arm64: Enable CONFIG_ARM64_SW_TTBR0_PAN
authorCatalin Marinas <catalin.marinas@arm.com>
Fri, 1 Jul 2016 17:25:31 +0000 (18:25 +0100)
committerCatalin Marinas <catalin.marinas@arm.com>
Mon, 21 Nov 2016 18:48:55 +0000 (18:48 +0000)
commitba42822af1c287f038aa550f3578c61c212a892e
tree7697e71a152e5294568b1a43695adcfeac08f166
parent9cf09d68b89ae5fe0261dcc69464bcc676900af6
arm64: Enable CONFIG_ARM64_SW_TTBR0_PAN

This patch adds the Kconfig option to enable support for TTBR0 PAN
emulation. The option is default off because of a slight performance hit
when enabled, caused by the additional TTBR0_EL1 switching during user
access operations or exception entry/exit code.

Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arch/arm64/Kconfig