From: David Brazdil Date: Thu, 25 Jun 2020 13:14:16 +0000 (+0100) Subject: KVM: arm64: Split hyp/sysreg-sr.c to VHE/nVHE X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=13aeb9b400c5d7c5e979fdbbf994c787487f7889;p=linux.git KVM: arm64: Split hyp/sysreg-sr.c to VHE/nVHE sysreg-sr.c contains KVM's code for saving/restoring system registers, with some code shared between VHE/nVHE. These common routines are moved to a header file, VHE-specific code is moved to vhe/sysreg-sr.c and nVHE-specific code to nvhe/sysreg-sr.c. Signed-off-by: David Brazdil Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20200625131420.71444-12-dbrazdil@google.com --- diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 49d1a5cd8f8f4..e0920df1d0c14 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -338,7 +338,7 @@ struct kvm_vcpu_arch { struct vcpu_reset_state reset_state; /* True when deferrable sysregs are loaded on the physical CPU, - * see kvm_vcpu_load_sysregs and kvm_vcpu_put_sysregs. */ + * see kvm_vcpu_load_sysregs_vhe and kvm_vcpu_put_sysregs_vhe. */ bool sysregs_loaded_on_cpu; /* Guest PV state */ @@ -639,8 +639,8 @@ static inline int kvm_arm_have_ssbd(void) } } -void kvm_vcpu_load_sysregs(struct kvm_vcpu *vcpu); -void kvm_vcpu_put_sysregs(struct kvm_vcpu *vcpu); +void kvm_vcpu_load_sysregs_vhe(struct kvm_vcpu *vcpu); +void kvm_vcpu_put_sysregs_vhe(struct kvm_vcpu *vcpu); int kvm_set_ipa_limit(void); diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h index 82fa05d15b8bd..997c5bda1ac79 100644 --- a/arch/arm64/include/asm/kvm_hyp.h +++ b/arch/arm64/include/asm/kvm_hyp.h @@ -66,14 +66,15 @@ int __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu); void __timer_enable_traps(struct kvm_vcpu *vcpu); void __timer_disable_traps(struct kvm_vcpu *vcpu); +#ifdef __KVM_NVHE_HYPERVISOR__ void __sysreg_save_state_nvhe(struct kvm_cpu_context *ctxt); void __sysreg_restore_state_nvhe(struct kvm_cpu_context *ctxt); +#else void sysreg_save_host_state_vhe(struct kvm_cpu_context *ctxt); void sysreg_restore_host_state_vhe(struct kvm_cpu_context *ctxt); void sysreg_save_guest_state_vhe(struct kvm_cpu_context *ctxt); void sysreg_restore_guest_state_vhe(struct kvm_cpu_context *ctxt); -void __sysreg32_save_state(struct kvm_vcpu *vcpu); -void __sysreg32_restore_state(struct kvm_vcpu *vcpu); +#endif void __debug_switch_to_guest(struct kvm_vcpu *vcpu); void __debug_switch_to_host(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h index c44ca4e7dd663..59eb55893eaf6 100644 --- a/arch/arm64/kernel/image-vars.h +++ b/arch/arm64/kernel/image-vars.h @@ -76,13 +76,6 @@ KVM_NVHE_ALIAS(abort_guest_exit_start); KVM_NVHE_ALIAS(__fpsimd_restore_state); KVM_NVHE_ALIAS(__fpsimd_save_state); -/* Symbols defined in sysreg-sr.c (not yet compiled with nVHE build rules). */ -KVM_NVHE_ALIAS(__kvm_enable_ssbs); -KVM_NVHE_ALIAS(__sysreg32_restore_state); -KVM_NVHE_ALIAS(__sysreg32_save_state); -KVM_NVHE_ALIAS(__sysreg_restore_state_nvhe); -KVM_NVHE_ALIAS(__sysreg_save_state_nvhe); - /* Symbols defined in timer-sr.c (not yet compiled with nVHE build rules). */ KVM_NVHE_ALIAS(__kvm_timer_set_cntvoff); KVM_NVHE_ALIAS(__timer_disable_traps); diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 26780b78a523f..0bf2cf5614c6b 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -351,7 +351,8 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) kvm_vgic_load(vcpu); kvm_timer_vcpu_load(vcpu); - kvm_vcpu_load_sysregs(vcpu); + if (has_vhe()) + kvm_vcpu_load_sysregs_vhe(vcpu); kvm_arch_vcpu_load_fp(vcpu); kvm_vcpu_pmu_restore_guest(vcpu); if (kvm_arm_is_pvtime_enabled(&vcpu->arch)) @@ -369,7 +370,8 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) { kvm_arch_vcpu_put_fp(vcpu); - kvm_vcpu_put_sysregs(vcpu); + if (has_vhe()) + kvm_vcpu_put_sysregs_vhe(vcpu); kvm_timer_vcpu_put(vcpu); kvm_vgic_put(vcpu); kvm_vcpu_pmu_restore_host(vcpu); @@ -1302,7 +1304,7 @@ static void cpu_init_hyp_mode(void) */ if (this_cpu_has_cap(ARM64_SSBS) && arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE) { - kvm_call_hyp(__kvm_enable_ssbs); + kvm_call_hyp_nvhe(__kvm_enable_ssbs); } } diff --git a/arch/arm64/kvm/hyp/Makefile b/arch/arm64/kvm/hyp/Makefile index fc09025d2e97d..f497972378183 100644 --- a/arch/arm64/kvm/hyp/Makefile +++ b/arch/arm64/kvm/hyp/Makefile @@ -13,8 +13,8 @@ subdir-ccflags-y := -I$(incdir) \ obj-$(CONFIG_KVM) += hyp.o vhe/ nvhe/ obj-$(CONFIG_KVM_INDIRECT_VECTORS) += smccc_wa.o -hyp-y := vgic-v3-sr.o timer-sr.o aarch32.o vgic-v2-cpuif-proxy.o sysreg-sr.o \ - entry.o fpsimd.o +hyp-y := vgic-v3-sr.o timer-sr.o aarch32.o vgic-v2-cpuif-proxy.o entry.o \ + fpsimd.o # KVM code is run at a different exception code with a different map, so # compiler instrumentation that inserts callbacks or checks into the code may diff --git a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h new file mode 100644 index 0000000000000..3e0585fbd4032 --- /dev/null +++ b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h @@ -0,0 +1,203 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012-2015 - ARM Ltd + * Author: Marc Zyngier + */ + +#ifndef __ARM64_KVM_HYP_SYSREG_SR_H__ +#define __ARM64_KVM_HYP_SYSREG_SR_H__ + +#include +#include + +#include +#include +#include +#include + +static inline void __hyp_text __sysreg_save_common_state(struct kvm_cpu_context *ctxt) +{ + ctxt->sys_regs[MDSCR_EL1] = read_sysreg(mdscr_el1); +} + +static inline void __hyp_text __sysreg_save_user_state(struct kvm_cpu_context *ctxt) +{ + ctxt->sys_regs[TPIDR_EL0] = read_sysreg(tpidr_el0); + ctxt->sys_regs[TPIDRRO_EL0] = read_sysreg(tpidrro_el0); +} + +static inline void __hyp_text __sysreg_save_el1_state(struct kvm_cpu_context *ctxt) +{ + ctxt->sys_regs[CSSELR_EL1] = read_sysreg(csselr_el1); + ctxt->sys_regs[SCTLR_EL1] = read_sysreg_el1(SYS_SCTLR); + ctxt->sys_regs[CPACR_EL1] = read_sysreg_el1(SYS_CPACR); + ctxt->sys_regs[TTBR0_EL1] = read_sysreg_el1(SYS_TTBR0); + ctxt->sys_regs[TTBR1_EL1] = read_sysreg_el1(SYS_TTBR1); + ctxt->sys_regs[TCR_EL1] = read_sysreg_el1(SYS_TCR); + ctxt->sys_regs[ESR_EL1] = read_sysreg_el1(SYS_ESR); + ctxt->sys_regs[AFSR0_EL1] = read_sysreg_el1(SYS_AFSR0); + ctxt->sys_regs[AFSR1_EL1] = read_sysreg_el1(SYS_AFSR1); + ctxt->sys_regs[FAR_EL1] = read_sysreg_el1(SYS_FAR); + ctxt->sys_regs[MAIR_EL1] = read_sysreg_el1(SYS_MAIR); + ctxt->sys_regs[VBAR_EL1] = read_sysreg_el1(SYS_VBAR); + ctxt->sys_regs[CONTEXTIDR_EL1] = read_sysreg_el1(SYS_CONTEXTIDR); + ctxt->sys_regs[AMAIR_EL1] = read_sysreg_el1(SYS_AMAIR); + ctxt->sys_regs[CNTKCTL_EL1] = read_sysreg_el1(SYS_CNTKCTL); + ctxt->sys_regs[PAR_EL1] = read_sysreg(par_el1); + ctxt->sys_regs[TPIDR_EL1] = read_sysreg(tpidr_el1); + + ctxt->gp_regs.sp_el1 = read_sysreg(sp_el1); + ctxt->gp_regs.elr_el1 = read_sysreg_el1(SYS_ELR); + ctxt->gp_regs.spsr[KVM_SPSR_EL1]= read_sysreg_el1(SYS_SPSR); +} + +static inline void __hyp_text __sysreg_save_el2_return_state(struct kvm_cpu_context *ctxt) +{ + ctxt->gp_regs.regs.pc = read_sysreg_el2(SYS_ELR); + ctxt->gp_regs.regs.pstate = read_sysreg_el2(SYS_SPSR); + + if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN)) + ctxt->sys_regs[DISR_EL1] = read_sysreg_s(SYS_VDISR_EL2); +} + +static inline void __hyp_text __sysreg_restore_common_state(struct kvm_cpu_context *ctxt) +{ + write_sysreg(ctxt->sys_regs[MDSCR_EL1], mdscr_el1); +} + +static inline void __hyp_text __sysreg_restore_user_state(struct kvm_cpu_context *ctxt) +{ + write_sysreg(ctxt->sys_regs[TPIDR_EL0], tpidr_el0); + write_sysreg(ctxt->sys_regs[TPIDRRO_EL0], tpidrro_el0); +} + +static inline void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt) +{ + write_sysreg(ctxt->sys_regs[MPIDR_EL1], vmpidr_el2); + write_sysreg(ctxt->sys_regs[CSSELR_EL1], csselr_el1); + + if (has_vhe() || + !cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { + write_sysreg_el1(ctxt->sys_regs[SCTLR_EL1], SYS_SCTLR); + write_sysreg_el1(ctxt->sys_regs[TCR_EL1], SYS_TCR); + } else if (!ctxt->__hyp_running_vcpu) { + /* + * Must only be done for guest registers, hence the context + * test. We're coming from the host, so SCTLR.M is already + * set. Pairs with nVHE's __activate_traps(). + */ + write_sysreg_el1((ctxt->sys_regs[TCR_EL1] | + TCR_EPD1_MASK | TCR_EPD0_MASK), + SYS_TCR); + isb(); + } + + write_sysreg_el1(ctxt->sys_regs[CPACR_EL1], SYS_CPACR); + write_sysreg_el1(ctxt->sys_regs[TTBR0_EL1], SYS_TTBR0); + write_sysreg_el1(ctxt->sys_regs[TTBR1_EL1], SYS_TTBR1); + write_sysreg_el1(ctxt->sys_regs[ESR_EL1], SYS_ESR); + write_sysreg_el1(ctxt->sys_regs[AFSR0_EL1], SYS_AFSR0); + write_sysreg_el1(ctxt->sys_regs[AFSR1_EL1], SYS_AFSR1); + write_sysreg_el1(ctxt->sys_regs[FAR_EL1], SYS_FAR); + write_sysreg_el1(ctxt->sys_regs[MAIR_EL1], SYS_MAIR); + write_sysreg_el1(ctxt->sys_regs[VBAR_EL1], SYS_VBAR); + write_sysreg_el1(ctxt->sys_regs[CONTEXTIDR_EL1],SYS_CONTEXTIDR); + write_sysreg_el1(ctxt->sys_regs[AMAIR_EL1], SYS_AMAIR); + write_sysreg_el1(ctxt->sys_regs[CNTKCTL_EL1], SYS_CNTKCTL); + write_sysreg(ctxt->sys_regs[PAR_EL1], par_el1); + write_sysreg(ctxt->sys_regs[TPIDR_EL1], tpidr_el1); + + if (!has_vhe() && + cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT) && + ctxt->__hyp_running_vcpu) { + /* + * Must only be done for host registers, hence the context + * test. Pairs with nVHE's __deactivate_traps(). + */ + isb(); + /* + * At this stage, and thanks to the above isb(), S2 is + * deconfigured and disabled. We can now restore the host's + * S1 configuration: SCTLR, and only then TCR. + */ + write_sysreg_el1(ctxt->sys_regs[SCTLR_EL1], SYS_SCTLR); + isb(); + write_sysreg_el1(ctxt->sys_regs[TCR_EL1], SYS_TCR); + } + + write_sysreg(ctxt->gp_regs.sp_el1, sp_el1); + write_sysreg_el1(ctxt->gp_regs.elr_el1, SYS_ELR); + write_sysreg_el1(ctxt->gp_regs.spsr[KVM_SPSR_EL1],SYS_SPSR); +} + +static inline void __hyp_text __sysreg_restore_el2_return_state(struct kvm_cpu_context *ctxt) +{ + u64 pstate = ctxt->gp_regs.regs.pstate; + u64 mode = pstate & PSR_AA32_MODE_MASK; + + /* + * Safety check to ensure we're setting the CPU up to enter the guest + * in a less privileged mode. + * + * If we are attempting a return to EL2 or higher in AArch64 state, + * program SPSR_EL2 with M=EL2h and the IL bit set which ensures that + * we'll take an illegal exception state exception immediately after + * the ERET to the guest. Attempts to return to AArch32 Hyp will + * result in an illegal exception return because EL2's execution state + * is determined by SCR_EL3.RW. + */ + if (!(mode & PSR_MODE32_BIT) && mode >= PSR_MODE_EL2t) + pstate = PSR_MODE_EL2h | PSR_IL_BIT; + + write_sysreg_el2(ctxt->gp_regs.regs.pc, SYS_ELR); + write_sysreg_el2(pstate, SYS_SPSR); + + if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN)) + write_sysreg_s(ctxt->sys_regs[DISR_EL1], SYS_VDISR_EL2); +} + +static inline void __hyp_text __sysreg32_save_state(struct kvm_vcpu *vcpu) +{ + u64 *spsr, *sysreg; + + if (!vcpu_el1_is_32bit(vcpu)) + return; + + spsr = vcpu->arch.ctxt.gp_regs.spsr; + sysreg = vcpu->arch.ctxt.sys_regs; + + spsr[KVM_SPSR_ABT] = read_sysreg(spsr_abt); + spsr[KVM_SPSR_UND] = read_sysreg(spsr_und); + spsr[KVM_SPSR_IRQ] = read_sysreg(spsr_irq); + spsr[KVM_SPSR_FIQ] = read_sysreg(spsr_fiq); + + sysreg[DACR32_EL2] = read_sysreg(dacr32_el2); + sysreg[IFSR32_EL2] = read_sysreg(ifsr32_el2); + + if (has_vhe() || vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY) + sysreg[DBGVCR32_EL2] = read_sysreg(dbgvcr32_el2); +} + +static inline void __hyp_text __sysreg32_restore_state(struct kvm_vcpu *vcpu) +{ + u64 *spsr, *sysreg; + + if (!vcpu_el1_is_32bit(vcpu)) + return; + + spsr = vcpu->arch.ctxt.gp_regs.spsr; + sysreg = vcpu->arch.ctxt.sys_regs; + + write_sysreg(spsr[KVM_SPSR_ABT], spsr_abt); + write_sysreg(spsr[KVM_SPSR_UND], spsr_und); + write_sysreg(spsr[KVM_SPSR_IRQ], spsr_irq); + write_sysreg(spsr[KVM_SPSR_FIQ], spsr_fiq); + + write_sysreg(sysreg[DACR32_EL2], dacr32_el2); + write_sysreg(sysreg[IFSR32_EL2], ifsr32_el2); + + if (has_vhe() || vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY) + write_sysreg(sysreg[DBGVCR32_EL2], dbgvcr32_el2); +} + +#endif /* __ARM64_KVM_HYP_SYSREG_SR_H__ */ diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index b3cb67b63d671..61a8160f0dd94 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -6,7 +6,7 @@ asflags-y := -D__KVM_NVHE_HYPERVISOR__ ccflags-y := -D__KVM_NVHE_HYPERVISOR__ -obj-y := debug-sr.o switch.o tlb.o hyp-init.o ../hyp-entry.o +obj-y := sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o ../hyp-entry.o obj-y := $(patsubst %.o,%.hyp.o,$(obj-y)) extra-y := $(patsubst %.hyp.o,%.hyp.tmp.o,$(obj-y)) diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c index 7f6b8d3dc637a..f08bfb951df60 100644 --- a/arch/arm64/kvm/hyp/nvhe/switch.c +++ b/arch/arm64/kvm/hyp/nvhe/switch.c @@ -5,6 +5,7 @@ */ #include +#include #include #include diff --git a/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c b/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c new file mode 100644 index 0000000000000..710cf28ab1ec9 --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/sysreg-sr.c @@ -0,0 +1,46 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012-2015 - ARM Ltd + * Author: Marc Zyngier + */ + +#include + +#include +#include + +#include +#include +#include +#include + +/* + * Non-VHE: Both host and guest must save everything. + */ + +void __hyp_text __sysreg_save_state_nvhe(struct kvm_cpu_context *ctxt) +{ + __sysreg_save_el1_state(ctxt); + __sysreg_save_common_state(ctxt); + __sysreg_save_user_state(ctxt); + __sysreg_save_el2_return_state(ctxt); +} + +void __hyp_text __sysreg_restore_state_nvhe(struct kvm_cpu_context *ctxt) +{ + __sysreg_restore_el1_state(ctxt); + __sysreg_restore_common_state(ctxt); + __sysreg_restore_user_state(ctxt); + __sysreg_restore_el2_return_state(ctxt); +} + +void __hyp_text __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/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c deleted file mode 100644 index 2493439a5c548..0000000000000 --- a/arch/arm64/kvm/hyp/sysreg-sr.c +++ /dev/null @@ -1,333 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright (C) 2012-2015 - ARM Ltd - * Author: Marc Zyngier - */ - -#include -#include - -#include -#include -#include -#include - -/* - * Non-VHE: Both host and guest must save everything. - * - * VHE: Host and guest must save mdscr_el1 and sp_el0 (and the PC and - * pstate, which are handled as part of the el2 return state) on every - * switch (sp_el0 is being dealt with in the assembly code). - * tpidr_el0 and tpidrro_el0 only need to be switched when going - * to host userspace or a different VCPU. EL1 registers only need to be - * switched when potentially going to run a different VCPU. The latter two - * classes are handled as part of kvm_arch_vcpu_load and kvm_arch_vcpu_put. - */ - -static void __hyp_text __sysreg_save_common_state(struct kvm_cpu_context *ctxt) -{ - ctxt->sys_regs[MDSCR_EL1] = read_sysreg(mdscr_el1); -} - -static void __hyp_text __sysreg_save_user_state(struct kvm_cpu_context *ctxt) -{ - ctxt->sys_regs[TPIDR_EL0] = read_sysreg(tpidr_el0); - ctxt->sys_regs[TPIDRRO_EL0] = read_sysreg(tpidrro_el0); -} - -static void __hyp_text __sysreg_save_el1_state(struct kvm_cpu_context *ctxt) -{ - ctxt->sys_regs[CSSELR_EL1] = read_sysreg(csselr_el1); - ctxt->sys_regs[SCTLR_EL1] = read_sysreg_el1(SYS_SCTLR); - ctxt->sys_regs[CPACR_EL1] = read_sysreg_el1(SYS_CPACR); - ctxt->sys_regs[TTBR0_EL1] = read_sysreg_el1(SYS_TTBR0); - ctxt->sys_regs[TTBR1_EL1] = read_sysreg_el1(SYS_TTBR1); - ctxt->sys_regs[TCR_EL1] = read_sysreg_el1(SYS_TCR); - ctxt->sys_regs[ESR_EL1] = read_sysreg_el1(SYS_ESR); - ctxt->sys_regs[AFSR0_EL1] = read_sysreg_el1(SYS_AFSR0); - ctxt->sys_regs[AFSR1_EL1] = read_sysreg_el1(SYS_AFSR1); - ctxt->sys_regs[FAR_EL1] = read_sysreg_el1(SYS_FAR); - ctxt->sys_regs[MAIR_EL1] = read_sysreg_el1(SYS_MAIR); - ctxt->sys_regs[VBAR_EL1] = read_sysreg_el1(SYS_VBAR); - ctxt->sys_regs[CONTEXTIDR_EL1] = read_sysreg_el1(SYS_CONTEXTIDR); - ctxt->sys_regs[AMAIR_EL1] = read_sysreg_el1(SYS_AMAIR); - ctxt->sys_regs[CNTKCTL_EL1] = read_sysreg_el1(SYS_CNTKCTL); - ctxt->sys_regs[PAR_EL1] = read_sysreg(par_el1); - ctxt->sys_regs[TPIDR_EL1] = read_sysreg(tpidr_el1); - - ctxt->gp_regs.sp_el1 = read_sysreg(sp_el1); - ctxt->gp_regs.elr_el1 = read_sysreg_el1(SYS_ELR); - ctxt->gp_regs.spsr[KVM_SPSR_EL1]= read_sysreg_el1(SYS_SPSR); -} - -static void __hyp_text __sysreg_save_el2_return_state(struct kvm_cpu_context *ctxt) -{ - ctxt->gp_regs.regs.pc = read_sysreg_el2(SYS_ELR); - ctxt->gp_regs.regs.pstate = read_sysreg_el2(SYS_SPSR); - - if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN)) - ctxt->sys_regs[DISR_EL1] = read_sysreg_s(SYS_VDISR_EL2); -} - -void __hyp_text __sysreg_save_state_nvhe(struct kvm_cpu_context *ctxt) -{ - __sysreg_save_el1_state(ctxt); - __sysreg_save_common_state(ctxt); - __sysreg_save_user_state(ctxt); - __sysreg_save_el2_return_state(ctxt); -} - -void sysreg_save_host_state_vhe(struct kvm_cpu_context *ctxt) -{ - __sysreg_save_common_state(ctxt); -} -NOKPROBE_SYMBOL(sysreg_save_host_state_vhe); - -void sysreg_save_guest_state_vhe(struct kvm_cpu_context *ctxt) -{ - __sysreg_save_common_state(ctxt); - __sysreg_save_el2_return_state(ctxt); -} -NOKPROBE_SYMBOL(sysreg_save_guest_state_vhe); - -static void __hyp_text __sysreg_restore_common_state(struct kvm_cpu_context *ctxt) -{ - write_sysreg(ctxt->sys_regs[MDSCR_EL1], mdscr_el1); -} - -static void __hyp_text __sysreg_restore_user_state(struct kvm_cpu_context *ctxt) -{ - write_sysreg(ctxt->sys_regs[TPIDR_EL0], tpidr_el0); - write_sysreg(ctxt->sys_regs[TPIDRRO_EL0], tpidrro_el0); -} - -static void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt) -{ - write_sysreg(ctxt->sys_regs[MPIDR_EL1], vmpidr_el2); - write_sysreg(ctxt->sys_regs[CSSELR_EL1], csselr_el1); - - if (has_vhe() || - !cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { - write_sysreg_el1(ctxt->sys_regs[SCTLR_EL1], SYS_SCTLR); - write_sysreg_el1(ctxt->sys_regs[TCR_EL1], SYS_TCR); - } else if (!ctxt->__hyp_running_vcpu) { - /* - * Must only be done for guest registers, hence the context - * test. We're coming from the host, so SCTLR.M is already - * set. Pairs with nVHE's __activate_traps(). - */ - write_sysreg_el1((ctxt->sys_regs[TCR_EL1] | - TCR_EPD1_MASK | TCR_EPD0_MASK), - SYS_TCR); - isb(); - } - - write_sysreg_el1(ctxt->sys_regs[CPACR_EL1], SYS_CPACR); - write_sysreg_el1(ctxt->sys_regs[TTBR0_EL1], SYS_TTBR0); - write_sysreg_el1(ctxt->sys_regs[TTBR1_EL1], SYS_TTBR1); - write_sysreg_el1(ctxt->sys_regs[ESR_EL1], SYS_ESR); - write_sysreg_el1(ctxt->sys_regs[AFSR0_EL1], SYS_AFSR0); - write_sysreg_el1(ctxt->sys_regs[AFSR1_EL1], SYS_AFSR1); - write_sysreg_el1(ctxt->sys_regs[FAR_EL1], SYS_FAR); - write_sysreg_el1(ctxt->sys_regs[MAIR_EL1], SYS_MAIR); - write_sysreg_el1(ctxt->sys_regs[VBAR_EL1], SYS_VBAR); - write_sysreg_el1(ctxt->sys_regs[CONTEXTIDR_EL1],SYS_CONTEXTIDR); - write_sysreg_el1(ctxt->sys_regs[AMAIR_EL1], SYS_AMAIR); - write_sysreg_el1(ctxt->sys_regs[CNTKCTL_EL1], SYS_CNTKCTL); - write_sysreg(ctxt->sys_regs[PAR_EL1], par_el1); - write_sysreg(ctxt->sys_regs[TPIDR_EL1], tpidr_el1); - - if (!has_vhe() && - cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT) && - ctxt->__hyp_running_vcpu) { - /* - * Must only be done for host registers, hence the context - * test. Pairs with nVHE's __deactivate_traps(). - */ - isb(); - /* - * At this stage, and thanks to the above isb(), S2 is - * deconfigured and disabled. We can now restore the host's - * S1 configuration: SCTLR, and only then TCR. - */ - write_sysreg_el1(ctxt->sys_regs[SCTLR_EL1], SYS_SCTLR); - isb(); - write_sysreg_el1(ctxt->sys_regs[TCR_EL1], SYS_TCR); - } - - write_sysreg(ctxt->gp_regs.sp_el1, sp_el1); - write_sysreg_el1(ctxt->gp_regs.elr_el1, SYS_ELR); - write_sysreg_el1(ctxt->gp_regs.spsr[KVM_SPSR_EL1],SYS_SPSR); -} - -static void __hyp_text -__sysreg_restore_el2_return_state(struct kvm_cpu_context *ctxt) -{ - u64 pstate = ctxt->gp_regs.regs.pstate; - u64 mode = pstate & PSR_AA32_MODE_MASK; - - /* - * Safety check to ensure we're setting the CPU up to enter the guest - * in a less privileged mode. - * - * If we are attempting a return to EL2 or higher in AArch64 state, - * program SPSR_EL2 with M=EL2h and the IL bit set which ensures that - * we'll take an illegal exception state exception immediately after - * the ERET to the guest. Attempts to return to AArch32 Hyp will - * result in an illegal exception return because EL2's execution state - * is determined by SCR_EL3.RW. - */ - if (!(mode & PSR_MODE32_BIT) && mode >= PSR_MODE_EL2t) - pstate = PSR_MODE_EL2h | PSR_IL_BIT; - - write_sysreg_el2(ctxt->gp_regs.regs.pc, SYS_ELR); - write_sysreg_el2(pstate, SYS_SPSR); - - if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN)) - write_sysreg_s(ctxt->sys_regs[DISR_EL1], SYS_VDISR_EL2); -} - -void __hyp_text __sysreg_restore_state_nvhe(struct kvm_cpu_context *ctxt) -{ - __sysreg_restore_el1_state(ctxt); - __sysreg_restore_common_state(ctxt); - __sysreg_restore_user_state(ctxt); - __sysreg_restore_el2_return_state(ctxt); -} - -void sysreg_restore_host_state_vhe(struct kvm_cpu_context *ctxt) -{ - __sysreg_restore_common_state(ctxt); -} -NOKPROBE_SYMBOL(sysreg_restore_host_state_vhe); - -void sysreg_restore_guest_state_vhe(struct kvm_cpu_context *ctxt) -{ - __sysreg_restore_common_state(ctxt); - __sysreg_restore_el2_return_state(ctxt); -} -NOKPROBE_SYMBOL(sysreg_restore_guest_state_vhe); - -void __hyp_text __sysreg32_save_state(struct kvm_vcpu *vcpu) -{ - u64 *spsr, *sysreg; - - if (!vcpu_el1_is_32bit(vcpu)) - return; - - spsr = vcpu->arch.ctxt.gp_regs.spsr; - sysreg = vcpu->arch.ctxt.sys_regs; - - spsr[KVM_SPSR_ABT] = read_sysreg(spsr_abt); - spsr[KVM_SPSR_UND] = read_sysreg(spsr_und); - spsr[KVM_SPSR_IRQ] = read_sysreg(spsr_irq); - spsr[KVM_SPSR_FIQ] = read_sysreg(spsr_fiq); - - sysreg[DACR32_EL2] = read_sysreg(dacr32_el2); - sysreg[IFSR32_EL2] = read_sysreg(ifsr32_el2); - - if (has_vhe() || vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY) - sysreg[DBGVCR32_EL2] = read_sysreg(dbgvcr32_el2); -} - -void __hyp_text __sysreg32_restore_state(struct kvm_vcpu *vcpu) -{ - u64 *spsr, *sysreg; - - if (!vcpu_el1_is_32bit(vcpu)) - return; - - spsr = vcpu->arch.ctxt.gp_regs.spsr; - sysreg = vcpu->arch.ctxt.sys_regs; - - write_sysreg(spsr[KVM_SPSR_ABT], spsr_abt); - write_sysreg(spsr[KVM_SPSR_UND], spsr_und); - write_sysreg(spsr[KVM_SPSR_IRQ], spsr_irq); - write_sysreg(spsr[KVM_SPSR_FIQ], spsr_fiq); - - write_sysreg(sysreg[DACR32_EL2], dacr32_el2); - write_sysreg(sysreg[IFSR32_EL2], ifsr32_el2); - - if (has_vhe() || vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY) - write_sysreg(sysreg[DBGVCR32_EL2], dbgvcr32_el2); -} - -/** - * kvm_vcpu_load_sysregs - Load guest system registers to the physical CPU - * - * @vcpu: The VCPU pointer - * - * Load system registers that do not affect the host's execution, for - * example EL1 system registers on a VHE system where the host kernel - * runs at EL2. This function is called from KVM's vcpu_load() function - * and loading system register state early avoids having to load them on - * every entry to the VM. - */ -void kvm_vcpu_load_sysregs(struct kvm_vcpu *vcpu) -{ - struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt; - struct kvm_cpu_context *host_ctxt; - - if (!has_vhe()) - return; - - host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; - __sysreg_save_user_state(host_ctxt); - - /* - * Load guest EL1 and user state - * - * We must restore the 32-bit state before the sysregs, thanks - * to erratum #852523 (Cortex-A57) or #853709 (Cortex-A72). - */ - __sysreg32_restore_state(vcpu); - __sysreg_restore_user_state(guest_ctxt); - __sysreg_restore_el1_state(guest_ctxt); - - vcpu->arch.sysregs_loaded_on_cpu = true; - - activate_traps_vhe_load(vcpu); -} - -/** - * kvm_vcpu_put_sysregs - Restore host system registers to the physical CPU - * - * @vcpu: The VCPU pointer - * - * Save guest system registers that do not affect the host's execution, for - * example EL1 system registers on a VHE system where the host kernel - * runs at EL2. This function is called from KVM's vcpu_put() function - * and deferring saving system register state until we're no longer running the - * VCPU avoids having to save them on every exit from the VM. - */ -void kvm_vcpu_put_sysregs(struct kvm_vcpu *vcpu) -{ - struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt; - struct kvm_cpu_context *host_ctxt; - - if (!has_vhe()) - return; - - host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; - deactivate_traps_vhe_put(); - - __sysreg_save_el1_state(guest_ctxt); - __sysreg_save_user_state(guest_ctxt); - __sysreg32_save_state(vcpu); - - /* Restore host user state */ - __sysreg_restore_user_state(host_ctxt); - - vcpu->arch.sysregs_loaded_on_cpu = false; -} - -void __hyp_text __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/vhe/Makefile b/arch/arm64/kvm/hyp/vhe/Makefile index 62bdaf272b03a..2801582a739a5 100644 --- a/arch/arm64/kvm/hyp/vhe/Makefile +++ b/arch/arm64/kvm/hyp/vhe/Makefile @@ -6,7 +6,7 @@ asflags-y := -D__KVM_VHE_HYPERVISOR__ ccflags-y := -D__KVM_VHE_HYPERVISOR__ -obj-y := debug-sr.o switch.o tlb.o ../hyp-entry.o +obj-y := sysreg-sr.o debug-sr.o switch.o tlb.o ../hyp-entry.o # KVM code is run at a different exception code with a different map, so # compiler instrumentation that inserts callbacks or checks into the code may diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c index e8d76cab44e43..c0d33deba77e6 100644 --- a/arch/arm64/kvm/hyp/vhe/switch.c +++ b/arch/arm64/kvm/hyp/vhe/switch.c @@ -120,7 +120,7 @@ static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) * HCR_EL2.TGE. * * We have already configured the guest's stage 1 translation in - * kvm_vcpu_load_sysregs above. We must now call __activate_vm + * kvm_vcpu_load_sysregs_vhe above. We must now call __activate_vm * before __activate_traps, because __activate_vm configures * stage 2 translation, and __activate_traps clear HCR_EL2.TGE * (among other things). diff --git a/arch/arm64/kvm/hyp/vhe/sysreg-sr.c b/arch/arm64/kvm/hyp/vhe/sysreg-sr.c new file mode 100644 index 0000000000000..996471e4c1380 --- /dev/null +++ b/arch/arm64/kvm/hyp/vhe/sysreg-sr.c @@ -0,0 +1,114 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012-2015 - ARM Ltd + * Author: Marc Zyngier + */ + +#include + +#include +#include + +#include +#include +#include +#include + +/* + * VHE: Host and guest must save mdscr_el1 and sp_el0 (and the PC and + * pstate, which are handled as part of the el2 return state) on every + * switch (sp_el0 is being dealt with in the assembly code). + * tpidr_el0 and tpidrro_el0 only need to be switched when going + * to host userspace or a different VCPU. EL1 registers only need to be + * switched when potentially going to run a different VCPU. The latter two + * classes are handled as part of kvm_arch_vcpu_load and kvm_arch_vcpu_put. + */ + +void sysreg_save_host_state_vhe(struct kvm_cpu_context *ctxt) +{ + __sysreg_save_common_state(ctxt); +} +NOKPROBE_SYMBOL(sysreg_save_host_state_vhe); + +void sysreg_save_guest_state_vhe(struct kvm_cpu_context *ctxt) +{ + __sysreg_save_common_state(ctxt); + __sysreg_save_el2_return_state(ctxt); +} +NOKPROBE_SYMBOL(sysreg_save_guest_state_vhe); + +void sysreg_restore_host_state_vhe(struct kvm_cpu_context *ctxt) +{ + __sysreg_restore_common_state(ctxt); +} +NOKPROBE_SYMBOL(sysreg_restore_host_state_vhe); + +void sysreg_restore_guest_state_vhe(struct kvm_cpu_context *ctxt) +{ + __sysreg_restore_common_state(ctxt); + __sysreg_restore_el2_return_state(ctxt); +} +NOKPROBE_SYMBOL(sysreg_restore_guest_state_vhe); + +/** + * kvm_vcpu_load_sysregs_vhe - Load guest system registers to the physical CPU + * + * @vcpu: The VCPU pointer + * + * Load system registers that do not affect the host's execution, for + * example EL1 system registers on a VHE system where the host kernel + * runs at EL2. This function is called from KVM's vcpu_load() function + * and loading system register state early avoids having to load them on + * every entry to the VM. + */ +void kvm_vcpu_load_sysregs_vhe(struct kvm_vcpu *vcpu) +{ + struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt; + struct kvm_cpu_context *host_ctxt; + + host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; + __sysreg_save_user_state(host_ctxt); + + /* + * Load guest EL1 and user state + * + * We must restore the 32-bit state before the sysregs, thanks + * to erratum #852523 (Cortex-A57) or #853709 (Cortex-A72). + */ + __sysreg32_restore_state(vcpu); + __sysreg_restore_user_state(guest_ctxt); + __sysreg_restore_el1_state(guest_ctxt); + + vcpu->arch.sysregs_loaded_on_cpu = true; + + activate_traps_vhe_load(vcpu); +} + +/** + * kvm_vcpu_put_sysregs_vhe - Restore host system registers to the physical CPU + * + * @vcpu: The VCPU pointer + * + * Save guest system registers that do not affect the host's execution, for + * example EL1 system registers on a VHE system where the host kernel + * runs at EL2. This function is called from KVM's vcpu_put() function + * and deferring saving system register state until we're no longer running the + * VCPU avoids having to save them on every exit from the VM. + */ +void kvm_vcpu_put_sysregs_vhe(struct kvm_vcpu *vcpu) +{ + struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt; + struct kvm_cpu_context *host_ctxt; + + host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; + deactivate_traps_vhe_put(); + + __sysreg_save_el1_state(guest_ctxt); + __sysreg_save_user_state(guest_ctxt); + __sysreg32_save_state(vcpu); + + /* Restore host user state */ + __sysreg_restore_user_state(host_ctxt); + + vcpu->arch.sysregs_loaded_on_cpu = false; +}