[PATCH 4.9 156/175] KVM: arm64: Introduce handling of AArch32 TTBCR2 traps

From: Greg Kroah-Hartman
Date: Mon Dec 28 2020 - 08:07:53 EST


From: Marc Zyngier <maz@xxxxxxxxxx>

commit ca4e514774930f30b66375a974b5edcbebaf0e7e upstream.

ARMv8.2 introduced TTBCR2, which shares TCR_EL1 with TTBCR.
Gracefully handle traps to this register when HCR_EL2.TVM is set.

Cc: stable@xxxxxxxxxxxxxxx
Reported-by: James Morse <james.morse@xxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/arm64/include/asm/kvm_host.h | 1 +
arch/arm64/kvm/sys_regs.c | 1 +
2 files changed, 2 insertions(+)

--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -161,6 +161,7 @@ enum vcpu_sysreg {
#define c2_TTBR1 (TTBR1_EL1 * 2) /* Translation Table Base Register 1 */
#define c2_TTBR1_high (c2_TTBR1 + 1) /* TTBR1 top 32 bits */
#define c2_TTBCR (TCR_EL1 * 2) /* Translation Table Base Control R. */
+#define c2_TTBCR2 (c2_TTBCR + 1) /* Translation Table Base Control R. 2 */
#define c3_DACR (DACR32_EL2 * 2)/* Domain Access Control Register */
#define c5_DFSR (ESR_EL1 * 2) /* Data Fault Status Register */
#define c5_IFSR (IFSR32_EL2 * 2)/* Instruction Fault Status Register */
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1315,6 +1315,7 @@ static const struct sys_reg_desc cp15_re
{ Op1( 0), CRn( 2), CRm( 0), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
{ Op1( 0), CRn( 2), CRm( 0), Op2( 1), access_vm_reg, NULL, c2_TTBR1 },
{ Op1( 0), CRn( 2), CRm( 0), Op2( 2), access_vm_reg, NULL, c2_TTBCR },
+ { Op1( 0), CRn( 2), CRm( 0), Op2( 3), access_vm_reg, NULL, c2_TTBCR2 },
{ Op1( 0), CRn( 3), CRm( 0), Op2( 0), access_vm_reg, NULL, c3_DACR },
{ Op1( 0), CRn( 5), CRm( 0), Op2( 0), access_vm_reg, NULL, c5_DFSR },
{ Op1( 0), CRn( 5), CRm( 0), Op2( 1), access_vm_reg, NULL, c5_IFSR },