From: Christoffer Dall Date: Thu, 9 Feb 2023 17:58:13 +0000 (+0000) Subject: KVM: arm64: nv: Handle trapped ERET from virtual EL2 X-Git-Tag: v6.6.7~3413^2~2^2^2^2~8 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=6898a55ce38c13e47a0647380504d309e9b0f631;p=platform%2Fkernel%2Flinux-starfive.git KVM: arm64: nv: Handle trapped ERET from virtual EL2 When a guest hypervisor running virtual EL2 in EL1 executes an ERET instruction, we will have set HCR_EL2.NV which traps ERET to EL2, so that we can emulate the exception return in software. Reviewed-by: Russell King (Oracle) Reviewed-by: Alexandru Elisei Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20230209175820.1939006-12-maz@kernel.org Signed-off-by: Oliver Upton --- diff --git a/arch/arm64/include/asm/esr.h b/arch/arm64/include/asm/esr.h index 206de10..d4dd949 100644 --- a/arch/arm64/include/asm/esr.h +++ b/arch/arm64/include/asm/esr.h @@ -272,6 +272,10 @@ (((e) & ESR_ELx_SYS64_ISS_OP2_MASK) >> \ ESR_ELx_SYS64_ISS_OP2_SHIFT)) +/* ISS field definitions for ERET/ERETAA/ERETAB trapping */ +#define ESR_ELx_ERET_ISS_ERET 0x2 +#define ESR_ELx_ERET_ISS_ERETA 0x1 + /* * ISS field definitions for floating-point exception traps * (FP_EXC_32/FP_EXC_64). diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index bea827b..e24825d 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -344,7 +344,7 @@ ECN(SP_ALIGN), ECN(FP_EXC32), ECN(FP_EXC64), ECN(SERROR), \ ECN(BREAKPT_LOW), ECN(BREAKPT_CUR), ECN(SOFTSTP_LOW), \ ECN(SOFTSTP_CUR), ECN(WATCHPT_LOW), ECN(WATCHPT_CUR), \ - ECN(BKPT32), ECN(VECTOR32), ECN(BRK64) + ECN(BKPT32), ECN(VECTOR32), ECN(BRK64), ECN(ERET) #define CPACR_EL1_TTA (1 << 28) #define CPACR_EL1_DEFAULT (CPACR_EL1_FPEN_EL0EN | CPACR_EL1_FPEN_EL1EN |\ diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 2d8c09c..e75101f 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -207,6 +207,15 @@ static int kvm_handle_ptrauth(struct kvm_vcpu *vcpu) return 1; } +static int kvm_handle_eret(struct kvm_vcpu *vcpu) +{ + if (kvm_vcpu_get_esr(vcpu) & ESR_ELx_ERET_ISS_ERET) + return kvm_handle_ptrauth(vcpu); + + kvm_emulate_nested_eret(vcpu); + return 1; +} + static exit_handle_fn arm_exit_handlers[] = { [0 ... ESR_ELx_EC_MAX] = kvm_handle_unknown_ec, [ESR_ELx_EC_WFx] = kvm_handle_wfx, @@ -222,6 +231,7 @@ static exit_handle_fn arm_exit_handlers[] = { [ESR_ELx_EC_SMC64] = handle_smc, [ESR_ELx_EC_SYS64] = kvm_handle_sys_reg, [ESR_ELx_EC_SVE] = handle_sve, + [ESR_ELx_EC_ERET] = kvm_handle_eret, [ESR_ELx_EC_IABT_LOW] = kvm_handle_guest_abort, [ESR_ELx_EC_DABT_LOW] = kvm_handle_guest_abort, [ESR_ELx_EC_SOFTSTP_LOW]= kvm_handle_guest_debug,