diff options
author | Marc Zyngier <maz@kernel.org> | 2020-11-27 11:33:10 +0000 |
---|---|---|
committer | Marc Zyngier <maz@kernel.org> | 2020-11-27 11:33:10 +0000 |
commit | 37da329ed6a7fd7d5c874ff99b9fc3a18e9c7c64 (patch) | |
tree | d7344c4c6c98338998e31f3f2a2017f615e886bf /arch/arm64/kvm | |
parent | 09162bc32c880a791c6c0668ce0745cf7958f576 (diff) | |
parent | 90c1f934ed7141a6d4c202936d12faaeb405fb66 (diff) |
Merge branch 'kvm-arm64/el2-pc' into kvmarm-master/next
Signed-off-by: Marc Zyngier <maz@kernel.org>
Diffstat (limited to 'arch/arm64/kvm')
-rw-r--r-- | arch/arm64/kvm/Makefile | 4 | ||||
-rw-r--r-- | arch/arm64/kvm/aarch32.c | 232 | ||||
-rw-r--r-- | arch/arm64/kvm/guest.c | 28 | ||||
-rw-r--r-- | arch/arm64/kvm/handle_exit.c | 23 | ||||
-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/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/nvhe/Makefile | 2 | ||||
-rw-r--r-- | arch/arm64/kvm/hyp/nvhe/switch.c | 3 | ||||
-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 | ||||
-rw-r--r-- | arch/arm64/kvm/inject_fault.c | 189 | ||||
-rw-r--r-- | arch/arm64/kvm/mmio.c | 2 | ||||
-rw-r--r-- | arch/arm64/kvm/mmu.c | 2 | ||||
-rw-r--r-- | arch/arm64/kvm/regmap.c | 224 | ||||
-rw-r--r-- | arch/arm64/kvm/sys_regs.c | 83 |
19 files changed, 535 insertions, 680 deletions
diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 1504c81fbf5d..60fd181df624 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -13,10 +13,10 @@ obj-$(CONFIG_KVM) += hyp/ kvm-y := $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o \ $(KVM)/vfio.o $(KVM)/irqchip.o \ arm.o mmu.o mmio.o psci.o perf.o hypercalls.o pvtime.o \ - inject_fault.o regmap.o va_layout.o handle_exit.o \ + inject_fault.o va_layout.o handle_exit.o \ guest.o debug.o reset.o sys_regs.o \ vgic-sys-reg-v3.o fpsimd.o pmu.o \ - aarch32.o arch_timer.o \ + arch_timer.o \ vgic/vgic.o vgic/vgic-init.o \ vgic/vgic-irqfd.o vgic/vgic-v2.o \ vgic/vgic-v3.o vgic/vgic-v4.o \ diff --git a/arch/arm64/kvm/aarch32.c b/arch/arm64/kvm/aarch32.c deleted file mode 100644 index 40a62a99fbf8..000000000000 --- a/arch/arm64/kvm/aarch32.c +++ /dev/null @@ -1,232 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * (not much of an) Emulation layer for 32bit 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 <linux/bits.h> -#include <linux/kvm_host.h> -#include <asm/kvm_emulate.h> -#include <asm/kvm_hyp.h> - -#define DFSR_FSC_EXTABT_LPAE 0x10 -#define DFSR_FSC_EXTABT_nLPAE 0x08 -#define DFSR_LPAE BIT(9) - -/* - * 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 bool pre_fault_synchronize(struct kvm_vcpu *vcpu) -{ - preempt_disable(); - if (vcpu->arch.sysregs_loaded_on_cpu) { - kvm_arch_vcpu_put(vcpu); - return true; - } - - preempt_enable(); - return false; -} - -static void post_fault_synchronize(struct kvm_vcpu *vcpu, bool loaded) -{ - if (loaded) { - kvm_arch_vcpu_load(vcpu, smp_processor_id()); - preempt_enable(); - } -} - -/* - * 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_cp15(vcpu, c1_SCTLR); - 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; -} - -static void prepare_fault32(struct kvm_vcpu *vcpu, u32 mode, u32 vect_offset) -{ - unsigned long spsr = *vcpu_cpsr(vcpu); - bool is_thumb = (spsr & PSR_AA32_T_BIT); - u32 return_offset = return_offsets[vect_offset >> 2][is_thumb]; - u32 sctlr = vcpu_cp15(vcpu, c1_SCTLR); - - *vcpu_cpsr(vcpu) = get_except32_cpsr(vcpu, mode); - - /* Note: These now point to the banked copies */ - vcpu_write_spsr(vcpu, host_spsr_to_spsr32(spsr)); - *vcpu_reg32(vcpu, 14) = *vcpu_pc(vcpu) + return_offset; - - /* Branch to exception vector */ - if (sctlr & (1 << 13)) - vect_offset += 0xffff0000; - else /* always have security exceptions */ - vect_offset += vcpu_cp15(vcpu, c12_VBAR); - - *vcpu_pc(vcpu) = vect_offset; -} - -void kvm_inject_undef32(struct kvm_vcpu *vcpu) -{ - bool loaded = pre_fault_synchronize(vcpu); - - prepare_fault32(vcpu, PSR_AA32_MODE_UND, 4); - post_fault_synchronize(vcpu, loaded); -} - -/* - * Modelled after TakeDataAbortException() and TakePrefetchAbortException - * pseudocode. - */ -static void inject_abt32(struct kvm_vcpu *vcpu, bool is_pabt, - unsigned long addr) -{ - u32 vect_offset; - u32 *far, *fsr; - bool is_lpae; - bool loaded; - - loaded = pre_fault_synchronize(vcpu); - - if (is_pabt) { - vect_offset = 12; - far = &vcpu_cp15(vcpu, c6_IFAR); - fsr = &vcpu_cp15(vcpu, c5_IFSR); - } else { /* !iabt */ - vect_offset = 16; - far = &vcpu_cp15(vcpu, c6_DFAR); - fsr = &vcpu_cp15(vcpu, c5_DFSR); - } - - prepare_fault32(vcpu, PSR_AA32_MODE_ABT, vect_offset); - - *far = addr; - - /* Give the guest an IMPLEMENTATION DEFINED exception */ - is_lpae = (vcpu_cp15(vcpu, c2_TTBCR) >> 31); - if (is_lpae) { - *fsr = DFSR_LPAE | DFSR_FSC_EXTABT_LPAE; - } else { - /* no need to shuffle FS[4] into DFSR[10] as its 0 */ - *fsr = DFSR_FSC_EXTABT_nLPAE; - } - - post_fault_synchronize(vcpu, loaded); -} - -void kvm_inject_dabt32(struct kvm_vcpu *vcpu, unsigned long addr) -{ - inject_abt32(vcpu, false, addr); -} - -void kvm_inject_pabt32(struct kvm_vcpu *vcpu, unsigned long addr) -{ - inject_abt32(vcpu, true, addr); -} diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index dfb5218137ca..3f23f7478d2a 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -252,10 +252,32 @@ static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) memcpy(addr, valp, KVM_REG_SIZE(reg->id)); if (*vcpu_cpsr(vcpu) & PSR_MODE32_BIT) { - int i; + int i, nr_reg; + + switch (*vcpu_cpsr(vcpu)) { + /* + * Either we are dealing with user mode, and only the + * first 15 registers (+ PC) must be narrowed to 32bit. + * AArch32 r0-r14 conveniently map to AArch64 x0-x14. + */ + case PSR_AA32_MODE_USR: + case PSR_AA32_MODE_SYS: + nr_reg = 15; + break; + + /* + * Otherwide, this is a priviledged mode, and *all* the + * registers must be narrowed to 32bit. + */ + default: + nr_reg = 31; + break; + } + + for (i = 0; i < nr_reg; i++) + vcpu_set_reg(vcpu, i, (u32)vcpu_get_reg(vcpu, i)); - for (i = 0; i < 16; i++) - *vcpu_reg32(vcpu, i) = (u32)*vcpu_reg32(vcpu, i); + *vcpu_pc(vcpu) = (u32)*vcpu_pc(vcpu); } out: return err; diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index 5d690d60ccad..f79137ee4274 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -61,7 +61,7 @@ static int handle_smc(struct kvm_vcpu *vcpu) * otherwise return to the same address... */ vcpu_set_reg(vcpu, 0, ~0UL); - kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu)); + kvm_incr_pc(vcpu); return 1; } @@ -100,7 +100,7 @@ static int kvm_handle_wfx(struct kvm_vcpu *vcpu) kvm_clear_request(KVM_REQ_UNHALT, vcpu); } - kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu)); + kvm_incr_pc(vcpu); return 1; } @@ -221,7 +221,7 @@ static int handle_trap_exceptions(struct kvm_vcpu *vcpu) * that fail their condition code check" */ if (!kvm_condition_valid(vcpu)) { - kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu)); + kvm_incr_pc(vcpu); handled = 1; } else { exit_handle_fn exit_handler; @@ -241,23 +241,6 @@ int handle_exit(struct kvm_vcpu *vcpu, int exception_index) { struct kvm_run *run = vcpu->run; - if (ARM_SERROR_PENDING(exception_index)) { - u8 esr_ec = ESR_ELx_EC(kvm_vcpu_get_esr(vcpu)); - - /* - * HVC/SMC already have an adjusted PC, which we need - * to correct in order to return to after having - * injected the SError. - */ - if (esr_ec == ESR_ELx_EC_HVC32 || esr_ec == ESR_ELx_EC_HVC64 || - esr_ec == ESR_ELx_EC_SMC32 || esr_ec == ESR_ELx_EC_SMC64) { - u32 adj = kvm_vcpu_trap_il_is32bit(vcpu) ? 4 : 2; - *vcpu_pc(vcpu) -= adj; - } - - return 1; - } - exception_index = ARM_EXCEPTION_CODE(exception_index); switch (exception_index) { 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/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/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index ddde15fe85f2..77b8c4e06f2f 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -8,7 +8,7 @@ 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 += ../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/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c index 8ae8160bc93a..3e50ff35aa4f 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> @@ -189,6 +190,8 @@ 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/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); diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c index 34a96ab244fa..e2a2e48ca371 100644 --- a/arch/arm64/kvm/inject_fault.c +++ b/arch/arm64/kvm/inject_fault.c @@ -14,119 +14,15 @@ #include <asm/kvm_emulate.h> #include <asm/esr.h> -#define CURRENT_EL_SP_EL0_VECTOR 0x0 -#define CURRENT_EL_SP_ELx_VECTOR 0x200 -#define LOWER_EL_AArch64_VECTOR 0x400 -#define LOWER_EL_AArch32_VECTOR 0x600 - -enum exception_type { - except_type_sync = 0, - except_type_irq = 0x80, - except_type_fiq = 0x100, - except_type_serror = 0x180, -}; - -/* - * 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. |