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 802622AD1B; Tue, 29 Sep 2026 19:32:56 +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=1790710378; cv=none; b=d9T3iPoopX/PAMpDA1eK7zTPDG1Tl9nQOTH974/iodwYQXSOeJQ6mYvjvQn9UDbGyymf6p/X5rmhY74T93KaoCEvWi/rLl5lksdVuEYuj3jl5tO6mGChWL/1cnboKFPuYsRwftFkZhVmVZ2b9nzFNdBnNKclzbN655q/lNTezWo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790710378; c=relaxed/simple; bh=sX27KGQtyN62UHaTnPRgJtDI+PC+O7kGFSzjRgNzjCU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=hINjzUI3NOQ1UO5t5NH7RDK3Gd1noy95asAQ0+DPStCOKBoEsac3uUHWJXEHsZOxZ+toFWrorFFSplBIDdE7QBwn4ePGLs3Yq245AhbM9hs96RXk16CNNNJd4Y2wJ9cEIK2D3azzpTeR05av2jfiL1ktim2Crp/eFjuGkPIoeyA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PGqNQ2Ro; 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="PGqNQ2Ro" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 329571F00893; Tue, 29 Sep 2026 19:32:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790710376; bh=/OfoBrmWG0bD9vaJRjd0S5rVgXGLpoNdNRXURAF0ZLk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=PGqNQ2Ro+s162Kh1Rn4dC0vD9IhjQndkykHb5cglE2KR7qfti31OdfG9NSJIJ+WOY 5A3XRybO06J9BlMwuKzbXzEYXA43hz8Qx/tFVP+ADadyGBUDuT95mJyVCbxFVZAag2 uTMmN+lJO9NTV9z6tw0Cz/kxylAyi2+Z03tIC8PGRmumdSmIlWY6cK2Dc9bGYJ0mQA KZEQAMSYM284fLzndQHYGWhYFE9ypJMYX72EctmMcHXeolykzuwHhky0D+TKTONzda WPOkZPxjyu6nSSnOCsdVba7Magggv08NfiZXZNDj/mpjquXh8U7GyIrxWM1DCg62oP QnGKSgp5cnwCw== From: Oliver Upton To: Marc Zyngier , kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Fuad Tabba Cc: Oliver Upton , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Steffen Eiden , Catalin Marinas , Will Deacon , Mark Rutland , Quentin Perret , Vincent Donnefort , Wei-Lin Chang , Venkata Rao Kakani , linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 0/4] KVM: arm64: Fix HCR_EL2 for non-protected VMs in pKVM Date: Tue, 29 Sep 2026 12:32:52 -0700 Message-ID: <179071036893.5634.18190465958377898679.b4-ty@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260929090031.3829185-1-fuad.tabba@linux.dev> References: <20260929090031.3829185-1-fuad.tabba@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit On Tue, 29 Sep 2026 10:00:27 +0100, Fuad Tabba wrote: > Changes since v2 [1]: > - Patch 1: apply the FGUs on a CPU without FEAT_FGT instead of moving > the check in handle_tlbi_el1() (Oliver [2]). Wei-Lin's Reviewed-by > dropped with the rewrite. > > In pKVM, EL2 sets a non-protected VM's HCR_EL2 in pkvm_vcpu_reset_hcr(), > which misses the RW, TID5 and TTLBOS handling of vcpu_set_hcr(), and > takes only TWI, TWE and VSE from the host. As a result, an AArch32 VM > can't run, a VM can read GMID_EL1 or execute a TLBI OS its ID registers > hide, and the host's TVM, VI and VF never reach it. > > [...] Applied to fixes, thanks! [1/4] KVM: arm64: Apply the fine-grained UNDEFs without FEAT_FGT https://git.kernel.org/kvmarm/kvmarm/c/4bdd2b3a708c [2/4] KVM: arm64: Clear HCR_EL2.RW for 32-bit non-protected vCPUs https://git.kernel.org/kvmarm/kvmarm/c/80ae56184b57 [3/4] KVM: arm64: Use the host's HCR_EL2 for non-protected VMs in pKVM https://git.kernel.org/kvmarm/kvmarm/c/04447b95c62b [4/4] KVM: arm64: selftests: Check a feature hidden in an ID register is UNDEF https://git.kernel.org/kvmarm/kvmarm/c/afb4334fb52c -- Best, Oliver