From 9c71c33553e971b94b38a6eb261574454fea569c Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 9 Jun 2020 08:40:35 +0100 Subject: [PATCH] KVM: arm64: Make vcpu_cp1x() work on Big Endian hosts 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 Tested-by: James Morse Acked-by: James Morse Signed-off-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman --- arch/arm64/include/asm/kvm_host.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index a35ce7266aac..316533a2d0cf 100644 --- 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))