diff options
Diffstat (limited to 'arch/arm64/include')
| -rw-r--r-- | arch/arm64/include/asm/el2_setup.h | 38 | ||||
| -rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 50 | ||||
| -rw-r--r-- | arch/arm64/include/asm/sysreg.h | 11 |
3 files changed, 92 insertions, 7 deletions
diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h index b37da3ee8529..99a7c0235e6d 100644 --- a/arch/arm64/include/asm/el2_setup.h +++ b/arch/arm64/include/asm/el2_setup.h @@ -24,22 +24,48 @@ * ID_AA64MMFR4_EL1.E2H0 < 0. On such CPUs HCR_EL2.E2H is RES1, but it * can reset into an UNKNOWN state and might not read as 1 until it has * been initialized explicitly. - * - * Fruity CPUs seem to have HCR_EL2.E2H set to RAO/WI, but - * don't advertise it (they predate this relaxation). - * * Initalize HCR_EL2.E2H so that later code can rely upon HCR_EL2.E2H * indicating whether the CPU is running in E2H mode. */ mrs_s x1, SYS_ID_AA64MMFR4_EL1 sbfx x1, x1, #ID_AA64MMFR4_EL1_E2H0_SHIFT, #ID_AA64MMFR4_EL1_E2H0_WIDTH cmp x1, #0 - b.ge .LnVHE_\@ + b.lt .LnE2H0_\@ + /* + * Unfortunately, HCR_EL2.E2H can be RES1 even if not advertised + * as such via ID_AA64MMFR4_EL1.E2H0: + * + * - Fruity CPUs predate the !FEAT_E2H0 relaxation, and seem to + * have HCR_EL2.E2H implemented as RAO/WI. + * + * - On CPUs that lack FEAT_FGT, a hypervisor can't trap guest + * reads of ID_AA64MMFR4_EL1 to advertise !FEAT_E2H0. NV + * guests on these hosts can write to HCR_EL2.E2H without + * trapping to the hypervisor, but these writes have no + * functional effect. + * + * Handle both cases by checking for an essential VHE property + * (system register remapping) to decide whether we're + * effectively VHE-only or not. + */ + msr_hcr_el2 x0 // Setup HCR_EL2 as nVHE + isb + mov x1, #1 // Write something to FAR_EL1 + msr far_el1, x1 + isb + mov x1, #2 // Try to overwrite it via FAR_EL2 + msr far_el2, x1 + isb + mrs x1, far_el1 // If we see the latest write in FAR_EL1, + cmp x1, #2 // we can safely assume we are VHE only. + b.ne .LnVHE_\@ // Otherwise, we know that nVHE works. + +.LnE2H0_\@: orr x0, x0, #HCR_E2H -.LnVHE_\@: msr_hcr_el2 x0 isb +.LnVHE_\@: .endm .macro __init_el2_sctlr diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index b763293281c8..64302c438355 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -816,6 +816,11 @@ struct kvm_vcpu_arch { u64 hcrx_el2; u64 mdcr_el2; + struct { + u64 r; + u64 w; + } fgt[__NR_FGT_GROUP_IDS__]; + /* Exception Information */ struct kvm_vcpu_fault_info fault; @@ -1600,6 +1605,51 @@ static inline bool kvm_arch_has_irq_bypass(void) void compute_fgu(struct kvm *kvm, enum fgt_group_id fgt); void get_reg_fixed_bits(struct kvm *kvm, enum vcpu_sysreg reg, u64 *res0, u64 *res1); void check_feature_map(void); +void kvm_vcpu_load_fgt(struct kvm_vcpu *vcpu); + +static __always_inline enum fgt_group_id __fgt_reg_to_group_id(enum vcpu_sysreg reg) +{ + switch (reg) { + case HFGRTR_EL2: + case HFGWTR_EL2: + return HFGRTR_GROUP; + case HFGITR_EL2: + return HFGITR_GROUP; + case HDFGRTR_EL2: + case HDFGWTR_EL2: + return HDFGRTR_GROUP; + case HAFGRTR_EL2: + return HAFGRTR_GROUP; + case HFGRTR2_EL2: + case HFGWTR2_EL2: + return HFGRTR2_GROUP; + case HFGITR2_EL2: + return HFGITR2_GROUP; + case HDFGRTR2_EL2: + case HDFGWTR2_EL2: + return HDFGRTR2_GROUP; + default: + BUILD_BUG_ON(1); + } +} +#define vcpu_fgt(vcpu, reg) \ + ({ \ + enum fgt_group_id id = __fgt_reg_to_group_id(reg); \ + u64 *p; \ + switch (reg) { \ + case HFGWTR_EL2: \ + case HDFGWTR_EL2: \ + case HFGWTR2_EL2: \ + case HDFGWTR2_EL2: \ + p = &(vcpu)->arch.fgt[id].w; \ + break; \ + default: \ + p = &(vcpu)->arch.fgt[id].r; \ + break; \ + } \ + \ + p; \ + }) #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index 6455db1b54fd..c231d2a3e515 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -1220,10 +1220,19 @@ __val; \ }) +/* + * The "Z" constraint combined with the "%x0" template should be enough + * to force XZR generation if (v) is a constant 0 value but LLVM does not + * yet understand that modifier/constraint combo so a conditional is required + * to nudge the compiler into using XZR as a source for a 0 constant value. + */ #define write_sysreg_s(v, r) do { \ u64 __val = (u64)(v); \ u32 __maybe_unused __check_r = (u32)(r); \ - asm volatile(__msr_s(r, "%x0") : : "rZ" (__val)); \ + if (__builtin_constant_p(__val) && __val == 0) \ + asm volatile(__msr_s(r, "xzr")); \ + else \ + asm volatile(__msr_s(r, "%x0") : : "r" (__val)); \ } while (0) /* |