQvFXYlVIjWbYG5/v1nBe7gt5DE1oDYURdCVacMi3U98mL76gyk ElPA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=azSUNypoUfXkpBNPZlINL/zcgEf9pXSAwHyqYLVciok=; b=UkUFnO8ggEXJjiemY4t9wK+24VdMFmAVeiRzpb+zM2mVrianaFqhk77SUyVQzgdT1O tEQEcGb6Wa7y7RggMMwf1SJ19h4+wgUISp4vzZ3lv85Mrtm5q40Itl/M+fZzOk5bWV6d 1f3b/pXcvEF5oRgvJvmprKEiXFgknRZAPhlZ3kLUppBEeLEHk1EtDzN1bLUXIE/jCwxm yayrjD1TXIrN8CZETBF9pWyrrQoEPtp59u5cGZ7gycD672lYgp1CzuZfPvBHHFZgID5e 3qnbSHSa9BkVD1Ry1UI2D3jufquqt47VQP6G4NDzdQhezfkXLrwUlP8lbJCcceJSmMFx UkSQ== X-Gm-Message-State: AOAM532md6AtJNYvdafz6mDO2FpBqV9vv+miJ6NP5OvbG5LrgglMnVWv WFOPnMiCVtxM+7tyjhXQ1WdxLiruRJBg3w== X-Google-Smtp-Source: ABdhPJwuICFtdmLsGWmzfsOVlfdR9kik5BbE6wWl9u1IG/qQD53UckSQXbc/RrHmiYn+JKe9B1+ugg== X-Received: by 2002:a1c:40d6:: with SMTP id n205mr21244747wma.0.1610976576985; Mon, 18 Jan 2021 05:29:36 -0800 (PST) Received: from google.com ([2a01:4b00:8523:2d03:3d4d:985d:87b7:4d55]) by smtp.gmail.com with ESMTPSA id g5sm30955277wro.60.2021.01.18.05.29.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 18 Jan 2021 05:29:36 -0800 (PST) Date: Mon, 18 Jan 2021 13:29:35 +0000 From: David Brazdil To: Marc Zyngier Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, Catalin Marinas , Will Deacon , Mark Rutland , Alexandru Elisei , Ard Biesheuvel , Jing Zhang , Ajay Patil , Prasad Sodagudi , Srinivas Ramana , James Morse , Julien Thierry , Suzuki K Poulose , kernel-team@android.com Subject: Re: [PATCH v4 17/21] KVM: arm64: Document HVC_VHE_RESTART stub hypercall Message-ID: <20210118132935.mutemf7j7wtyz7wz@google.com> References: <20210118094533.2874082-1-maz@kernel.org> <20210118094533.2874082-18-maz@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210118094533.2874082-18-maz@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 18, 2021 at 09:45:29AM +0000, Marc Zyngier wrote: > For completeness, let's document the HVC_VHE_RESTART stub. > > Signed-off-by: Marc Zyngier Acked-by: David Brazdil > --- > Documentation/virt/kvm/arm/hyp-abi.rst | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/Documentation/virt/kvm/arm/hyp-abi.rst b/Documentation/virt/kvm/arm/hyp-abi.rst > index 83cadd8186fa..1ba628baf11b 100644 > --- a/Documentation/virt/kvm/arm/hyp-abi.rst > +++ b/Documentation/virt/kvm/arm/hyp-abi.rst > @@ -58,6 +58,15 @@ these functions (see arch/arm{,64}/include/asm/virt.h): > into place (arm64 only), and jump to the restart address while at HYP/EL2. > This hypercall is not expected to return to its caller. > > +* :: > + > + x0 = HVC_VHE_RESTART (arm64 only) > + > + Attempt to upgrade the kernel's exception level from EL1 to EL2 by enabling > + the VHE mode. This is conditioned by the CPU supporting VHE, the EL2 MMU > + being off, and VHE not being disabled by any other mean (comment line option, 'means' (both singular and plural), and 'command line' > + for example). > + > Any other value of r0/x0 triggers a hypervisor-specific handling, > which is not documented here. > > -- > 2.29.2 >