diff options
| -rw-r--r-- | arch/powerpc/kvm/booke.c | 44 | ||||
| -rw-r--r-- | arch/powerpc/kvm/bookehv_interrupts.S | 37 | ||||
| -rw-r--r-- | arch/powerpc/kvm/e500_mmu_host.c | 92 |
3 files changed, 145 insertions, 28 deletions
diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index 50df5e3072cc..97bcde2dc075 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -819,6 +819,28 @@ static void kvmppc_restart_interrupt(struct kvm_vcpu *vcpu, } } +static int kvmppc_resume_inst_load(struct kvm_run *run, struct kvm_vcpu *vcpu, + enum emulation_result emulated, u32 last_inst) +{ + switch (emulated) { + case EMULATE_AGAIN: + return RESUME_GUEST; + + case EMULATE_FAIL: + pr_debug("%s: load instruction from guest address %lx failed\n", + __func__, vcpu->arch.pc); + /* For debugging, encode the failing instruction and + * report it to userspace. */ + run->hw.hardware_exit_reason = ~0ULL << 32; + run->hw.hardware_exit_reason |= last_inst; + kvmppc_core_queue_program(vcpu, ESR_PIL); + return RESUME_HOST; + + default: + BUG(); + } +} + /** * kvmppc_handle_exit * @@ -830,6 +852,8 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu, int r = RESUME_HOST; int s; int idx; + u32 last_inst = KVM_INST_FETCH_FAILED; + enum emulation_result emulated = EMULATE_DONE; /* update before a new last_exit_type is rewritten */ kvmppc_update_timing_stats(vcpu); @@ -837,6 +861,20 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu, /* restart interrupts if they were meant for the host */ kvmppc_restart_interrupt(vcpu, exit_nr); + /* + * get last instruction before beeing preempted + * TODO: for e6500 check also BOOKE_INTERRUPT_LRAT_ERROR & ESR_DATA + */ + switch (exit_nr) { + case BOOKE_INTERRUPT_DATA_STORAGE: + case BOOKE_INTERRUPT_DTLB_MISS: + case BOOKE_INTERRUPT_HV_PRIV: + emulated = kvmppc_get_last_inst(vcpu, false, &last_inst); + break; + default: + break; + } + local_irq_enable(); trace_kvm_exit(exit_nr, vcpu); @@ -845,6 +883,11 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu, run->exit_reason = KVM_EXIT_UNKNOWN; run->ready_for_interrupt_injection = 1; + if (emulated != EMULATE_DONE) { + r = kvmppc_resume_inst_load(run, vcpu, emulated, last_inst); + goto out; + } + switch (exit_nr) { case BOOKE_INTERRUPT_MACHINE_CHECK: printk("MACHINE CHECK: %lx\n", mfspr(SPRN_MCSR)); @@ -1134,6 +1177,7 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu, BUG(); } +out: /* * To avoid clobbering exit_reason, only check for signals if we * aren't already exiting to userspace for some other reason. diff --git a/arch/powerpc/kvm/bookehv_interrupts.S b/arch/powerpc/kvm/bookehv_interrupts.S index 6ff448046301..e000b397ece3 100644 --- a/arch/powerpc/kvm/bookehv_interrupts.S +++ b/arch/powerpc/kvm/bookehv_interrupts.S @@ -121,38 +121,14 @@ 1: .if \flags & NEED_EMU - /* - * This assumes you have external PID support. - * To support a bookehv CPU without external PID, you'll - * need to look up the TLB entry and create a temporary mapping. - * - * FIXME: we don't currently handle if the lwepx faults. PR-mode - * booke doesn't handle it either. Since Linux doesn't use - * broadcast tlbivax anymore, the only way this should happen is - * if the guest maps its memory execute-but-not-read, or if we - * somehow take a TLB miss in the middle of this entry code and - * evict the relevant entry. On e500mc, all kernel lowmem is - * bolted into TLB1 large page mappings, and we don't use - * broadcast invalidates, so we should not take a TLB miss here. - * - * Later we'll need to deal with faults here. Disallowing guest - * mappings that are execute-but-not-read could be an option on - * e500mc, but not on chips with an LRAT if it is used. - */ - - mfspr r3, SPRN_EPLC /* will already have correct ELPID and EGS */ PPC_STL r15, VCPU_GPR(R15)(r4) PPC_STL r16, VCPU_GPR(R16)(r4) PPC_STL r17, VCPU_GPR(R17)(r4) PPC_STL r18, VCPU_GPR(R18)(r4) PPC_STL r19, VCPU_GPR(R19)(r4) - mr r8, r3 PPC_STL r20, VCPU_GPR(R20)(r4) - rlwimi