From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Kroah-Hartman Subject: [PATCH 4.4 041/104] arm64: Dont trap host pointer auth use to EL2 Date: Thu, 24 Jan 2019 20:19:30 +0100 Message-ID: <20190124190159.891049721@linuxfoundation.org> References: <20190124190154.968308875@linuxfoundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190124190154.968308875@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Richard Henderson , Mark Rutland , Christoffer Dall , Catalin Marinas , Marc Zyngier , Will Deacon , kvmarm@lists.cs.columbia.edu, Kristina Martsenko , Sasha Levin List-Id: kvmarm@lists.cs.columbia.edu 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ [ Backport of upstream commit b3669b1e1c09890d61109a1a8ece2c5b66804714 ] 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. Reviewed-by: Richard Henderson Signed-off-by: Mark Rutland Acked-by: Christoffer Dall Cc: Catalin Marinas Cc: Marc Zyngier Cc: Will Deacon Cc: kvmarm@lists.cs.columbia.edu Signed-off-by: Will Deacon [kristina: backport to 4.4.y: adjust context] Signed-off-by: Kristina Martsenko Signed-off-by: Sasha Levin --- 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 013b7de45ee7..d7e7cf56e8d6 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_ID (UL(1) << 33) #define HCR_CD (UL(1) << 32) #define HCR_RW_SHIFT 31 @@ -81,7 +83,7 @@ HCR_AMO | HCR_SWIO | HCR_TIDCP | HCR_RW) #define HCR_VIRT_EXCP_MASK (HCR_VA | HCR_VI | HCR_VF) #define HCR_INT_OVERRIDE (HCR_FMO | HCR_IMO) -#define HCR_HOST_NVHE_FLAGS (HCR_RW) +#define HCR_HOST_NVHE_FLAGS (HCR_RW | HCR_API | HCR_APK) /* Hyp System Control Register (SCTLR_EL2) bits */ -- 2.19.1