diff options
Diffstat (limited to 'arch/arm64/kvm/hyp')
| -rw-r--r-- | arch/arm64/kvm/hyp/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/aarch32.c | 4 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/exception.c | 331 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/hyp-entry.S | 71 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/include/hyp/adjust_pc.h | 62 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/include/hyp/switch.h | 17 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/include/nvhe/trap_handler.h | 18 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/Makefile | 5 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/host.S | 58 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/hyp-init.S | 152 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/hyp-main.c | 243 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/hyp-smp.c | 40 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/hyp.lds.S | 1 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/psci-relay.c | 324 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/switch.c | 8 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/sysreg-sr.c | 11 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/smccc_wa.S | 32 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/vgic-v3-sr.c | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/vhe/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm64/kvm/hyp/vhe/switch.c | 3 |
21 files changed, 1173 insertions, 215 deletions
diff --git a/arch/arm64/kvm/hyp/Makefile b/arch/arm64/kvm/hyp/Makefile index 4a81eddabcd8..687598e41b21 100644 --- a/arch/arm64/kvm/hyp/Makefile +++ b/arch/arm64/kvm/hyp/Makefile @@ -10,4 +10,4 @@ subdir-ccflags-y := -I$(incdir) \ -DDISABLE_BRANCH_PROFILING \ $(DISABLE_STACKLEAK_PLUGIN) -obj-$(CONFIG_KVM) += vhe/ nvhe/ pgtable.o smccc_wa.o +obj-$(CONFIG_KVM) += vhe/ nvhe/ pgtable.o diff --git a/arch/arm64/kvm/hyp/aarch32.c b/arch/arm64/kvm/hyp/aarch32.c index ae56d8a4b382..f98cbe2626a1 100644 --- a/arch/arm64/kvm/hyp/aarch32.c +++ b/arch/arm64/kvm/hyp/aarch32.c @@ -123,13 +123,13 @@ static void kvm_adjust_itstate(struct kvm_vcpu *vcpu) * kvm_skip_instr - skip a trapped instruction and proceed to the next * @vcpu: The vcpu pointer */ -void kvm_skip_instr32(struct kvm_vcpu *vcpu, bool is_wide_instr) +void kvm_skip_instr32(struct kvm_vcpu *vcpu) { u32 pc = *vcpu_pc(vcpu); bool is_thumb; is_thumb = !!(*vcpu_cpsr(vcpu) & PSR_AA32_T_BIT); - if (is_thumb && !is_wide_instr) + if (is_thumb && !kvm_vcpu_trap_il_is32bit(vcpu)) pc += 2; else pc += 4; diff --git a/arch/arm64/kvm/hyp/exception.c b/arch/arm64/kvm/hyp/exception.c new file mode 100644 index 000000000000..73629094f903 --- /dev/null +++ b/arch/arm64/kvm/hyp/exception.c @@ -0,0 +1,331 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Fault injection for both 32 and 64bit guests. + * + * Copyright (C) 2012,2013 - ARM Ltd + * Author: Marc Zyngier <marc.zyngier@arm.com> + * + * Based on arch/arm/kvm/emulate.c + * Copyright (C) 2012 - Virtual Open Systems and Columbia University + * Author: Christoffer Dall <c.dall@virtualopensystems.com> + */ + +#include <hyp/adjust_pc.h> +#include <linux/kvm_host.h> +#include <asm/kvm_emulate.h> + +#if !defined (__KVM_NVHE_HYPERVISOR__) && !defined (__KVM_VHE_HYPERVISOR__) +#error Hypervisor code only! +#endif + +static inline u64 __vcpu_read_sys_reg(const struct kvm_vcpu *vcpu, int reg) +{ + u64 val; + + if (__vcpu_read_sys_reg_from_cpu(reg, &val)) + return val; + + return __vcpu_sys_reg(vcpu, reg); +} + +static inline void __vcpu_write_sys_reg(struct kvm_vcpu *vcpu, u64 val, int reg) +{ + if (__vcpu_write_sys_reg_to_cpu(val, reg)) + return; + + __vcpu_sys_reg(vcpu, reg) = val; +} + +static void __vcpu_write_spsr(struct kvm_vcpu *vcpu, u64 val) +{ + write_sysreg_el1(val, SYS_SPSR); +} + +static void __vcpu_write_spsr_abt(struct kvm_vcpu *vcpu, u64 val) +{ + if (has_vhe()) + write_sysreg(val, spsr_abt); + else + vcpu->arch.ctxt.spsr_abt = val; +} + +static void __vcpu_write_spsr_und(struct kvm_vcpu *vcpu, u64 val) +{ + if (has_vhe()) + write_sysreg(val, spsr_und); + else + vcpu->arch.ctxt.spsr_und = val; +} + +/* + * This performs the exception entry at a given EL (@target_mode), stashing PC + * and PSTATE into ELR and SPSR respectively, and compute the new PC/PSTATE. + * The EL passed to this function *must* be a non-secure, privileged mode with + * bit 0 being set (PSTATE.SP == 1). + * + * When an exception is taken, most PSTATE fields are left unchanged in the + * handler. However, some are explicitly overridden (e.g. M[4:0]). Luckily all + * of the inherited bits have the same position in the AArch64/AArch32 SPSR_ELx + * layouts, so we don't need to shuffle these for exceptions from AArch32 EL0. + * + * For the SPSR_ELx layout for AArch64, see ARM DDI 0487E.a page C5-429. + * For the SPSR_ELx layout for AArch32, see ARM DDI 0487E.a page C5-426. + * + * Here we manipulate the fields in order of the AArch64 SPSR_ELx layout, from + * MSB to LSB. + */ +static void enter_exception64(struct kvm_vcpu *vcpu, unsigned long target_mode, + enum exception_type type) +{ + unsigned long sctlr, vbar, old, new, mode; + u64 exc_offset; + + mode = *vcpu_cpsr(vcpu) & (PSR_MODE_MASK | PSR_MODE32_BIT); + + if (mode == target_mode) + exc_offset = CURRENT_EL_SP_ELx_VECTOR; + else if ((mode | PSR_MODE_THREAD_BIT) == target_mode) + exc_offset = CURRENT_EL_SP_EL0_VECTOR; + else if (!(mode & PSR_MODE32_BIT)) + exc_offset = LOWER_EL_AArch64_VECTOR; + else + exc_offset = LOWER_EL_AArch32_VECTOR; + + switch (target_mode) { + case PSR_MODE_EL1h: + vbar = __vcpu_read_sys_reg(vcpu, VBAR_EL1); + sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL1); + __vcpu_write_sys_reg(vcpu, *vcpu_pc(vcpu), ELR_EL1); + break; + default: + /* Don't do that */ + BUG(); + } + + *vcpu_pc(vcpu) = vbar + exc_offset + type; + + old = *vcpu_cpsr(vcpu); + new = 0; + + new |= (old & PSR_N_BIT); + new |= (old & PSR_Z_BIT); + new |= (old & PSR_C_BIT); + new |= (old & PSR_V_BIT); + + // TODO: TCO (if/when ARMv8.5-MemTag is exposed to guests) + + new |= (old & PSR_DIT_BIT); + + // PSTATE.UAO is set to zero upon any exception to AArch64 + // See ARM DDI 0487E.a, page D5-2579. + + // PSTATE.PAN is unchanged unless SCTLR_ELx.SPAN == 0b0 + // SCTLR_ELx.SPAN is RES1 when ARMv8.1-PAN is not implemented + // See ARM DDI 0487E.a, page D5-2578. + new |= (old & PSR_PAN_BIT); + if (!