diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h index d4c7d45ae6bc..459c33634ebd 100644 --- a/arch/arm64/kernel/image-vars.h +++ b/arch/arm64/kernel/image-vars.h @@ -92,6 +92,7 @@ KVM_NVHE_ALIAS(spectre_bhb_patch_wa3); KVM_NVHE_ALIAS(spectre_bhb_patch_clearbhb); KVM_NVHE_ALIAS(alt_cb_patch_nops); KVM_NVHE_ALIAS(kvm_compute_ich_hcr_trap_bits); +KVM_NVHE_ALIAS(kvm_patch_ich_vtr_el2); /* Global kernel state accessed by nVHE hyp code. */ KVM_NVHE_ALIAS(kvm_vgic_global_state); diff --git a/arch/arm64/kvm/vgic/vgic-v3.c b/arch/arm64/kvm/vgic/vgic-v3.c index 0991a649a5d1..098187e34c58 100644 --- a/arch/arm64/kvm/vgic/vgic-v3.c +++ b/arch/arm64/kvm/vgic/vgic-v3.c @@ -858,6 +858,61 @@ void noinstr kvm_compute_ich_hcr_trap_bits(struct alt_instr *alt, *updptr = cpu_to_le32(insn); } +void noinstr kvm_patch_ich_vtr_el2(struct alt_instr *alt, + __le32 *origptr, __le32 *updptr, + int nr_inst) +{ + struct arm_smccc_res res = {}; + u32 insn, oinsn, rd, vtr; + + /* No KVM? Nothing to do */ + if (!is_hyp_mode_available()) + return; + + /* No v3, compat, nor the fruity erzatz of a GIC? Bugger off */ + if (!cpus_have_cap(ARM64_HAS_GICV5_LEGACY) && + !cpus_have_cap(ARM64_HAS_GICV3_CPUIF) && + !vgic_v3_broken_seis()) + return; + + /* + * At the point where this is called, we are guaranteed that if + * we're running at EL1, then the EL2 stubs are still in place. + */ + if (is_kernel_in_hyp_mode()) + res.a1 = read_sysreg_s(SYS_ICH_VTR_EL2); + else + arm_smccc_1_1_hvc(HVC_GET_ICH_VTR_EL2, &res); + + if (res.a0 == HVC_STUB_ERR) + return; + + vtr = res.a1; + + if (vgic_v3_broken_seis()) + vtr &= ~ICH_VTR_EL2_SEIS; + + /* Compute target register */ + oinsn = le32_to_cpu(*origptr); + rd = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RD, oinsn); + + /* movz rd, #(vtr & 0xffff) */ + insn = aarch64_insn_gen_movewide(rd, + (u16)vtr, + 0, + AARCH64_INSN_VARIANT_64BIT, + AARCH64_INSN_MOVEWIDE_ZERO); + *updptr++ = cpu_to_le32(insn); + + /* movk rd, #((vtr >> 16) & 0xffff), lsl #16 */ + insn = aarch64_insn_gen_movewide(rd, + (u16)(vtr >> 16), + 16, + AARCH64_INSN_VARIANT_64BIT, + AARCH64_INSN_MOVEWIDE_KEEP); + *updptr++ = cpu_to_le32(insn); +} + void vgic_v3_enable_cpuif_traps(void) { u64 traps = vgic_ich_hcr_trap_bits(); diff --git a/arch/arm64/kvm/vgic/vgic.h b/arch/arm64/kvm/vgic/vgic.h index f45f7e3ec4d6..b76bb6e56de3 100644 --- a/arch/arm64/kvm/vgic/vgic.h +++ b/arch/arm64/kvm/vgic/vgic.h @@ -71,6 +71,23 @@ ICH_VTR_EL2_IDbits) #define KVM_ICH_VTR_EL2_RES1 ICH_VTR_EL2_nV4 +void kvm_patch_ich_vtr_el2(struct alt_instr *alt, + __le32 *origptr, __le32 *updptr, int nr_inst); + +static inline u64 vgic_ich_vtr(void) +{ + u64 vtr; + + /* All non-RES0 bits are in the bottom 32bits */ + asm volatile(ALTERNATIVE_CB("movz %0, #0\n" + "movk %0, #0, lsl #16\n", + ARM64_ALWAYS_SYSTEM, + kvm_patch_ich_vtr_el2) + : "=r" (vtr)); + + return vtr; +} + static inline u64 kvm_get_guest_vtr_el2(void) { u64 vtr;