[PATCH V2] arm64: KVM: Fix HCR_EL2 and VTCR_EL2 configuration bits

Christopher Covington cov at codeaurora.org
Mon May 13 11:23:05 EDT 2013


Hi Pranavkumar,

On 05/10/2013 03:23 AM, Pranavkumar Sawargaonkar wrote:
> This patch does following fixes:
> 
> 1. Make HCR_* flags as unsigned long long constants
> Reason : By default, compiler assumes numeric constants as
> signed hence sign extending it when assigned to unsigned variable
> such as hcr_el2 (in VCPU context). This accidently sets HCR_ID and
> HCR_CD making entire guest memory non-cacheable. On real HW, this
> breaks Stage2 ttbl walks and also breaks VirtIO.
> 
> 2. VTCR_EL2_ORGN0_WBWA and VTCR_EL2_IRGN0_WBWA macros.
> 
> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar at linaro.org>
> Signed-off-by: Anup Patel <anup.patel at linaro.org>
> ---
>  arch/arm64/include/asm/kvm_arm.h |   73 +++++++++++++++++++-------------------
>  1 file changed, 37 insertions(+), 36 deletions(-)
> 
> diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
> index 8ced0ca..14ead69 100644
> --- a/arch/arm64/include/asm/kvm_arm.h
> +++ b/arch/arm64/include/asm/kvm_arm.h
> @@ -18,44 +18,45 @@
>  #ifndef __ARM64_KVM_ARM_H__
>  #define __ARM64_KVM_ARM_H__
>  
> +#include <linux/const.h>
>  #include <asm/types.h>
>  
>  /* Hyp Configuration Register (HCR) bits */
> -#define HCR_ID		(1 << 33)
> -#define HCR_CD		(1 << 32)
> +#define HCR_ID		(UL(0x1) << 33)
> +#define HCR_CD		(UL(0x1) << 32)

Consider using the BIT() macro from linux/bitops.h to improve readability.

[...]

Christopher

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