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 7BE432E36E4; Tue, 29 Jul 2025 10:03:13 +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=1753783393; cv=none; b=OLTrq93j6uvoRDtzAmPfPdWuZ5qzuSaZo8ByTiGtu+Hi/Eym02HZWXKAsX/RV5Dn01UByp6NpfSnd/kX+OinzpOOUXatNlRw9r90JHpfdXE3t9uUul5+RYE0kNH1AM0UoL1JztykeNuHhglGqdcT8uS9qACKpGPExFvGfIS0+vg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753783393; c=relaxed/simple; bh=qV5zxLuK9uRH2dermeljaNFBjMCgfl4y632F279d4P8=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=gDiZoYPhFExcNaig8AQaYDc1GC5+ncCp28r46tDE0UaNPKEWXODDINk3DHjsZXJlDp7IKJ2rOdRh2iCPzRs0qr5y+CfIDcNRkRKCOCz/EdvxhKuVtezJvwbf/rqA+acqA5R9DtDSdvQHql01Bgh9sPpBmGF5mi9ig86e6rsRMvs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YLfQvpNE; 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="YLfQvpNE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 098AFC4CEEF; Tue, 29 Jul 2025 10:03:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753783393; bh=qV5zxLuK9uRH2dermeljaNFBjMCgfl4y632F279d4P8=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=YLfQvpNEzpth0fsbyKXumtvW2KfjSGBK433KqBQoTfjvHc5WVo0wI2oMiFFFt7k80 f3euITJUnJ1LVJD1JzGmPLVuEoHiLCBYWmK5K+HSy8N05nD67kefY229xLIj70pc8J V0DUB1XJhTvzWTBXVTIYLTBFBQ834UVbpwiNn0TDUTDaNxrB3Jl9qGV7CwpU4hBqyR 9I4k5gb+VmicBat8HLdo72Jj6YHlEUlNk9eslVAOgxRr/vFzi+PLUgL1W4EH9zzirD O/lsinu13S1qmmRKXNR2rHiT/3t1YoGagsFqVdi+Al8IVYT212oc5vU14FMuVWO+vN XHamfRq5NlX9g== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1ughAs-002HpJ-09; Tue, 29 Jul 2025 11:03:10 +0100 Date: Tue, 29 Jul 2025 11:03:09 +0100 Message-ID: <865xfb8gbm.wl-maz@kernel.org> From: Marc Zyngier To: Andre Przywara Cc: Will Deacon , Julien Thierry , kvm@vger.kernel.org, kvmarm@lists.linux.dev, Alexandru Elisei Subject: Re: [PATCH kvmtool v3 0/6] arm64: Nested virtualization support In-Reply-To: <20250729095745.3148294-1-andre.przywara@arm.com> References: <20250729095745.3148294-1-andre.przywara@arm.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/30.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: andre.przywara@arm.com, will@kernel.org, julien.thierry.kdev@gmail.com, kvm@vger.kernel.org, kvmarm@lists.linux.dev, alexandru.elisei@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Tue, 29 Jul 2025 10:57:39 +0100, Andre Przywara wrote: > > This is v3 of the nested virt support series, adjusting commit messages > and adding a check that FEAT_E2H0 is really available. > ======================================================== > > Thanks to the imperturbable efforts from Marc, arm64 support for nested > virtualization has now reached the mainline kernel, which means the > respective kvmtool support should now be ready as well. > > Patch 1 updates the kernel headers, to get the new EL2 capability, and > the VGIC device control to setup the maintenance IRQ. > Patch 2 introduces the new "--nested" command line option, to let the > VCPUs start in EL2. To allow KVM guests running in such a guest, we also > need VGIC support, which patch 3 allows by setting the maintenance IRQ. > Patch 4 to 6 are picked from Marc's repo, and allow to set the arch > timer offset, enable non-VHE guests (at the cost of losing recursive > nested virtualisation), and also advertise the virtual EL2 timer IRQ. > > Tested on the FVP (with some good deal of patience), and some commercial > (non-fruity) hardware, down to a guest's guest's guest. Thanks for going the extra mile on this, much appreciated. FWIW: Reviewed-by: Marc Zyngier M. -- Without deviation from the norm, progress is not possible.