r8, r6, EPC_EAS_SHIFT - MSR_IR_LG, EPC_EAS PPC_STL r21, VCPU_GPR(R21)(r4) - rlwimi r8, r6, EPC_EPR_SHIFT - MSR_PR_LG, EPC_EPR PPC_STL r22, VCPU_GPR(R22)(r4) - rlwimi r8, r10, EPC_EPID_SHIFT, EPC_EPID PPC_STL r23, VCPU_GPR(R23)(r4) PPC_STL r24, VCPU_GPR(R24)(r4) PPC_STL r25, VCPU_GPR(R25)(r4) @@ -162,10 +138,15 @@ PPC_STL r29, VCPU_GPR(R29)(r4) PPC_STL r30, VCPU_GPR(R30)(r4) PPC_STL r31, VCPU_GPR(R31)(r4) - mtspr SPRN_EPLC, r8 - isync - lwepx r9, 0, r5 - mtspr SPRN_EPLC, r3 + + /* + * We don't use external PID support. lwepx faults would need to be + * handled by KVM and this implies aditional code in DO_KVM (for + * DTB_MISS, DSI and LRAT) to check ESR[EPID] and EPLC[EGS] which + * is too intrusive for the host. Get last instuction in + * kvmppc_get_last_inst(). + */ + li r9, KVM_INST_FETCH_FAILED stw r9, VCPU_LAST_INST(r4) .endif diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c index 4385c14fca84..41508267b0e2 100644 --- a/arch/powerpc/kvm/e500_mmu_host.c +++ b/arch/powerpc/kvm/e500_mmu_host.c @@ -610,11 +610,103 @@ void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 eaddr, gpa_t gpaddr, } } +#ifdef CONFIG_KVM_BOOKE_HV +int kvmppc_load_last_inst(struct kvm_vcpu *vcpu, enum instruction_type type, + u32 *instr) +{ + gva_t geaddr; + hpa_t addr; + hfn_t pfn; + hva_t eaddr; + u32 mas1, mas2, mas3; + u64 mas7_mas3; + struct page *page; + unsigned int addr_space, psize_shift; + bool pr; + unsigned long flags; + + /* Search TLB for guest pc to get the real address */ + geaddr = kvmppc_get_pc(vcpu); + + addr_space = (vcpu->arch.shared->msr & MSR_IS) >> MSR_IR_LG; + + local_irq_save(flags); + mtspr(SPRN_MAS6, (vcpu->arch.pid << MAS6_SPID_SHIFT) | addr_space); + mtspr(SPRN_MAS5, MAS5_SGS | vcpu->kvm->arch.lpid); + asm volatile("tlbsx 0, %[geaddr]\n" : : + [geaddr] "r" (geaddr)); + mtspr(SPRN_MAS5, 0); + mtspr(SPRN_MAS8, 0); + mas1 = mfspr(SPRN_MAS1); + mas2 = mfspr(SPRN_MAS2); + mas3 = mfspr(SPRN_MAS3); +#ifdef CONFIG_64BIT + mas7_mas3 = mfspr(SPRN_MAS7_MAS3); +#else + mas7_mas3 = ((u64)mfspr(SPRN_MAS7) << 32) | mas3; +#endif + local_irq_restore(flags); + + /* + * If the TLB entry for guest pc was evicted, return to the guest. + * There are high chances to find a valid TLB entry next time. + */ + if (!(mas1 & MAS1_VALID)) + return EMULATE_AGAIN; + + /* + * Another thread may rewrite the TLB entry in parallel, don't + * execute from the address if the execute permission is not set + */ + pr = vcpu->arch.shared->msr & MSR_PR; + if (unlikely((pr && !(mas3 & MAS3_UX)) || + (!pr && !(mas3 & MAS3_SX)))) { + pr_err_ratelimited( + "%s: Instuction emulation from guest addres %08lx without execute permission\n", + __func__, geaddr); + return EMULATE_AGAIN; + } + + /* + * The real address will be mapped by a cacheable, memory coherent, + * write-back page. Check for mismatches when LRAT is used. + */ + if (has_feature(vcpu, VCPU_FTR_MMU_V2) && + unlikely((mas2 & MAS2_I) || (mas2 & MAS2_W) || !(mas2 & MAS2_M))) { + pr_err_ratelimited( + "%s: Instuction emulation from guest addres %08lx mismatches storage attributes\n", + __func__, geaddr); + return EMULATE_AGAIN; + } + + /* Get pfn */ + psize_shift = MAS1_GET_TSIZE(mas1) + 10; + addr = (mas7_mas3 & (~0ULL << psize_shift)) | + (geaddr & ((1ULL << psize_shift) - 1ULL)); + pfn = addr >> PAGE_SHIFT; + + /* Guard against emulation from devices area */ + if (unlikely(!page_is_ram(pfn))) { + pr_err_ratelimited("%s: Instruction emulation from non-RAM host addres %08llx is not supported\n", + __func__, addr); + return EMULATE_AGAIN; + } + + /* Map a page and get guest's instruction */ + page = pfn_to_page(pfn); + eaddr = (unsigned long)kmap_atomic(page); + *instr = *(u32 *)(eaddr | (unsigned long)(addr & ~PAGE_MASK)); + kunmap_atomic((u32 *)eaddr); + + return EMULATE_DONE; +} +#else int kvmppc_load_last_inst(struct kvm_vcpu *vcpu, enum instruction_type type, u32 *instr) { return EMULATE_AGAIN; } +#endif /************* MMU Notifiers *************/ |