From patchwork Wed Jul 22 16:22:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 11678915 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A492713A4 for ; Wed, 22 Jul 2020 16:23:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8A1D8206C1 for ; Wed, 22 Jul 2020 16:23:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595434987; bh=JDuAd/IXbI8mLdXTBjc0KnzENivxsT/B90lZcHtXwho=; h=From:To:Cc:Subject:Date:List-ID:From; b=Ym6lWciWgcPFHuPYc5GGsjA1ZMOHNWW2abDHL99bbzR6kzLd1d0lZNwk7fDqyeMGf 0TMmW0Eaqj8UAYtz26zvDT0wYaxBhGpLmBxAytNWE7Gk1bSFFuH7CwVZnlkD59juOC LnCzQH/+W9sl4BU58c2eERY0RgDOU0JrIpnlhv1Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727044AbgGVQXG (ORCPT ); Wed, 22 Jul 2020 12:23:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:46776 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726642AbgGVQXG (ORCPT ); Wed, 22 Jul 2020 12:23:06 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 983052065F; Wed, 22 Jul 2020 16:23:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595434985; bh=JDuAd/IXbI8mLdXTBjc0KnzENivxsT/B90lZcHtXwho=; h=From:To:Cc:Subject:Date:From; b=udcoRBeZF9RGPjhoURMUpD3UOr/OOnpMCD9pTkbd3aDurKJl11MY/yzD6rpZoRjA6 Z/t+wAijL9lSdZLAeCBTU4LBlpf4oj26sPVCr3uXmGNTNIZC46aunqF46m2n5U1Fnb T9gu5YQz2f6mdtoBlP32JjoZHYvc1cawuc1feO5c= Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1jyHWJ-00E1Ih-Uq; Wed, 22 Jul 2020 17:23:04 +0100 From: Marc Zyngier To: kvmarm@lists.cs.columbia.edu Cc: linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, James Morse , Julien Thierry , Suzuki K Poulose , Will Deacon , kernel-team@android.com, Nathan Chancellor , Nick Desaulniers Subject: [PATCH] KVM: arm64: Prevent vcpu_has_ptrauth from generating OOL functions Date: Wed, 22 Jul 2020 17:22:31 +0100 Message-Id: <20200722162231.3689767-1-maz@kernel.org> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, will@kernel.org, kernel-team@android.com, natechancellor@gmail.com, ndesaulniers@google.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org So far, vcpu_has_ptrauth() is implemented in terms of system_supports_*_auth() calls, which are declared "inline". In some specific conditions (clang and SCS), the "inline" very much turns into an "out of line", which leads to a fireworks when this predicate is evaluated on a non-VHE system (right at the beginning of __hyp_handle_ptrauth). Instead, make sure vcpu_has_ptrauth gets expanded inline by directly using the cpus_have_final_cap() helpers, which are __always_inline, generate much better code, and are the only thing that make sense when running at EL2 on a nVHE system. Fixes: 29eb5a3c57f7 ("KVM: arm64: Handle PtrAuth traps early") Reported-by: Nathan Chancellor Reported-by: Nick Desaulniers Signed-off-by: Marc Zyngier Reviewed-by: Nathan Chancellor Tested-by: Nathan Chancellor --- arch/arm64/include/asm/kvm_host.h | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 147064314abf..a8278f6873e6 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -391,9 +391,14 @@ struct kvm_vcpu_arch { #define vcpu_has_sve(vcpu) (system_supports_sve() && \ ((vcpu)->arch.flags & KVM_ARM64_GUEST_HAS_SVE)) -#define vcpu_has_ptrauth(vcpu) ((system_supports_address_auth() || \ - system_supports_generic_auth()) && \ - ((vcpu)->arch.flags & KVM_ARM64_GUEST_HAS_PTRAUTH)) +#ifdef CONFIG_ARM64_PTR_AUTH +#define vcpu_has_ptrauth(vcpu) \ + ((cpus_have_final_cap(ARM64_HAS_ADDRESS_AUTH) || \ + cpus_have_final_cap(ARM64_HAS_GENERIC_AUTH)) && \ + (vcpu)->arch.flags & KVM_ARM64_GUEST_HAS_PTRAUTH) +#else +#define vcpu_has_ptrauth(vcpu) false +#endif #define vcpu_gp_regs(v) (&(v)->arch.ctxt.gp_regs)