From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 BCA3F3DB328; Thu, 17 Sep 2026 07:57:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789631822; cv=none; b=uuN9S3PolKmFOgax2lliqODFYMYj3eklFOrpDMtmbXfsIoy2TbYHkvXcYfY7JrMO3bryP1n9lmlckNlF0Qtx86TPM2lkkkT3SyLlSlJniRii9VGcMuzcweltxebmxc4Tlcm+brCJgwusKCsE4eHtEoL69CkHe1R0v410Sym1w6Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789631822; c=relaxed/simple; bh=flwm51PTddp8bOXmpbcTF9d5R+dkajh8ncYWbuDyxRk=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=Wl1EVw+WD8NBRXgSrnX3nFrWT7BxdQmjfKAW7cAtSdlvEz5LoQXWu5QEA+rwa+qLMcF0y+5PzR3DhMwNv6lJLHMEPEsifmdMhNcQsVmUT/Sx0RvkGLBP+tfy0RxVGk9vdnzi7FaSnojOFJvlWp6Bw7jQy1isRT+f9b3JY/xzjh4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Fyv8H5Zd; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Fyv8H5Zd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CED881F000FF; Thu, 17 Sep 2026 07:56:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789631819; bh=c5nHfb0sN8awpqWQUUf2qpdir+xWpEhP8GLUQyh2snk=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=Fyv8H5ZdWDAqKNy6lCNwJD0GdWelLq+Vv2VWJUXPR6sk2T8RpIum4o7exvCiYCrXa K2bv4rHCB1g95P02+cxUnWktKD2D1RXLBoN5uBDgzStA/jYBMb61thlz9XfCFcBmjf JVWL2KsLc11C3KUc7hdz6pBoGJXxSjIKmccgxEwAE1+c7P3Ltvnwuqs/YQvfrdk31s +BmuVlwfoA1IuTTOsPprMrg/m1s1tAxP/Pgi5jn6EOolMiHLGAFls9ppYoEQm842QI VJNzx47uYGIXfwegd9vqV2QnK0geFPdfYDKOFBxz0cCAxg+DNZkvH4UjCbPhuPB4zC /5hZvKqt5DfCg== 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 4.98.2) (envelope-from ) id 1x76zJ-00000009yQd-1QJv; Thu, 17 Sep 2026 07:56:57 +0000 Date: Thu, 17 Sep 2026 08:56:56 +0100 Message-ID: <867bkk5n07.wl-maz@kernel.org> From: Marc Zyngier To: Itaru Kitayama Cc: Wei-Lin Chang , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, Oliver Upton , Fuad Tabba , Joey Gouly , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , Mark Rutland , Wang Han , Shuai Xue , "Lorenzo Stoakes (ARM)" Subject: Re: [PATCH v6 0/7] KVM: arm64: nv: Implement nested stage-2 reverse map In-Reply-To: References: <20260915154305.3852871-1-weilin.chang@arm.com> <86ld9165cr.wl-maz@kernel.org> 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: linux-kernel@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: itaru.kitayama@fujitsu.com, weilin.chang@arm.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, oupton@kernel.org, fuad.tabba@linux.dev, joey.gouly@arm.com, seiden@linux.ibm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, mark.rutland@arm.com, wanghan@linux.alibaba.com, xueshuai@linux.alibaba.com, ljs@kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Thu, 17 Sep 2026 07:51:19 +0100, Itaru Kitayama wrote: > > On Wed, Sep 16, 2026 at 08:08:20AM +0100, Marc Zyngier wrote: > > On Wed, 16 Sep 2026 00:27:22 +0100, > > Itaru Kitayama wrote: > > > > > > On Wed, Sep 16, 2026 at 12:22:30AM +0100, Wei-Lin Chang wrote: > > > > On Wed, Sep 16, 2026 at 06:49:57AM +0900, Itaru Kitayama wrote: > > > > > On Tue, Sep 15, 2026 at 04:42:58PM +0100, Wei-Lin Chang wrote: > > > > > > Hi, > > > > > > > > > > > > This is v6 of optimizing the shadow s2 mmu unmapping during MMU > > > > > > notifiers. > > > > > > > > > > > > This version fixes a few issues, and adds Marc's space optimization > > > > > > for kvm_guest_s2_mapping [1]. Please see the changelog for the details. > > > > > > > > > > > > Tested by booting L3, and running in-kernel targetted tests described > > > > > > in [2]. v5 got some tested-by's from Itaru and Wang (thanks), I didn't > > > > > > carry them over since some bugs fixed in v6 are non-obvious. Some > > > > > > retest would be much appreciated! > > > > > > > > > > How did you boot into L3, with KVM selftest or recrusively boot on HW? > > > > > > > > I just recrusively booted VMs on hardware. :) > > > > > > Good. Then I actually tried that on Grace CPUs, but letting L1 boot > > > with nested mode did not print "VHE+NV2" KVM init log in dmesg, thus not > > > able to boot L3. Do I need to add other than kvm.arm-mode=nested to command line? > > > > kvm-arm.mode=nested, as documented. That also puts in perspective your > > TB tag on the whole series... > > Yes. Using kvmtool's --nested option did not bring vCPU with the VHE+NV2 boot > log. The Host kernel is Wei-Lin's version 6 booted on Grace CPUs, and > the guest kernel is today's kvmarm/fixes plus Wei-Lin's shadow stage 2 ptdump fix. What have you tested exactly? If you're not able to boot a working L1 guest as a NV2 hypervisor, you're probably doing something wrong. M. -- Without deviation from the norm, progress is not possible.