(sctlr & SCTLR_EL1_SPAN)) + new |= PSR_PAN_BIT; + + // PSTATE.SS is set to zero upon any exception to AArch64 + // See ARM DDI 0487E.a, page D2-2452. + + // PSTATE.IL is set to zero upon any exception to AArch64 + // See ARM DDI 0487E.a, page D1-2306. + + // PSTATE.SSBS is set to SCTLR_ELx.DSSBS upon any exception to AArch64 + // See ARM DDI 0487E.a, page D13-3258 + if (sctlr & SCTLR_ELx_DSSBS) + new |= PSR_SSBS_BIT; + + // PSTATE.BTYPE is set to zero upon any exception to AArch64 + // See ARM DDI 0487E.a, pages D1-2293 to D1-2294. + + new |= PSR_D_BIT; + new |= PSR_A_BIT; + new |= PSR_I_BIT; + new |= PSR_F_BIT; + + new |= target_mode; + + *vcpu_cpsr(vcpu) = new; + __vcpu_write_spsr(vcpu, old); +} + +/* + * When an exception is taken, most CPSR fields are left unchanged in the + * handler. However, some are explicitly overridden (e.g. M[4:0]). + * + * The SPSR/SPSR_ELx layouts differ, and the below is intended to work with + * either format. Note: SPSR.J bit doesn't exist in SPSR_ELx, but this bit was + * obsoleted by the ARMv7 virtualization extensions and is RES0. + * + * For the SPSR layout seen from AArch32, see: + * - ARM DDI 0406C.d, page B1-1148 + * - ARM DDI 0487E.a, page G8-6264 + * + * For the SPSR_ELx layout for AArch32 seen from AArch64, see: + * - ARM DDI 0487E.a, page C5-426 + * + * Here we manipulate the fields in order of the AArch32 SPSR_ELx layout, from + * MSB to LSB. + */ +static unsigned long get_except32_cpsr(struct kvm_vcpu *vcpu, u32 mode) +{ + u32 sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL1); + unsigned long old, new; + + old = *vcpu_cpsr(vcpu); + new = 0; + + new |= (old & PSR_AA32_N_BIT); + new |= (old & PSR_AA32_Z_BIT); + new |= (old & PSR_AA32_C_BIT); + new |= (old & PSR_AA32_V_BIT); + new |= (old & PSR_AA32_Q_BIT); + + // CPSR.IT[7:0] are set to zero upon any exception + // See ARM DDI 0487E.a, section G1.12.3 + // See ARM DDI 0406C.d, section B1.8.3 + + new |= (old & PSR_AA32_DIT_BIT); + + // CPSR.SSBS is set to SCTLR.DSSBS upon any exception + // See ARM DDI 0487E.a, page G8-6244 + if (sctlr & BIT(31)) + new |= PSR_AA32_SSBS_BIT; + + // CPSR.PAN is unchanged unless SCTLR.SPAN == 0b0 + // SCTLR.SPAN is RES1 when ARMv8.1-PAN is not implemented + // See ARM DDI 0487E.a, page G8-6246 + new |= (old & PSR_AA32_PAN_BIT); + if (!(sctlr & BIT(23))) + new |= PSR_AA32_PAN_BIT; + + // SS does not exist in AArch32, so ignore + + // CPSR.IL is set to zero upon any exception + // See ARM DDI 0487E.a, page G1-5527 + + new |= (old & PSR_AA32_GE_MASK); + + // CPSR.IT[7:0] are set to zero upon any exception + // See prior comment above + + // CPSR.E is set to SCTLR.EE upon any exception + // See ARM DDI 0487E.a, page G8-6245 + // See ARM DDI 0406C.d, page B4-1701 + if (sctlr & BIT(25)) + new |= PSR_AA32_E_BIT; + + // CPSR.A is unchanged upon an exception to Undefined, Supervisor + // CPSR.A is set upon an exception to other modes + // See ARM DDI 0487E.a, pages G1-5515 to G1-5516 + // See ARM DDI 0406C.d, page B1-1182 + new |= (old & PSR_AA32_A_BIT); + if (mode != PSR_AA32_MODE_UND && mode != PSR_AA32_MODE_SVC) + new |= PSR_AA32_A_BIT; + + // CPSR.I is set upon any exception + // See ARM DDI 0487E.a, pages G1-5515 to G1-5516 + // See ARM DDI 0406C.d, page B1-1182 + new |= PSR_AA32_I_BIT; + + // CPSR.F is set upon an exception to FIQ + // CPSR.F is unchanged upon an exception to other modes + // See ARM DDI 0487E.a, pages G1-5515 to G1-5516 + // See ARM DDI 0406C.d, page B1-1182 + new |= (old & PSR_AA32_F_BIT); + if (mode == PSR_AA32_MODE_FIQ) + new |= PSR_AA32_F_BIT; + + // CPSR.T is set to SCTLR.TE upon any exception + // See ARM DDI 0487E.a, page G8-5514 + // See ARM DDI 0406C.d, page B1-1181 + if (sctlr & BIT(30)) + new |= PSR_AA32_T_BIT; + + new |= mode; + + return new; +} + +/* + * Table taken from ARMv8 ARM DDI0487B-B, table G1-10. + */ +static const u8 return_offsets[8][2] = { + [0] = { 0, 0 }, /* Reset, unused */ + [1] = { 4, 2 }, /* Undefined */ + [2] = { 0, 0 }, /* SVC, unused */ + [3] = { 4, 4 }, /* Prefetch abort */ + [4] = { 8, 8 }, /* Data abort */ + [5] = { 0, 0 }, /* HVC, unused */ + [6] = { 4, 4 }, /* IRQ, unused */ + [7] = { 4, 4 }, /* FIQ, unused */ +}; + +static void enter_exception32(struct kvm_vcpu *vcpu, u32 mode, u32 vect_offset) +{ + unsigned long spsr = *vcpu_cpsr(vcpu); + bool is_thumb = (spsr & PSR_AA32_T_BIT); + u32 sctlr = __vcpu_read_sys_reg(vcpu, SCTLR_EL1); + u32 return_address; + + *vcpu_cpsr(vcpu) = get_except32_cpsr(vcpu, mode); + return_address = *vcpu_pc(vcpu); + return_address += return_offsets[vect_offset >> 2][is_thumb]; + + /* KVM only enters the ABT and UND modes, so only deal with those */ + switch(mode) { + case PSR_AA32_MODE_ABT: + __vcpu_write_spsr_abt(vcpu, host_spsr_to_spsr32(spsr)); + vcpu_gp_regs(vcpu)->compat_lr_abt = return_address; + break; + + case PSR_AA32_MODE_UND: + __vcpu_write_spsr_und(vcpu, host_spsr_to_spsr32(spsr)); + vcpu_gp_regs(vcpu)->compat_lr_und = return_address; + break; + } + + /* Branch to exception vector */ + if (sctlr & (1 << 13)) + vect_offset += 0xffff0000; + else /* always have security exceptions */ + vect_offset += __vcpu_read_sys_reg(vcpu, VBAR_EL1); + + *vcpu_pc(vcpu) = vect_offset; +} + +void kvm_inject_exception(struct kvm_vcpu *vcpu) +{ + if (vcpu_el1_is_32bit(vcpu)) { + switch (vcpu->arch.flags & KVM_ARM64_EXCEPT_MASK) { + case KVM_ARM64_EXCEPT_AA32_UND: + enter_exception32(vcpu, PSR_AA32_MODE_UND, 4); + break; + case KVM_ARM64_EXCEPT_AA32_IABT: + enter_exception32(vcpu, PSR_AA32_MODE_ABT, 12); + break; + case KVM_ARM64_EXCEPT_AA32_DABT: + enter_exception32(vcpu, PSR_AA32_MODE_ABT, 16); + break; + default: + /* Err... */ + break; + } + } else { + switch (vcpu->arch.flags & KVM_ARM64_EXCEPT_MASK) { + case (KVM_ARM64_EXCEPT_AA64_ELx_SYNC | + KVM_ARM64_EXCEPT_AA64_EL1): + enter_exception64(vcpu, PSR_MODE_EL1h, except_type_sync); + break; + default: + /* + * Only EL1_SYNC makes sense so far, EL2_{SYNC,IRQ} + * will be implemented at some point. Everything + * else gets silently ignored. + */ + break; + } + } +} diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S index 0a5b36eb54b3..d179056e1af8 100644 --- a/arch/arm64/kvm/hyp/hyp-entry.S +++ b/arch/arm64/kvm/hyp/hyp-entry.S @@ -13,6 +13,7 @@ #include <asm/kvm_arm.h> #include <asm/kvm_asm.h> #include <asm/mmu.h> +#include <asm/spectre.h> .macro save_caller_saved_regs_vect /* x0 and x1 were saved in the vector entry */ @@ -187,52 +188,60 @@ SYM_CODE_START(__kvm_hyp_vector) valid_vect el1_error // Error 32-bit EL1 SYM_CODE_END(__kvm_hyp_vector) -.macro hyp_ventry - .align 7 +.macro spectrev2_smccc_wa1_smc + sub sp, sp, #(8 * 4) + stp x2, x3, [sp, #(8 * 0)] + stp x0, x1, [sp, #(8 * 2)] + mov w0, #ARM_SMCCC_ARCH_WORKAROUND_1 + smc #0 + ldp x2, x3, [sp, #(8 * 0)] + add sp, sp, #(8 * 2) +.endm + +.macro hyp_ventry indirect, spectrev2 + .align 7 1: esb - .rept 26 - nop - .endr -/* - * The default sequence is to directly branch to the KVM vectors, - * using the computed offset. This applies for VHE as well as - * !ARM64_HARDEN_EL2_VECTORS. The first vector must always run the preamble. - * - * For ARM64_HARDEN_EL2_VECTORS configurations, this gets replaced - * with: - * - * stp x0, x1, [sp, #-16]! - * movz x0, #(addr & 0xffff) - * movk x0, #((addr >> 16) & 0xffff), lsl #16 - * movk x0, #((addr >> 32) & 0xffff), lsl #32 - * br x0 - * - * Where: - * addr = kern_hyp_va(__kvm_hyp_vector) + vector-offset + KVM_VECTOR_PREAMBLE. - * See kvm_patch_vector_branch for details. - */ -alternative_cb kvm_patch_vector_branch + .if \spectrev2 != 0 + spectrev2_smccc_wa1_smc + .else stp x0, x1, [sp, #-16]! - b __kvm_hyp_vector + (1b - 0b + KVM_VECTOR_PREAMBLE) + .endif + .if \indirect != 0 + alternative_cb kvm_patch_vector_branch + /* + * For ARM64_SPECTRE_V3A configurations, these NOPs get replaced with: + * + * movz x0, #(addr & 0xffff) + * movk x0, #((addr >> 16) & 0xffff), lsl #16 + * movk x0, #((addr >> 32) & 0xffff), lsl #32 + * br x0 + * + * Where: + * addr = kern_hyp_va(__kvm_hyp_vector) + vector-offset + KVM_VECTOR_PREAMBLE. + * See kvm_patch_vector_branch for details. + */ nop nop nop -alternative_cb_end + nop + alternative_cb_end + .endif + b __kvm_hyp_vector + (1b - 0b + KVM_VECTOR_PREAMBLE) .endm -.macro generate_vectors +.macro generate_vectors indirect, spectrev2 0: .rept 16 - hyp_ventry + hyp_ventry \indirect, \spectrev2 .endr .org 0b + SZ_2K // Safety measure .endm .align 11 SYM_CODE_START(__bp_harden_hyp_vecs) - .rept BP_HARDEN_EL2_SLOTS - generate_vectors - .endr + generate_vectors indirect = 0, spectrev2 = 1 // HYP_VECTOR_SPECTRE_DIRECT + generate_vectors indirect = 1, spectrev2 = 0 // HYP_VECTOR_INDIRECT + generate_vectors indirect = 1, spectrev2 = 1 // HYP_VECTOR_SPECTRE_INDIRECT 1: .org __bp_harden_hyp_vecs + __BP_HARDEN_HYP_VECS_SZ .org 1b SYM_CODE_END(__bp_harden_hyp_vecs) diff --git a/arch/arm64/kvm/hyp/include/hyp/adjust_pc.h b/arch/arm64/kvm/hyp/include/hyp/adjust_pc.h new file mode 100644 index 000000000000..b1f60923a8fe --- /dev/null +++ b/arch/arm64/kvm/hyp/include/hyp/adjust_pc.h @@ -0,0 +1,62 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Guest PC manipulation helpers + * + * Copyright (C) 2012,2013 - ARM Ltd + * Copyright (C) 2020 - Google LLC + * Author: Marc Zyngier <maz@kernel.org> + */ + +#ifndef __ARM64_KVM_HYP_ADJUST_PC_H__ +#define __ARM64_KVM_HYP_ADJUST_PC_H__ + +#include <asm/kvm_emulate.h> +#include <asm/kvm_host.h> + +void kvm_inject_exception(struct kvm_vcpu *vcpu); + +static inline void kvm_skip_instr(struct kvm_vcpu *vcpu) +{ + if (vcpu_mode_is_32bit(vcpu)) { + kvm_skip_instr32(vcpu); + } else { + *vcpu_pc(vcpu) += 4; + *vcpu_cpsr(vcpu) &= ~PSR_BTYPE_MASK; + } + + /* advance the singlestep state machine */ + *vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS; +} + +/* + * Skip an instruction which has been emulated at hyp while most guest sysregs + * are live. + */ +static inline void __kvm_skip_instr(struct kvm_vcpu *vcpu) +{ + *vcpu_pc(vcpu) = read_sysreg_el2(SYS_ELR); + vcpu_gp_regs(vcpu)->pstate = read_sysreg_el2(SYS_SPSR); + + kvm_skip_instr(vcpu); + + write_sysreg_el2(vcpu_gp_regs(vcpu)->pstate, SYS_SPSR); + write_sysreg_el2(*vcpu_pc(vcpu), SYS_ELR); +} + +/* + * Adjust the guest PC on entry, depending on flags provided by EL1 + * for the purpose of emulation (MMIO, sysreg) or exception injection. + */ +static inline void __adjust_pc(struct kvm_vcpu *vcpu) +{ + if (vcpu->arch.flags & KVM_ARM64_PENDING_EXCEPTION) { + kvm_inject_exception(vcpu); + vcpu->arch.flags &= ~(KVM_ARM64_PENDING_EXCEPTION | + KVM_ARM64_EXCEPT_MASK); + } else if (vcpu->arch.flags & KVM_ARM64_INCREMENT_PC) { + kvm_skip_instr(vcpu); + vcpu->arch.flags &= ~KVM_ARM64_INCREMENT_PC; + } +} + +#endif diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h index 1f875a8f20c4..84473574c2e7 100644 --- a/arch/arm64/kvm/hyp/include/hyp/switch.h +++ b/arch/arm64/kvm/hyp/include/hyp/switch.h @@ -7,6 +7,8 @@ #ifndef __ARM64_KVM_HYP_SWITCH_H__ #define __ARM64_KVM_HYP_SWITCH_H__ +#include <hyp/adjust_pc.h> + #include <linux/arm-smccc.h> #include <linux/kvm_host.h> #include <linux/types.h> @@ -409,6 +411,21 @@ static inline bool fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code) if (ARM_EXCEPTION_CODE(*exit_code) != ARM_EXCEPTION_IRQ) vcpu->arch.fault.esr_el2 = read_sysreg_el2(SYS_ESR); + if (ARM_SERROR_PENDING(*exit_code)) { + u8 esr_ec = kvm_vcpu_trap_get_class(vcpu); + + /* + * HVC already have an adjusted PC, which we need to + * correct in order to return to after having injected + * the SError. + * + * SMC, on the other hand, is *trapped*, meaning its + * preferred return address is the SMC itself. + */ + if (esr_ec == ESR_ELx_EC_HVC32 || esr_ec == ESR_ELx_EC_HVC64) + write_sysreg_el2(read_sysreg_el2(SYS_ELR) - 4, SYS_ELR); + } + /* * We're using the raw exception code in order to only process * the trap if no SError is pending. We will come back to the diff --git a/arch/arm64/kvm/hyp/include/nvhe/trap_handler.h b/arch/arm64/kvm/hyp/include/nvhe/trap_handler.h new file mode 100644 index 000000000000..1e6d995968a1 --- /dev/null +++ b/arch/arm64/kvm/hyp/include/nvhe/trap_handler.