--- /dev/null
+From 2f37643c6172961d0e855cc2e77791a88c0116b6 Mon Sep 17 00:00:00 2001
+From: Mark Rutland <mark.rutland@arm.com>
+Date: Fri, 18 Jan 2019 17:56:27 +0000
+Subject: arm64: Don't trap host pointer auth use to EL2
+
+[ 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 <richard.henderson@linaro.org>
+Signed-off-by: Mark Rutland <mark.rutland@arm.com>
+Acked-by: Christoffer Dall <christoffer.dall@arm.com>
+Cc: Catalin Marinas <catalin.marinas@arm.com>
+Cc: Marc Zyngier <marc.zyngier@arm.com>
+Cc: Will Deacon <will.deacon@arm.com>
+Cc: kvmarm@lists.cs.columbia.edu
+Signed-off-by: Will Deacon <will.deacon@arm.com>
+[kristina: backport to 4.9.y: adjust context]
+Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
+Signed-off-by: Sasha Levin <sashal@kernel.org>
+---
+ 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 352bf2f7f60a..a11c8c2915c9 100644
+--- a/arch/arm64/include/asm/kvm_arm.h
++++ b/arch/arm64/include/asm/kvm_arm.h
+@@ -23,6 +23,8 @@
+ #include <asm/types.h>
+
+ /* Hyp Configuration Register (HCR) bits */
++#define HCR_API (UL(1) << 41)
++#define HCR_APK (UL(1) << 40)
+ #define HCR_E2H (UL(1) << 34)
+ #define HCR_ID (UL(1) << 33)
+ #define HCR_CD (UL(1) << 32)
+@@ -82,7 +84,7 @@
+ HCR_AMO | HCR_SWIO | HCR_TIDCP | HCR_RW)
+ #define HCR_VIRT_EXCP_MASK (HCR_VSE | 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)
+ #define HCR_HOST_VHE_FLAGS (HCR_RW | HCR_TGE | HCR_E2H)
+
+ /* TCR_EL2 Registers bits */
+--
+2.19.1
+
--- /dev/null
+From d04753699d47c264c12ddfd96e4285e82b8b047b Mon Sep 17 00:00:00 2001
+From: Mark Rutland <mark.rutland@arm.com>
+Date: Fri, 18 Jan 2019 17:56:26 +0000
+Subject: arm64/kvm: consistently handle host HCR_EL2 flags
+
+[ Backport of upstream commit 4eaed6aa2c628101246bcabc91b203bfac1193f8 ]
+
+In KVM we define the configuration of HCR_EL2 for a VHE HOST in
+HCR_HOST_VHE_FLAGS, but we don't have a similar definition for the
+non-VHE host flags, and open-code HCR_RW. Further, in head.S we
+open-code the flags for VHE and non-VHE configurations.
+
+In future, we're going to want to configure more flags for the host, so
+lets add a HCR_HOST_NVHE_FLAGS defintion, and consistently use both
+HCR_HOST_VHE_FLAGS and HCR_HOST_NVHE_FLAGS in the kvm code and head.S.
+
+We now use mov_q to generate the HCR_EL2 value, as we use when
+configuring other registers in head.S.
+
+Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
+Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
+Signed-off-by: Mark Rutland <mark.rutland@arm.com>
+Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
+Cc: Catalin Marinas <catalin.marinas@arm.com>
+Cc: Marc Zyngier <marc.zyngier@arm.com>
+Cc: Will Deacon <will.deacon@arm.com>
+Cc: kvmarm@lists.cs.columbia.edu
+Signed-off-by: Will Deacon <will.deacon@arm.com>
+[kristina: backport to 4.9.y: adjust context]
+Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
+Signed-off-by: Sasha Levin <sashal@kernel.org>
+---
+ arch/arm64/include/asm/kvm_arm.h | 1 +
+ arch/arm64/kernel/head.S | 5 ++---
+ arch/arm64/kvm/hyp/switch.c | 2 +-
+ 3 files changed, 4 insertions(+), 4 deletions(-)
+
+diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
+index 68dedca5a47e..352bf2f7f60a 100644
+--- a/arch/arm64/include/asm/kvm_arm.h
++++ b/arch/arm64/include/asm/kvm_arm.h
+@@ -82,6 +82,7 @@
+ HCR_AMO | HCR_SWIO | HCR_TIDCP | HCR_RW)
+ #define HCR_VIRT_EXCP_MASK (HCR_VSE | HCR_VI | HCR_VF)
+ #define HCR_INT_OVERRIDE (HCR_FMO | HCR_IMO)
++#define HCR_HOST_NVHE_FLAGS (HCR_RW)
+ #define HCR_HOST_VHE_FLAGS (HCR_RW | HCR_TGE | HCR_E2H)
+
+ /* TCR_EL2 Registers bits */
+diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
+index fa52817d84c5..3289d1458791 100644
+--- a/arch/arm64/kernel/head.S
++++ b/arch/arm64/kernel/head.S
+@@ -517,10 +517,9 @@ CPU_LE( bic x0, x0, #(3 << 24) ) // Clear the EE and E0E bits for EL1
+ #endif
+
+ /* Hyp configuration. */
+- mov x0, #HCR_RW // 64-bit EL1
++ mov_q x0, HCR_HOST_NVHE_FLAGS
+ cbz x2, set_hcr
+- orr x0, x0, #HCR_TGE // Enable Host Extensions
+- orr x0, x0, #HCR_E2H
++ mov_q x0, HCR_HOST_VHE_FLAGS
+ set_hcr:
+ msr hcr_el2, x0
+ isb
+diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
+index 12f9d1ecdf4c..115b0955715f 100644
+--- a/arch/arm64/kvm/hyp/switch.c
++++ b/arch/arm64/kvm/hyp/switch.c
+@@ -112,7 +112,7 @@ static void __hyp_text __deactivate_traps_vhe(void)
+
+ static void __hyp_text __deactivate_traps_nvhe(void)
+ {
+- write_sysreg(HCR_RW, hcr_el2);
++ write_sysreg(HCR_HOST_NVHE_FLAGS, hcr_el2);
+ write_sysreg(CPTR_EL2_DEFAULT, cptr_el2);
+ }
+
+--
+2.19.1
+
projects / thirdparty / kernel / stable-queue.git / commitdiff
