[PATCH 2/2] arm/arm64: kvm: Disable branch profiling in HYP code

[Marc Zyngier]

On 19/10/17 16:45, Julien Thierry wrote:
> When HYP code runs into branch profiling code, it attempts to jump to
> unmapped memory, causing a HYP Panic.
> 
> Disable the branch profiling for code designed to run at HYP mode.
> 
> Signed-off-by: Julien Thierry <julien.thierry at arm.com>
> Cc: Marc Zyngier <marc.zyngier at arm.com>
> Cc: Christoffer Dall <christoffer.dall at linaro.org>
> Cc: Catalin Marinas <catalin.marinas at arm.com>
> Cc: Will Deacon <will.deacon at arm.com>
> Cc: Russell King <linux at armlinux.org.uk>
> Cc: <stable at vger.kernel.org>
> ---
>  arch/arm/kvm/hyp/Makefile   | 2 +-
>  arch/arm64/kvm/hyp/Makefile | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/kvm/hyp/Makefile b/arch/arm/kvm/hyp/Makefile
> index 8679405..92eab1d 100644
> --- a/arch/arm/kvm/hyp/Makefile
> +++ b/arch/arm/kvm/hyp/Makefile
> @@ -2,7 +2,7 @@
>  # Makefile for Kernel-based Virtual Machine module, HYP part
>  #
> 
> -ccflags-y += -fno-stack-protector
> +ccflags-y += -fno-stack-protector -DDISABLE_BRANCH_PROFILING
> 
>  KVM=../../../../virt/kvm
> 
> diff --git a/arch/arm64/kvm/hyp/Makefile b/arch/arm64/kvm/hyp/Makefile
> index 14c4e3b..48b0354 100644
> --- a/arch/arm64/kvm/hyp/Makefile
> +++ b/arch/arm64/kvm/hyp/Makefile
> @@ -2,7 +2,7 @@
>  # Makefile for Kernel-based Virtual Machine module, HYP part
>  #
> 
> -ccflags-y += -fno-stack-protector
> +ccflags-y += -fno-stack-protector -DDISABLE_BRANCH_PROFILING
> 
>  KVM=../../../../virt/kvm
> 
> --
> 1.9.1
> 

Nice catch.

Acked-by: Marc Zyngier <marc.zyngier at arm.com>

	M.
-- 
Jazz is not dead. It just smells funny...