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Trap handler helpers. + * + * Copyright (C) 2020 - Google LLC + * Author: Marc Zyngier <maz@kernel.org> + */ + +#ifndef __ARM64_KVM_NVHE_TRAP_HANDLER_H__ +#define __ARM64_KVM_NVHE_TRAP_HANDLER_H__ + +#include <asm/kvm_host.h> + +#define cpu_reg(ctxt, r) (ctxt)->regs.regs[r] +#define DECLARE_REG(type, name, ctxt, reg) \ + type name = (type)cpu_reg(ctxt, (reg)) + +#endif /* __ARM64_KVM_NVHE_TRAP_HANDLER_H__ */ diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index ddde15fe85f2..1f1e351c5fe2 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -6,9 +6,10 @@ asflags-y := -D__KVM_NVHE_HYPERVISOR__ ccflags-y := -D__KVM_NVHE_HYPERVISOR__ -obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o hyp-main.o +obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \ + hyp-main.o hyp-smp.o psci-relay.o obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \ - ../fpsimd.o ../hyp-entry.o + ../fpsimd.o ../hyp-entry.o ../exception.o ## ## Build rules for compiling nVHE hyp code diff --git a/arch/arm64/kvm/hyp/nvhe/host.S b/arch/arm64/kvm/hyp/nvhe/host.S index ed27f06a31ba..a820dfdc9c25 100644 --- a/arch/arm64/kvm/hyp/nvhe/host.S +++ b/arch/arm64/kvm/hyp/nvhe/host.S @@ -13,8 +13,6 @@ .text SYM_FUNC_START(__host_exit) - stp x0, x1, [sp, #-16]! - get_host_ctxt x0, x1 /* Store the host regs x2 and x3 */ @@ -41,6 +39,7 @@ SYM_FUNC_START(__host_exit) bl handle_trap /* Restore host regs x0-x17 */ +__host_enter_restore_full: ldp x0, x1, [x29, #CPU_XREG_OFFSET(0)] ldp x2, x3, [x29, #CPU_XREG_OFFSET(2)] ldp x4, x5, [x29, #CPU_XREG_OFFSET(4)] @@ -64,6 +63,14 @@ __host_enter_without_restoring: SYM_FUNC_END(__host_exit) /* + * void __noreturn __host_enter(struct kvm_cpu_context *host_ctxt); + */ +SYM_FUNC_START(__host_enter) + mov x29, x0 + b __host_enter_restore_full +SYM_FUNC_END(__host_enter) + +/* * void __noreturn __hyp_do_panic(bool restore_host, u64 spsr, u64 elr, u64 par); */ SYM_FUNC_START(__hyp_do_panic) @@ -99,13 +106,15 @@ SYM_FUNC_END(__hyp_do_panic) mrs x0, esr_el2 lsr x0, x0, #ESR_ELx_EC_SHIFT cmp x0, #ESR_ELx_EC_HVC64 - ldp x0, x1, [sp], #16 b.ne __host_exit + ldp x0, x1, [sp] // Don't fixup the stack yet + /* Check for a stub HVC call */ cmp x0, #HVC_STUB_HCALL_NR b.hs __host_exit + add sp, sp, #16 /* * Compute the idmap address of __kvm_handle_stub_hvc and * jump there. Since we use kimage_voffset, do not use the @@ -115,10 +124,7 @@ SYM_FUNC_END(__hyp_do_panic) * Preserve x0-x4, which may contain stub parameters. */ ldr x5, =__kvm_handle_stub_hvc - ldr_l x6, kimage_voffset - - /* x5 = __pa(x5) */ - sub x5, x5, x6 + kimg_pa x5, x6 br x5 .L__vect_end\@: .if ((.L__vect_end\@ - .L__vect_start\@) > 0x80) @@ -183,3 +189,41 @@ SYM_CODE_START(__kvm_hyp_host_vector) invalid_host_el1_vect // FIQ 32-bit EL1 invalid_host_el1_vect // Error 32-bit EL1 SYM_CODE_END(__kvm_hyp_host_vector) + +/* + * Forward SMC with arguments in struct kvm_cpu_context, and + * store the result into the same struct. Assumes SMCCC 1.2 or older. + * + * x0: struct kvm_cpu_context* + */ +SYM_CODE_START(__kvm_hyp_host_forward_smc) + /* + * Use x18 to keep the pointer to the host context because + * x18 is callee-saved in SMCCC but not in AAPCS64. + */ + mov x18, x0 + + ldp x0, x1, [x18, #CPU_XREG_OFFSET(0)] + ldp x2, x3, [x18, #CPU_XREG_OFFSET(2)] + ldp x4, x5, [x18, #CPU_XREG_OFFSET(4)] + ldp x6, x7, [x18, #CPU_XREG_OFFSET(6)] + ldp x8, x9, [x18, #CPU_XREG_OFFSET(8)] + ldp x10, x11, [x18, #CPU_XREG_OFFSET(10)] + ldp x12, x13, [x18, #CPU_XREG_OFFSET(12)] + ldp x14, x15, [x18, #CPU_XREG_OFFSET(14)] + ldp x16, x17, [x18, #CPU_XREG_OFFSET(16)] + + smc #0 + + stp x0, x1, [x18, #CPU_XREG_OFFSET(0)] + stp x2, x3, [x18, #CPU_XREG_OFFSET(2)] + stp x4, x5, [x18, #CPU_XREG_OFFSET(4)] + stp x6, x7, [x18, #CPU_XREG_OFFSET(6)] + stp x8, x9, [x18, #CPU_XREG_OFFSET(8)] + stp x10, x11, [x18, #CPU_XREG_OFFSET(10)] + stp x12, x13, [x18, #CPU_XREG_OFFSET(12)] + stp x14, x15, [x18, #CPU_XREG_OFFSET(14)] + stp x16, x17, [x18, #CPU_XREG_OFFSET(16)] + + ret +SYM_CODE_END(__kvm_hyp_host_forward_smc) diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-init.S b/arch/arm64/kvm/hyp/nvhe/hyp-init.S index b11a9d7db677..31b060a44045 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-init.S +++ b/arch/arm64/kvm/hyp/nvhe/hyp-init.S @@ -9,6 +9,7 @@ #include <asm/alternative.h> #include <asm/assembler.h> +#include <asm/el2_setup.h> #include <asm/kvm_arm.h> #include <asm/kvm_asm.h> #include <asm/kvm_mmu.h> @@ -47,10 +48,7 @@ __invalid: /* * x0: SMCCC function ID - * x1: HYP pgd - * x2: per-CPU offset - * x3: HYP stack - * x4: HYP vectors + * x1: struct kvm_nvhe_init_params PA */ __do_hyp_init: /* Check for a stub HVC call */ @@ -71,48 +69,53 @@ __do_hyp_init: mov x0, #SMCCC_RET_NOT_SUPPORTED eret -1: - /* Set tpidr_el2 for use by HYP to free a register */ - msr tpidr_el2, x2 +1: mov x0, x1 + mov x4, lr + bl ___kvm_hyp_init + mov lr, x4 - phys_to_ttbr x0, x1 -alternative_if ARM64_HAS_CNP - orr x0, x0, #TTBR_CNP_BIT + /* Hello, World! */ + mov x0, #SMCCC_RET_SUCCESS + eret +SYM_CODE_END(__kvm_hyp_init) + +/* + * Initialize the hypervisor in EL2. + * + * Only uses x0..x3 so as to not clobber callee-saved SMCCC registers + * and leave x4 for the caller. + * + * x0: struct kvm_nvhe_init_params PA + */ +SYM_CODE_START_LOCAL(___kvm_hyp_init) +alternative_if ARM64_KVM_PROTECTED_MODE + mov_q x1, HCR_HOST_NVHE_PROTECTED_FLAGS + msr hcr_el2, x1 alternative_else_nop_endif - msr ttbr0_el2, x0 - mrs x0, tcr_el1 - mov_q x1, TCR_EL2_MASK - and x0, x0, x1 - mov x1, #TCR_EL2_RES1 - orr x0, x0, x1 + ldr x1, [x0, #NVHE_INIT_TPIDR_EL2] + msr tpidr_el2, x1 - /* - * The ID map may be configured to use an extended virtual address - * range. This is only the case if system RAM is out of range for the - * currently configured page size and VA_BITS, in which case we will - * also need the extended virtual range for the HYP ID map, or we won't - * be able to enable the EL2 MMU. - * - * However, at EL2, there is only one TTBR register, and we can't switch - * between translation tables *and* update TCR_EL2.T0SZ at the same - * time. Bottom line: we need to use the extended range with *both* our - * translation tables. - * - * So use the same T0SZ value we use for the ID map. - */ - ldr_l x1, idmap_t0sz - bfi x0, x1, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH + ldr x1, [x0, #NVHE_INIT_STACK_HYP_VA] + mov sp, x1 + + ldr x1, [x0, #NVHE_INIT_MAIR_EL2] + msr mair_el2, x1 + + ldr x1, [x0, #NVHE_INIT_PGD_PA] + phys_to_ttbr x2, x1 +alternative_if ARM64_HAS_CNP + orr x2, x2, #TTBR_CNP_BIT +alternative_else_nop_endif + msr ttbr0_el2, x2 /* * Set the PS bits in TCR_EL2. */ - tcr_compute_pa_size x0, #TCR_EL2_PS_SHIFT, x1, x2 + ldr x1, [x0, #NVHE_INIT_TCR_EL2] + tcr_compute_pa_size x1, #TCR_EL2_PS_SHIFT, x2, x3 + msr tcr_el2, x1 - msr tcr_el2, x0 - - mrs x0, mair_el1 - msr mair_el2, x0 isb /* Invalidate the stale TLBs from Bootloader */ @@ -134,14 +137,70 @@ alternative_else_nop_endif msr sctlr_el2, x0 isb - /* Set the stack and new vectors */ - mov sp, x3 - msr vbar_el2, x4 + /* Set the host vector */ + ldr x0, =__kvm_hyp_host_vector + kimg_hyp_va x0, x1 + msr vbar_el2, x0 - /* Hello, World! */ - mov x0, #SMCCC_RET_SUCCESS - eret -SYM_CODE_END(__kvm_hyp_init) + ret +SYM_CODE_END(___kvm_hyp_init) + +/* + * PSCI CPU_ON entry point + * + * x0: struct kvm_nvhe_init_params PA + */ +SYM_CODE_START(kvm_hyp_cpu_entry) + mov x1, #1 // is_cpu_on = true + b __kvm_hyp_init_cpu +SYM_CODE_END(kvm_hyp_cpu_entry) + +/* + * PSCI CPU_SUSPEND / SYSTEM_SUSPEND entry point + * + * x0: struct kvm_nvhe_init_params PA + */ +SYM_CODE_START(kvm_hyp_cpu_resume) + mov x1, #0 // is_cpu_on = false + b __kvm_hyp_init_cpu +SYM_CODE_END(kvm_hyp_cpu_resume) + +/* + * Common code for CPU entry points. Initializes EL2 state and + * installs the hypervisor before handing over to a C handler. + * + * x0: struct kvm_nvhe_init_params PA + * x1: bool is_cpu_on + */ +SYM_CODE_START_LOCAL(__kvm_hyp_init_cpu) + mov x28, x0 // Stash arguments + mov x29, x1 + + /* Check that the core was booted in EL2. */ + mrs x0, CurrentEL + cmp x0, #CurrentEL_EL2 + b.eq 2f + + /* The core booted in EL1. KVM cannot be initialized on it. */ +1: wfe + wfi + b 1b + +2: msr SPsel, #1 // We want to use SP_EL{1,2} + + /* Initialize EL2 CPU state to sane values. */ + init_el2_state nvhe // Clobbers x0..x2 + + /* Enable MMU, set vectors and stack. */ + mov x0, x28 + bl ___kvm_hyp_init // Clobbers x0..x3 + + /* Leave idmap. */ + mov x0, x29 + ldr x1, =kvm_host_psci_cpu_entry + kimg_hyp_va x1, x2 + br x1 +SYM_CODE_END(__kvm_hyp_init_cpu) SYM_CODE_START(__kvm_handle_stub_hvc) cmp x0, #HVC_SOFT_RESTART @@ -176,6 +235,11 @@ reset: msr sctlr_el2, x5 isb +alternative_if ARM64_KVM_PROTECTED_MODE + mov_q x5, HCR_HOST_NVHE_FLAGS + msr hcr_el2, x5 +alternative_else_nop_endif + /* Install stub vectors */ adr_l x5, __hyp_stub_vectors msr vbar_el2, x5 diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c index e2eafe2c93af..bde658d51404 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -12,106 +12,183 @@ #include <asm/kvm_hyp.h> #include <asm/kvm_mmu.h> -#include <kvm/arm_hypercalls.h> +#include <nvhe/trap_handler.h> -static void handle_host_hcall(unsigned long func_id, - struct kvm_cpu_context *host_ctxt) +DEFINE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params); + +void __kvm_hyp_host_forward_smc(struct kvm_cpu_context *host_ctxt); + +static void handle___kvm_vcpu_run(struct kvm_cpu_context *host_ctxt) { - unsigned long ret = 0; + DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1); - switch (func_id) { - case KVM_HOST_SMCCC_FUNC(__kvm_vcpu_run): { - unsigned long r1 = host_ctxt->regs.regs[1]; - struct kvm_vcpu *vcpu = (struct kvm_vcpu *)r1; + cpu_reg(host_ctxt, 1) = __kvm_vcpu_run(kern_hyp_va(vcpu)); +} - ret = __kvm_vcpu_run(kern_hyp_va(vcpu)); - break; - } - case KVM_HOST_SMCCC_FUNC(__kvm_flush_vm_context): - __kvm_flush_vm_context(); - break; - case KVM_HOST_SMCCC_FUNC(__kvm_tlb_flush_vmid_ipa): { - unsigned long r1 = host_ctxt->regs.regs[1]; - struct kvm_s2_mmu *mmu = (struct kvm_s2_mmu *)r1; - phys_addr_t ipa = host_ctxt->regs.regs[2]; - int level = host_ctxt->regs.regs[3]; +static void handle___kvm_flush_vm_context(struct kvm_cpu_context *host_ctxt) +{ + __kvm_flush_vm_context(); +} - __kvm_tlb_flush_vmid_ipa(kern_hyp_va(mmu), ipa, level); - break; - } - case KVM_HOST_SMCCC_FUNC(__kvm_tlb_flush_vmid): { - unsigned long r1 = host_ctxt->regs.regs[1]; - struct kvm_s2_mmu *mmu = (struct kvm_s2_mmu *)r1; +static void handle___kvm_tlb_flush_vmid_ipa(struct kvm_cpu_context *host_ctxt) +{ + DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); + DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2); + DECLARE_REG(int, level, host_ctxt, 3); - __kvm_tlb_flush_vmid(kern_hyp_va(mmu)); - break; - } - case KVM_HOST_SMCCC_FUNC(__kvm_tlb_flush_local_vmid): { - unsigned long r1 = host_ctxt->regs.regs[1]; - struct kvm_s2_mmu *mmu = (struct kvm_s2_mmu *)r1; + __kvm_tlb_flush_vmid_ipa(kern_hyp_va(mmu), ipa, level); +} - __kvm_tlb_flush_local_vmid(kern_hyp_va(mmu)); - break; - } - case KVM_HOST_SMCCC_FUNC(__kvm_timer_set_cntvoff): { - u64 cntvoff = host_ctxt->regs.regs[1]; +static void handle___kvm_tlb_flush_vmid(struct kvm_cpu_context *host_ctxt) +{ + DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); - __kvm_timer_set_cntvoff(cntvoff); - break; - } - case KVM_HOST_SMCCC_FUNC(__kvm_enable_ssbs): - __kvm_enable_ssbs(); - break; - case KVM_HOST_SMCCC_FUNC(__vgic_v3_get_ich_vtr_el2): - ret = __vgic_v3_get_ich_vtr_el2(); - break; - case KVM_HOST_SMCCC_FUNC(__vgic_v3_read_vmcr): - ret = __vgic_v3_read_vmcr(); - break; - case KVM_HOST_SMCCC_FUNC(__vgic_v3_write_vmcr): { - u32 vmcr = host_ctxt->regs.regs[1]; + __kvm_tlb_flush_vmid(kern_hyp_va(mmu)); +} - __vgic_v3_write_vmcr(vmcr); - break; - } - case KVM_HOST_SMCCC_FUNC(__vgic_v3_init_lrs): - __vgic_v3_init_lrs(); - break; - case KVM_HOST_SMCCC_FUNC(__kvm_get_mdcr_el2): - ret = __kvm_get_mdcr_el2(); - break; - case KVM_HOST_SMCCC_FUNC(__vgic_v3_save_aprs): { - unsigned long r1 = host_ctxt->regs.regs[1]; - struct vgic_v3_cpu_if *cpu_if = (struct vgic_v3_cpu_if *)r1; +static void handle___kvm_tlb_flush_local_vmid(struct kvm_cpu_context *host_ctxt) +{ + DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); - __vgic_v3_save_aprs(kern_hyp_va(cpu_if)); - break; - } - case KVM_HOST_SMCCC_FUNC(__vgic_v3_restore_aprs): { - unsigned long r1 = host_ctxt->regs.regs[1]; - struct vgic_v3_cpu_if *cpu_if = (struct vgic_v3_cpu_if *)r1; + __kvm_tlb_flush_local_vmid(kern_hyp_va(mmu)); +} - __vgic_v3_restore_aprs(kern_hyp_va(cpu_if)); - break; - } - default: - /* Invalid host HVC. */ - host_ctxt->regs.regs[0] = SMCCC_RET_NOT_SUPPORTED; - return; - } +static void handle___kvm_timer_set_cntvoff(struct kvm_cpu_context *host_ctxt) +{ + __kvm_timer_set_cntvoff(cpu_reg(host_ctxt, 1)); +} + +static void handle___kvm_enable_ssbs(struct kvm_cpu_context *host_ctxt) +{ + u64 tmp; - host_ctxt->regs.regs[0] = SMCCC_RET_SUCCESS; - host_ctxt->regs.regs[1] = ret; + tmp = read_sysreg_el2(SYS_SCTLR); + tmp |= SCTLR_ELx_DSSBS; + write_sysreg_el2(tmp, SYS_SCTLR); +} + +static void handle___vgic_v3_get_ich_vtr_el2(struct kvm_cpu_context *host_ctxt) +{ + cpu_reg(host_ctxt, 1) = __vgic_v3_get_ich_vtr_el2(); +} + +static void handle___vgic_v3_read_vmcr(struct kvm_cpu_context *host_ctxt) +{ + cpu_reg(host_ctxt, 1) = __vgic_v3_read_vmcr(); +} + +static void handle___vgic_v3_write_vmcr(struct kvm_cpu_context *host_ctxt) +{ + __vgic_v3_write_vmcr(cpu_reg(host_ctxt, 1)); +} + +static void handle___vgic_v3_init_lrs(struct kvm_cpu_context *host_ctxt) +{ + __vgic_v3_init_lrs(); +} + +static void handle___kvm_get_mdcr_el2(struct kvm_cpu_context *host_ctxt) +{ + cpu_reg(host_ctxt, 1) = __kvm_get_mdcr_el2(); +} + +static void handle___vgic_v3_save_aprs(struct kvm_cpu_context *host_ctxt) +{ + DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1); + + __vgic_v3_save_aprs(kern_hyp_va(cpu_if)); +} + +static void handle___vgic_v3_restore_aprs(struct kvm_cpu_context *host_ctxt) +{ + DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1); + + __vgic_v3_restore_aprs(kern_hyp_va(cpu_if)); +} + +typedef void (*hcall_t)(struct kvm_cpu_context *); + +#define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = kimg_fn_ptr(handle_##x) + +static const hcall_t *host_hcall[] = { + HANDLE_FUNC(__kvm_vcpu_run), + HANDLE_FUNC(__kvm_flush_vm_context), + HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa), + HANDLE_FUNC(__kvm_tlb_flush_vmid), + HANDLE_FUNC(__kvm_tlb_flush_local_vmid), + HANDLE_FUNC(__kvm_timer_set_cntvoff), + HANDLE_FUNC(__kvm_enable_ssbs), + HANDLE_FUNC(__vgic_v3_get_ich_vtr_el2), + HANDLE_FUNC(__vgic_v3_read_vmcr), + HANDLE_FUNC(__vgic_v3_write_vmcr), + HANDLE_FUNC(__vgic_v3_init_lrs), + HANDLE_FUNC(__kvm_get_mdcr_el2), + HANDLE_FUNC(__vgic_v3_save_aprs), + HANDLE_FUNC(__vgic_v3_restore_aprs), +}; + +static void handle_host_hcall(struct kvm_cpu_context *host_ctxt) +{ + DECLARE_REG(unsigned long, id, host_ctxt, 0); + const hcall_t *kfn; + hcall_t hfn; + + id -= KVM_HOST_SMCCC_ID(0); + + if (unlikely(id >= ARRAY_SIZE(host_hcall))) + goto inval; + + kfn = host_hcall[id]; + if (unlikely(!kfn)) + goto inval; + + cpu_reg(host_ctxt, 0) = SMCCC_RET_SUCCESS; + + hfn = kimg_fn_hyp_va(kfn); + hfn(host_ctxt); + + return; +inval: + cpu_reg(host_ctxt, 0) = SMCCC_RET_NOT_SUPPORTED; +} + +static void default_host_smc_handler(struct kvm_cpu_context *host_ctxt) +{ + __kvm_hyp_host_forward_smc(host_ctxt); +} + +static void skip_host_instruction(void) +{ + write_sysreg_el2(read_sysreg_el2(SYS_ELR) + 4, SYS_ELR); +} + +static void handle_host_smc(struct kvm_cpu_context *host_ctxt) +{ + bool handled; + + handled = kvm_host_psci_handler(host_ctxt); + if (!handled) + default_host_smc_handler(host_ctxt); + + /* + * Unlike HVC, the return address of an SMC is the instruction's PC. + * Move the return address past the instruction. + */ + skip_host_instruction(); } void handle_trap(struct kvm_cpu_context *host_ctxt) { u64 esr = read_sysreg_el2(SYS_ESR); - unsigned long func_id; - if (ESR_ELx_EC(esr) != ESR_ELx_EC_HVC64) + switch (ESR_ELx_EC(esr)) { + case ESR_ELx_EC_HVC64: + handle_host_hcall(host_ctxt); + break; + case ESR_ELx_EC_SMC64: + handle_host_smc(host_ctxt); + break; + default: hyp_panic(); - - func_id = host_ctxt->regs.regs[0]; - handle_host_hcall(func_id, host_ctxt); + } } diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-smp.c b/arch/arm64/kvm/hyp/nvhe/hyp-smp.c new file mode 100644 index 000000000000..cbab0c6246e2 --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/hyp-smp.c @@ -0,0 +1,40 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 - Google LLC + * Author: David Brazdil <dbrazdil@google.com> + */ + +#include <asm/kvm_asm.h> +#include <asm/kvm_hyp.h> +#include <asm/kvm_mmu.h> + +/* + * nVHE copy of data structures tracking available CPU cores. + * Only entries for CPUs that were online at KVM init are populated. + * Other CPUs should not be allowed to boot because their features were + * not checked against the finalized system capabilities. + */ +u64 __ro_after_init __cpu_logical_map[NR_CPUS] = { [0 ... NR_CPUS-1] = INVALID_HWID }; + +u64 cpu_logical_map(unsigned int cpu) +{ + if (cpu >= ARRAY_SIZE(__cpu_logical_map)) + hyp_panic(); + + return __cpu_logical_map[cpu]; +} + +unsigned long __hyp_per_cpu_offset(unsigned int cpu) +{ + unsigned long *cpu_base_array; + unsigned long this_cpu_base; + unsigned long elf_base; + + if (cpu >= ARRAY_SIZE(kvm_arm_hyp_percpu_base)) + hyp_panic(); + + cpu_base_array = (unsigned long *)hyp_symbol_addr(kvm_arm_hyp_percpu_base); + this_cpu_base = kern_hyp_va(cpu_base_array[cpu]); + elf_base = (unsigned long)hyp_symbol_addr(__per_cpu_start); + return this_cpu_base - elf_base; +} diff --git a/arch/arm64/kvm/hyp/nvhe/hyp.lds.S b/arch/arm64/kvm/hyp/nvhe/hyp.lds.S index a797abace13f..1206d0d754d5 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp.lds.S +++ b/arch/arm64/kvm/hyp/nvhe/hyp.lds.S @@ -21,4 +21,5 @@ SECTIONS { HYP_SECTION_NAME(.data..percpu) : { PERCPU_INPUT(L1_CACHE_BYTES) } + HYP_SECTION(.data..ro_after_init) } diff --git a/arch/arm64/kvm/hyp/nvhe/psci-relay.c b/arch/arm64/kvm/hyp/nvhe/psci-relay.c new file mode 100644 index 000000000000..08dc9de69314 --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/psci-relay.c @@ -0,0 +1,324 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 - Google LLC + * Author: David Brazdil <dbrazdil@google.com> + */ + +#include <asm/kvm_asm.h> +#include <asm/kvm_hyp.h> +#include <asm/kvm_mmu.h> +#include <kvm/arm_hypercalls.h> +#include <linux/arm-smccc.h> +#include <linux/kvm_host.h> +#include <linux/psci.h> +#include <kvm/arm_psci.h> +#include <uapi/linux/psci.h> + +#include <nvhe/trap_handler.h> + +void kvm_hyp_cpu_entry(unsigned long r0); +void kvm_hyp_cpu_resume(unsigned long r0); + +void __noreturn __host_enter(struct kvm_cpu_context *host_ctxt); + +/* Config options set by the host. */ +__ro_after_init u32 kvm_host_psci_version; +__ro_after_init struct psci_0_1_function_ids kvm_host_psci_0_1_function_ids; +__ro_after_init s64 hyp_physvirt_offset; + +#define __hyp_pa(x) ((phys_addr_t)((x)) + hyp_physvirt_offset) + +#define INVALID_CPU_ID UINT_MAX + +struct psci_boot_args { + atomic_t lock; + unsigned long pc; + unsigned long