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 7AD29C433FE for ; Fri, 8 Oct 2021 13:59:04 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 1BCF9610E5 for ; Fri, 8 Oct 2021 13:59:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 1BCF9610E5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id BB65E4B15D; Fri, 8 Oct 2021 09:59:03 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@kernel.org Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Dvp-5Daf2-+P; Fri, 8 Oct 2021 09:59:01 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 8CA794B166; Fri, 8 Oct 2021 09:59:00 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 342814B0BE for ; Fri, 8 Oct 2021 09:58:59 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id X1MHgGd81LAc for ; Fri, 8 Oct 2021 09:58:58 -0400 (EDT) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 4F1054B154 for ; Fri, 8 Oct 2021 09:58:58 -0400 (EDT) Received: by mail.kernel.org (Postfix) with ESMTPSA id 1166C60FD8; Fri, 8 Oct 2021 13:58:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1633701537; bh=d3wFH/yIetGiq5uriHxlgYqLTUnj/21bzxMY8KFLvuE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gSvmFTxBs3Yv3TsWi3tqX1+3UZfMC5nAidDqLeOMgNhiZwKO3rcX0xDtnTVSqPls8 1WKd7E2cNsrWEuJUcNOegtncGN3biwCWV9+kWuY+DF//z2s+v/+z4t1ZMsq5P5Coey SEG96mqW3SKMHFVwCLFTaWJ7OrBHJqMhfdwIhehq9bA9zvPrcHNM7YbuLTTS4SH9qv uW3OC9bISzBwlAwH5griMOPP3/kdXkWfKVHe8Xga07syTnDPDf9bgxMHUFnzHIDPlU HI1lJZ9b5xg3SDUVuU/nnIT1yCZGYK3XGDbZXXrEyaFTtKBI7T2FJbsxxSWjN4I2MC ZMDtaCgbISNZQ== From: Will Deacon To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 4/6] KVM: arm64: Propagate errors from __pkvm_prot_finalize hypercall Date: Fri, 8 Oct 2021 14:58:37 +0100 Message-Id: <20211008135839.1193-5-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20211008135839.1193-1-will@kernel.org> References: <20211008135839.1193-1-will@kernel.org> MIME-Version: 1.0 Cc: Marc Zyngier , Catalin Marinas , Will Deacon , kvmarm@lists.cs.columbia.edu X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu 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 --- 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 9506cf88fa0e..13bbf35896cd 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1986,9 +1986,25 @@ static int init_hyp_mode(void) 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) @@ -2002,15 +2018,7 @@ 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) -- 2.33.0.882.g93a45727a2-goog _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm