evie/android_kernel_oneplus_msm8998
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

arm64: Don't trap host pointer auth use to EL2

Browse source 
[ 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>
This commit is contained in:
Mark Rutland 2019-01-18 17:55:54 +00:00 • committed by Greg Kroah-Hartman
parent 0b6c2279b7
commit 5b1d8e5d86
1 changed files with 3 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
arch/arm64/include/asm/kvm_arm.h
View file

@ -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 */