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| author | Marc Zyngier | 2014-02-19 10:33:14 +0100 |
|---|---|---|
| committer | Marc Zyngier | 2016-02-29 19:34:18 +0100 |
| commit | 1f364c8c48a0767885a18451ee074c64b454157a (patch) | |
| tree | 3fa0d98862ed916c5b2767c6015fa563d89c2857 /arch/arm64/Kconfig | |
| parent | arm64: hw_breakpoint: Allow EL2 breakpoints if running in HYP (diff) | |
| download | kernel-qcow2-linux-1f364c8c48a0767885a18451ee074c64b454157a.tar.gz kernel-qcow2-linux-1f364c8c48a0767885a18451ee074c64b454157a.tar.xz kernel-qcow2-linux-1f364c8c48a0767885a18451ee074c64b454157a.zip | |
arm64: VHE: Add support for running Linux in EL2 mode
With ARMv8.1 VHE, the architecture is able to (almost) transparently
run the kernel at EL2, despite being written for EL1.
This patch takes care of the "almost" part, mostly preventing the kernel
from dropping from EL2 to EL1, and setting up the HYP configuration.
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'arch/arm64/Kconfig')
| -rw-r--r-- | arch/arm64/Kconfig | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 8cc62289a63e..cf118d93290d 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -750,6 +750,19 @@ config ARM64_LSE_ATOMICS not support these instructions and requires the kernel to be built with binutils >= 2.25. +config ARM64_VHE + bool "Enable support for Virtualization Host Extensions (VHE)" + default y + help + Virtualization Host Extensions (VHE) allow the kernel to run + directly at EL2 (instead of EL1) on processors that support + it. This leads to better performance for KVM, as they reduce + the cost of the world switch. + + Selecting this option allows the VHE feature to be detected + at runtime, and does not affect processors that do not + implement this feature. + endmenu endmenu |