From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751326AbeECNWL (ORCPT ); Thu, 3 May 2018 09:22:11 -0400 Received: from foss.arm.com ([217.140.101.70]:41608 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751412AbeECNUu (ORCPT ); Thu, 3 May 2018 09:20:50 -0400 From: Mark Rutland To: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, kvmarm@lists.cs.columbia.edu, catalin.marinas@arm.com, christoffer.dall@arm.com, drjones@redhat.com, marc.zyngier@arm.com, mark.rutland@arm.com, ramana.radhakrishnan@arm.com, suzuki.poulose@arm.com, will.deacon@arm.com, awallis@codeaurora.org Subject: [PATCHv4 04/10] arm64: Don't trap host pointer auth use to EL2 Date: Thu, 3 May 2018 14:20:25 +0100 Message-Id: <20180503132031.25705-5-mark.rutland@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20180503132031.25705-1-mark.rutland@arm.com> References: <20180503132031.25705-1-mark.rutland@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org To allow EL0 (and/or EL1) to use pointer authentication functionality, we must ensure that pointer authentication instructions and accesses to pointer authentication keys are not trapped to EL2. This patch ensures that HCR_EL2 is configured appropriately when the kernel is booted at EL2. For non-VHE kernels we set HCR_EL2.{API,APK}, ensuring that EL1 can access keys and permit EL0 use of instructions. For VHE kernels host EL0 (TGE && E2H) is unaffected by these settings, and it doesn't matter how we configure HCR_EL2.{API,APK}, so we don't bother setting them. This does not enable support for KVM guests, since KVM manages HCR_EL2 itself when running VMs. Signed-off-by: Mark Rutland Acked-by: Christoffer Dall Cc: Catalin Marinas Cc: Marc Zyngier Cc: Will Deacon Cc: kvmarm@lists.cs.columbia.edu --- arch/arm64/include/asm/kvm_arm.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index 89b3dda7e3cb..4d57e1e58323 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -23,6 +23,8 @@ #include /* Hyp Configuration Register (HCR) bits */ +#define HCR_API (UL(1) << 41) +#define HCR_APK (UL(1) << 40) #define HCR_TEA (UL(1) << 37) #define HCR_TERR (UL(1) << 36) #define HCR_TLOR (UL(1) << 35) @@ -86,7 +88,7 @@ HCR_AMO | HCR_SWIO | HCR_TIDCP | HCR_RW | HCR_TLOR | \ HCR_FMO | HCR_IMO) #define HCR_VIRT_EXCP_MASK (HCR_VSE | HCR_VI | HCR_VF) -#define HCR_HOST_NVHE_FLAGS (HCR_RW) +#define HCR_HOST_NVHE_FLAGS (HCR_RW | HCR_API | HCR_APK) #define HCR_HOST_VHE_FLAGS (HCR_RW | HCR_TGE | HCR_E2H) /* TCR_EL2 Registers bits */ -- 2.11.0