--- /dev/null
+From 7915f13326a995a2a91d52fae13794357cb8e1d3 Mon Sep 17 00:00:00 2001
+From: Mark Rutland <mark.rutland@arm.com>
+Date: Fri, 18 Jan 2019 17:55:54 +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 4.4.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 013b7de45ee7..d7e7cf56e8d6 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_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
+
--- /dev/null
+From 358c9d5eac5ca38ff4f1ca49fd102f629d2c660b Mon Sep 17 00:00:00 2001
+From: Mark Rutland <mark.rutland@arm.com>
+Date: Fri, 18 Jan 2019 17:55:53 +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 4.4.y: non-VHE only; __deactivate_traps_nvhe in
+ assembly; add #include]
+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 | 3 ++-
+ arch/arm64/kvm/hyp.S | 2 +-
+ 3 files changed, 4 insertions(+), 2 deletions(-)
+
+diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
+index ef8e13d379cb..013b7de45ee7 100644
+--- a/arch/arm64/include/asm/kvm_arm.h
++++ b/arch/arm64/include/asm/kvm_arm.h
+@@ -81,6 +81,7 @@
+ 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)
+
+
+ /* Hyp System Control Register (SCTLR_EL2) bits */
+diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
+index d019c3a58cc2..0382eba4bf7b 100644
+--- a/arch/arm64/kernel/head.S
++++ b/arch/arm64/kernel/head.S
+@@ -30,6 +30,7 @@
+ #include <asm/cache.h>
+ #include <asm/cputype.h>
+ #include <asm/kernel-pgtable.h>
++#include <asm/kvm_arm.h>
+ #include <asm/memory.h>
+ #include <asm/pgtable-hwdef.h>
+ #include <asm/pgtable.h>
+@@ -464,7 +465,7 @@ CPU_LE( bic x0, x0, #(3 << 24) ) // Clear the EE and E0E bits for EL1
+ ret
+
+ /* Hyp configuration. */
+-2: mov x0, #(1 << 31) // 64-bit EL1
++2: mov_q x0, HCR_HOST_NVHE_FLAGS
+ msr hcr_el2, x0
+
+ /* Generic timers. */
+diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S
+index 86c289832272..8d3da858c257 100644
+--- a/arch/arm64/kvm/hyp.S
++++ b/arch/arm64/kvm/hyp.S
+@@ -494,7 +494,7 @@
+ .endm
+
+ .macro deactivate_traps
+- mov x2, #HCR_RW
++ mov_q x2, HCR_HOST_NVHE_FLAGS
+ msr hcr_el2, x2
+ msr hstr_el2, xzr
+
+--
+2.19.1
+
projects / thirdparty / kernel / stable-queue.git / commitdiff
