From: Marc Zyngier maz@kernel.org
commit 3204be4109ad681523e3461ce64454c79278450a upstream.
AArch32 CP1x registers are overlayed on their AArch64 counterparts in the vcpu struct. This leads to an interesting problem as they are stored in their CPU-local format, and thus a CP1x register doesn't "hit" the lower 32bit portion of the AArch64 register on a BE host.
To workaround this unfortunate situation, introduce a bias trick in the vcpu_cp1x() accessors which picks the correct half of the 64bit register.
Cc: stable@vger.kernel.org Reported-by: James Morse james.morse@arm.com Tested-by: James Morse james.morse@arm.com Acked-by: James Morse james.morse@arm.com Signed-off-by: Marc Zyngier maz@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/arm64/include/asm/kvm_host.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -178,8 +178,10 @@ struct kvm_vcpu_arch { * CP14 and CP15 live in the same array, as they are backed by the * same system registers. */ -#define vcpu_cp14(v,r) ((v)->arch.ctxt.copro[(r)]) -#define vcpu_cp15(v,r) ((v)->arch.ctxt.copro[(r)]) +#define CPx_BIAS IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) + +#define vcpu_cp14(v,r) ((v)->arch.ctxt.copro[(r) ^ CPx_BIAS]) +#define vcpu_cp15(v,r) ((v)->arch.ctxt.copro[(r) ^ CPx_BIAS])
#ifdef CONFIG_CPU_BIG_ENDIAN #define vcpu_cp15_64_high(v,r) vcpu_cp15((v),(r))