r0; +}; + +#define PSCI_BOOT_ARGS_UNLOCKED 0 +#define PSCI_BOOT_ARGS_LOCKED 1 + +#define PSCI_BOOT_ARGS_INIT \ + ((struct psci_boot_args){ \ + .lock = ATOMIC_INIT(PSCI_BOOT_ARGS_UNLOCKED), \ + }) + +static DEFINE_PER_CPU(struct psci_boot_args, cpu_on_args) = PSCI_BOOT_ARGS_INIT; +static DEFINE_PER_CPU(struct psci_boot_args, suspend_args) = PSCI_BOOT_ARGS_INIT; + +static u64 get_psci_func_id(struct kvm_cpu_context *host_ctxt) +{ + DECLARE_REG(u64, func_id, host_ctxt, 0); + + return func_id; +} + +static bool is_psci_0_1_call(u64 func_id) +{ + return (func_id == kvm_host_psci_0_1_function_ids.cpu_suspend) || + (func_id == kvm_host_psci_0_1_function_ids.cpu_on) || + (func_id == kvm_host_psci_0_1_function_ids.cpu_off) || + (func_id == kvm_host_psci_0_1_function_ids.migrate); +} + +static bool is_psci_0_2_call(u64 func_id) +{ + /* SMCCC reserves IDs 0x00-1F with the given 32/64-bit base for PSCI. */ + return (PSCI_0_2_FN(0) <= func_id && func_id <= PSCI_0_2_FN(31)) || + (PSCI_0_2_FN64(0) <= func_id && func_id <= PSCI_0_2_FN64(31)); +} + +static bool is_psci_call(u64 func_id) +{ + switch (kvm_host_psci_version) { + case PSCI_VERSION(0, 1): + return is_psci_0_1_call(func_id); + default: + return is_psci_0_2_call(func_id); + } +} + +static unsigned long psci_call(unsigned long fn, unsigned long arg0, + unsigned long arg1, unsigned long arg2) +{ + struct arm_smccc_res res; + + arm_smccc_1_1_smc(fn, arg0, arg1, arg2, &res); + return res.a0; +} + +static unsigned long psci_forward(struct kvm_cpu_context *host_ctxt) +{ + return psci_call(cpu_reg(host_ctxt, 0), cpu_reg(host_ctxt, 1), + cpu_reg(host_ctxt, 2), cpu_reg(host_ctxt, 3)); +} + +static __noreturn unsigned long psci_forward_noreturn(struct kvm_cpu_context *host_ctxt) +{ + psci_forward(host_ctxt); + hyp_panic(); /* unreachable */ +} + +static unsigned int find_cpu_id(u64 mpidr) +{ + unsigned int i; + + /* Reject invalid MPIDRs */ + if (mpidr & ~MPIDR_HWID_BITMASK) + return INVALID_CPU_ID; + + for (i = 0; i < NR_CPUS; i++) { + if (cpu_logical_map(i) == mpidr) + return i; + } + + return INVALID_CPU_ID; +} + +static __always_inline bool try_acquire_boot_args(struct psci_boot_args *args) +{ + return atomic_cmpxchg_acquire(&args->lock, + PSCI_BOOT_ARGS_UNLOCKED, + PSCI_BOOT_ARGS_LOCKED) == + PSCI_BOOT_ARGS_UNLOCKED; +} + +static __always_inline void release_boot_args(struct psci_boot_args *args) +{ + atomic_set_release(&args->lock, PSCI_BOOT_ARGS_UNLOCKED); +} + +static int psci_cpu_on(u64 func_id, struct kvm_cpu_context *host_ctxt) +{ + DECLARE_REG(u64, mpidr, host_ctxt, 1); + DECLARE_REG(unsigned long, pc, host_ctxt, 2); + DECLARE_REG(unsigned long, r0, host_ctxt, 3); + + unsigned int cpu_id; + struct psci_boot_args *boot_args; + struct kvm_nvhe_init_params *init_params; + int ret; + + /* + * Find the logical CPU ID for the given MPIDR. The search set is + * the set of CPUs that were online at the point of KVM initialization. + * Booting other CPUs is rejected because their cpufeatures were not + * checked against the finalized capabilities. This could be relaxed + * by doing the feature checks in hyp. + */ + cpu_id = find_cpu_id(mpidr); + if (cpu_id == INVALID_CPU_ID) + return PSCI_RET_INVALID_PARAMS; + + boot_args = per_cpu_ptr(hyp_symbol_addr(cpu_on_args), cpu_id); + init_params = per_cpu_ptr(hyp_symbol_addr(kvm_init_params), cpu_id); + + /* Check if the target CPU is already being booted. */ + if (!try_acquire_boot_args(boot_args)) + return PSCI_RET_ALREADY_ON; + + boot_args->pc = pc; + boot_args->r0 = r0; + wmb(); + + ret = psci_call(func_id, mpidr, + __hyp_pa(hyp_symbol_addr(kvm_hyp_cpu_entry)), + __hyp_pa(init_params)); + + /* If successful, the lock will be released by the target CPU. */ + if (ret != PSCI_RET_SUCCESS) + release_boot_args(boot_args); + + return ret; +} + +static int psci_cpu_suspend(u64 func_id, struct kvm_cpu_context *host_ctxt) +{ + DECLARE_REG(u64, power_state, host_ctxt, 1); + DECLARE_REG(unsigned long, pc, host_ctxt, 2); + DECLARE_REG(unsigned long, r0, host_ctxt, 3); + + struct psci_boot_args *boot_args; + struct kvm_nvhe_init_params *init_params; + + boot_args = this_cpu_ptr(hyp_symbol_addr(suspend_args)); + init_params = this_cpu_ptr(hyp_symbol_addr(kvm_init_params)); + + /* + * No need to acquire a lock before writing to boot_args because a core + * can only suspend itself. Racy CPU_ON calls use a separate struct. + */ + boot_args->pc = pc; + boot_args->r0 = r0; + + /* + * Will either return if shallow sleep state, or wake up into the entry + * point if it is a deep sleep state. + */ + return psci_call(func_id, power_state, + __hyp_pa(hyp_symbol_addr(kvm_hyp_cpu_resume)), + __hyp_pa(init_params)); +} + +static int psci_system_suspend(u64 func_id, struct kvm_cpu_context *host_ctxt) +{ + DECLARE_REG(unsigned long, pc, host_ctxt, 1); + DECLARE_REG(unsigned long, r0, host_ctxt, 2); + + struct psci_boot_args *boot_args; + struct kvm_nvhe_init_params *init_params; + + boot_args = this_cpu_ptr(hyp_symbol_addr(suspend_args)); + init_params = this_cpu_ptr(hyp_symbol_addr(kvm_init_params)); + + /* + * No need to acquire a lock before writing to boot_args because a core + * can only suspend itself. Racy CPU_ON calls use a separate struct. + */ + boot_args->pc = pc; + boot_args->r0 = r0; + + /* Will only return on error. */ + return psci_call(func_id, + __hyp_pa(hyp_symbol_addr(kvm_hyp_cpu_resume)), + __hyp_pa(init_params), 0); +} + +asmlinkage void __noreturn kvm_host_psci_cpu_entry(bool is_cpu_on) +{ + struct psci_boot_args *boot_args; + struct kvm_cpu_context *host_ctxt; + + host_ctxt = &this_cpu_ptr(hyp_symbol_addr(kvm_host_data))->host_ctxt; + + if (is_cpu_on) + boot_args = this_cpu_ptr(hyp_symbol_addr(cpu_on_args)); + else + boot_args = this_cpu_ptr(hyp_symbol_addr(suspend_args)); + + cpu_reg(host_ctxt, 0) = boot_args->r0; + write_sysreg_el2(boot_args->pc, SYS_ELR); + + if (is_cpu_on) + release_boot_args(boot_args); + + __host_enter(host_ctxt); +} + +static unsigned long psci_0_1_handler(u64 func_id, struct kvm_cpu_context *host_ctxt) +{ + if ((func_id == kvm_host_psci_0_1_function_ids.cpu_off) || + (func_id == kvm_host_psci_0_1_function_ids.migrate)) + return psci_forward(host_ctxt); + else if (func_id == kvm_host_psci_0_1_function_ids.cpu_on) + return psci_cpu_on(func_id, host_ctxt); + else if (func_id == kvm_host_psci_0_1_function_ids.cpu_suspend) + return psci_cpu_suspend(func_id, host_ctxt); + else + return PSCI_RET_NOT_SUPPORTED; +} + +static unsigned long psci_0_2_handler(u64 func_id, struct kvm_cpu_context *host_ctxt) +{ + switch (func_id) { + case PSCI_0_2_FN_PSCI_VERSION: + case PSCI_0_2_FN_CPU_OFF: + case PSCI_0_2_FN64_AFFINITY_INFO: + case PSCI_0_2_FN64_MIGRATE: + case PSCI_0_2_FN_MIGRATE_INFO_TYPE: + case PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU: + return psci_forward(host_ctxt); + case PSCI_0_2_FN_SYSTEM_OFF: + case PSCI_0_2_FN_SYSTEM_RESET: + psci_forward_noreturn(host_ctxt); + unreachable(); + case PSCI_0_2_FN64_CPU_SUSPEND: + return psci_cpu_suspend(func_id, host_ctxt); + case PSCI_0_2_FN64_CPU_ON: + return psci_cpu_on(func_id, host_ctxt); + default: + return PSCI_RET_NOT_SUPPORTED; + } +} + +static unsigned long psci_1_0_handler(u64 func_id, struct kvm_cpu_context *host_ctxt) +{ + switch (func_id) { + case PSCI_1_0_FN_PSCI_FEATURES: + case PSCI_1_0_FN_SET_SUSPEND_MODE: + case PSCI_1_1_FN64_SYSTEM_RESET2: + return psci_forward(host_ctxt); + case PSCI_1_0_FN64_SYSTEM_SUSPEND: + return psci_system_suspend(func_id, host_ctxt); + default: + return psci_0_2_handler(func_id, host_ctxt); + } +} + +bool kvm_host_psci_handler(struct kvm_cpu_context *host_ctxt) +{ + u64 func_id = get_psci_func_id(host_ctxt); + unsigned long ret; + + if (!is_psci_call(func_id)) + return false; + + switch (kvm_host_psci_version) { + case PSCI_VERSION(0, 1): + ret = psci_0_1_handler(func_id, host_ctxt); + break; + case PSCI_VERSION(0, 2): + ret = psci_0_2_handler(func_id, host_ctxt); + break; + default: + ret = psci_1_0_handler(func_id, host_ctxt); + break; + } + + cpu_reg(host_ctxt, 0) = ret; + cpu_reg(host_ctxt, 1) = 0; + cpu_reg(host_ctxt, 2) = 0; + cpu_reg(host_ctxt, 3) = 0; + return true; +} diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c index 8ae8160bc93a..f3d0e9eca56c 100644 --- a/arch/arm64/kvm/hyp/nvhe/switch.c +++ b/arch/arm64/kvm/hyp/nvhe/switch.c @@ -4,6 +4,7 @@ * Author: Marc Zyngier <marc.zyngier@arm.com> */ +#include <hyp/adjust_pc.h> #include <hyp/switch.h> #include <hyp/sysreg-sr.h> @@ -96,7 +97,10 @@ static void __deactivate_traps(struct kvm_vcpu *vcpu) mdcr_el2 |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT; write_sysreg(mdcr_el2, mdcr_el2); - write_sysreg(HCR_HOST_NVHE_FLAGS, hcr_el2); + if (is_protected_kvm_enabled()) + write_sysreg(HCR_HOST_NVHE_PROTECTED_FLAGS, hcr_el2); + else + write_sysreg(HCR_HOST_NVHE_FLAGS, hcr_el2); write_sysreg(CPTR_EL2_DEFAULT, cptr_el2); write_sysreg(__kvm_hyp_host_vector, vbar_el2); } @@ -189,6 +193,8 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu) __sysreg_save_state_nvhe(host_ctxt); + __adjust_pc(vcpu); + /* * We must restore the 32-bit state before the sysregs, thanks * to erratum #852523 (Cortex-A57) or #853709 (Cortex-A72). diff --git a/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c b/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c index 88a25fc8fcd3..29305022bc04 100644 --- a/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c +++ b/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c @@ -33,14 +33,3 @@ void __sysreg_restore_state_nvhe(struct kvm_cpu_context *ctxt) __sysreg_restore_user_state(ctxt); __sysreg_restore_el2_return_state(ctxt); } - -void __kvm_enable_ssbs(void) -{ - u64 tmp; - - asm volatile( - "mrs %0, sctlr_el2\n" - "orr %0, %0, %1\n" - "msr sctlr_el2, %0" - : "=&r" (tmp) : "L" (SCTLR_ELx_DSSBS)); -} diff --git a/arch/arm64/kvm/hyp/smccc_wa.S b/arch/arm64/kvm/hyp/smccc_wa.S deleted file mode 100644 index b0441dbdf68b..000000000000 --- a/arch/arm64/kvm/hyp/smccc_wa.S +++ /dev/null @@ -1,32 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-only */ -/* - * Copyright (C) 2015-2018 - ARM Ltd - * Author: Marc Zyngier <marc.zyngier@arm.com> - */ - -#include <linux/arm-smccc.h> -#include <linux/linkage.h> - -#include <asm/kvm_asm.h> -#include <asm/kvm_mmu.h> - - /* - * This is not executed directly and is instead copied into the vectors - * by install_bp_hardening_cb(). - */ - .data - .pushsection .rodata - .global __smccc_workaround_1_smc -SYM_DATA_START(__smccc_workaround_1_smc) - esb - sub sp, sp, #(8 * 4) - stp x2, x3, [sp, #(8 * 0)] - stp x0, x1, [sp, #(8 * 2)] - mov w0, #ARM_SMCCC_ARCH_WORKAROUND_1 - smc #0 - ldp x2, x3, [sp, #(8 * 0)] - ldp x0, x1, [sp, #(8 * 2)] - add sp, sp, #(8 * 4) -1: .org __smccc_workaround_1_smc + __SMCCC_WORKAROUND_1_SMC_SZ - .org 1b -SYM_DATA_END(__smccc_workaround_1_smc) diff --git a/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c b/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c index bd1bab551d48..8f0585640241 100644 --- a/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c +++ b/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c @@ -4,6 +4,8 @@ * Author: Marc Zyngier <marc.zyngier@arm.com> */ +#include <hyp/adjust_pc.h> + #include <linux/compiler.h> #include <linux/irqchip/arm-gic.h> #include <linux/kvm_host.h> diff --git a/arch/arm64/kvm/hyp/vgic-v3-sr.c b/arch/arm64/kvm/hyp/vgic-v3-sr.c index 452f4cacd674..80406f463c28 100644 --- a/arch/arm64/kvm/hyp/vgic-v3-sr.c +++ b/arch/arm64/kvm/hyp/vgic-v3-sr.c @@ -4,6 +4,8 @@ * Author: Marc Zyngier <marc.zyngier@arm.com> */ +#include <hyp/adjust_pc.h> + #include <linux/compiler.h> #include <linux/irqchip/arm-gic-v3.h> #include <linux/kvm_host.h> diff --git a/arch/arm64/kvm/hyp/vhe/Makefile b/arch/arm64/kvm/hyp/vhe/Makefile index 461e97c375cc..96bec0ecf9dd 100644 --- a/arch/arm64/kvm/hyp/vhe/Makefile +++ b/arch/arm64/kvm/hyp/vhe/Makefile @@ -8,4 +8,4 @@ ccflags-y := -D__KVM_VHE_HYPERVISOR__ obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \ - ../fpsimd.o ../hyp-entry.o + ../fpsimd.o ../hyp-entry.o ../exception.o diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c index 62546e20b251..af8e940d0f03 100644 --- a/arch/arm64/kvm/hyp/vhe/switch.c +++ b/arch/arm64/kvm/hyp/vhe/switch.c @@ -4,6 +4,7 @@ * Author: Marc Zyngier <marc.zyngier@arm.com> */ +#include <hyp/adjust_pc.h> #include <hyp/switch.h> #include <linux/arm-smccc.h> @@ -133,6 +134,8 @@ static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) __load_guest_stage2(vcpu->arch.hw_mmu); __activate_traps(vcpu); + __adjust_pc(vcpu); + sysreg_restore_guest_state_vhe(guest_ctxt); __debug_switch_to_guest(vcpu); |