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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 43AB2C28CF4 for ; Tue, 16 Nov 2021 01:02:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3B5946326C for ; Tue, 16 Nov 2021 01:02:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376347AbhKPBD5 (ORCPT ); Mon, 15 Nov 2021 20:03:57 -0500 Received: from mail.kernel.org ([198.145.29.99]:44866 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245713AbhKOTVD (ORCPT ); Mon, 15 Nov 2021 14:21:03 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id BE5B96328B; Mon, 15 Nov 2021 18:39:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637001597; bh=fV5uOh05VxwKaWWs9g5a6o9+meRze9rqC/tFkdxlLWA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TVoDhxGGk8231VrLFRL4mTSH8NS7eup5ASeucLBjTJSVjJlOkoohqenAGqJcbbKTR EsBYqeE0PdSdoDB31Gw3iEiaGiUlREhwhYegm7Z1botpHihjrhtHCEIF5rcx6gOY+G ErfsVwDW8jMAot3/YXpdtUKVSgHl3iSpJbAXCx9A= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marc Zyngier , Quentin Perret , Will Deacon , Sasha Levin Subject: [PATCH 5.15 251/917] KVM: arm64: Propagate errors from __pkvm_prot_finalize hypercall Date: Mon, 15 Nov 2021 17:55:46 +0100 Message-Id: <20211115165437.302624318@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165428.722074685@linuxfoundation.org> References: <20211115165428.722074685@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Will Deacon [ Upstream commit 2f2e1a5069679491d18cf9021da19b40c56a17f3 ] If the __pkvm_prot_finalize hypercall returns an error, we WARN but fail to propagate the failure code back to kvm_arch_init(). Pass a pointer to a zero-initialised return variable so that failure to finalise the pKVM protections on a host CPU can be reported back to KVM. Cc: Marc Zyngier Cc: Quentin Perret Signed-off-by: Will Deacon Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20211008135839.1193-5-will@kernel.org Signed-off-by: Sasha Levin --- arch/arm64/kvm/arm.c | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index fe102cd2e5183..9b328bb05596a 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1971,9 +1971,25 @@ out_err: return err; } -static void _kvm_host_prot_finalize(void *discard) +static void _kvm_host_prot_finalize(void *arg) { - WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize)); + int *err = arg; + + if (WARN_ON(kvm_call_hyp_nvhe(__pkvm_prot_finalize))) + WRITE_ONCE(*err, -EINVAL); +} + +static int pkvm_drop_host_privileges(void) +{ + int ret = 0; + + /* + * Flip the static key upfront as that may no longer be possible + * once the host stage 2 is installed. + */ + static_branch_enable(&kvm_protected_mode_initialized); + on_each_cpu(_kvm_host_prot_finalize, &ret, 1); + return ret; } static int finalize_hyp_mode(void) @@ -1987,15 +2003,7 @@ static int finalize_hyp_mode(void) * None of other sections should ever be introspected. */ kmemleak_free_part(__hyp_bss_start, __hyp_bss_end - __hyp_bss_start); - - /* - * Flip the static key upfront as that may no longer be possible - * once the host stage 2 is installed. - */ - static_branch_enable(&kvm_protected_mode_initialized); - on_each_cpu(_kvm_host_prot_finalize, NULL, 1); - - return 0; + return pkvm_drop_host_privileges(); } struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr) -- 2.33.0