| Message ID | 1401724216-26486-4-git-send-email-mihai.caraman@freescale.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 06/02/2014 05:50 PM, Mihai Caraman wrote: > On book3e, guest last instruction is read on the exit path using load > external pid (lwepx) dedicated instruction. This load operation may fail > due to TLB eviction and execute-but-not-read entries. > > This patch lay down the path for an alternative solution to read the guest > last instruction, by allowing kvmppc_get_lat_inst() function to fail. > Architecture specific implmentations of kvmppc_load_last_inst() may read > last guest instruction and instruct the emulation layer to re-execute the > guest in case of failure. > > Make kvmppc_get_last_inst() definition common between architectures. > > Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com> > --- > v3: > - these changes compile on book3s, please validate the functionality and > do the necessary adaptations! > - rework patch description > - add common definition for kvmppc_get_last_inst() > - check return values in book3s code > > v2: > - integrated kvmppc_get_last_inst() in book3s code and checked build > - addressed cosmetic feedback > > arch/powerpc/include/asm/kvm_book3s.h | 28 ++------ > arch/powerpc/include/asm/kvm_booke.h | 7 +- > arch/powerpc/include/asm/kvm_ppc.h | 16 +++++ > arch/powerpc/kvm/book3s_64_mmu_hv.c | 16 ++--- > arch/powerpc/kvm/book3s_paired_singles.c | 38 ++++++---- > arch/powerpc/kvm/book3s_pr.c | 116 +++++++++++++++++-------------- > arch/powerpc/kvm/booke.c | 3 + > arch/powerpc/kvm/e500_mmu_host.c | 5 ++ > arch/powerpc/kvm/emulate.c | 18 +++-- > arch/powerpc/kvm/powerpc.c | 10 ++- > 10 files changed, 142 insertions(+), 115 deletions(-) > > diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h > index f52f656..3409572 100644 > --- a/arch/powerpc/include/asm/kvm_book3s.h > +++ b/arch/powerpc/include/asm/kvm_book3s.h > @@ -274,30 +274,14 @@ static inline bool kvmppc_need_byteswap(struct kvm_vcpu *vcpu) > return (kvmppc_get_msr(vcpu) & MSR_LE) != (MSR_KERNEL & MSR_LE); > } > > -static inline u32 kvmppc_get_last_inst_internal(struct kvm_vcpu *vcpu, ulong pc) > +static inline int kvmppc_load_last_inst(struct kvm_vcpu *vcpu, bool prev, Please make prev an enum :) > + u32 *inst) > { > - /* Load the instruction manually if it failed to do so in the > - * exit path */ > - if (vcpu->arch.last_inst == KVM_INST_FETCH_FAILED) > - kvmppc_ld(vcpu, &pc, sizeof(u32), &vcpu->arch.last_inst, false); > + ulong pc = kvmppc_get_pc(vcpu); > > - return kvmppc_need_byteswap(vcpu) ? swab32(vcpu->arch.last_inst) : > - vcpu->arch.last_inst; > -} > - > -static inline u32 kvmppc_get_last_inst(struct kvm_vcpu *vcpu) > -{ > - return kvmppc_get_last_inst_internal(vcpu, kvmppc_get_pc(vcpu)); > -} > - > -/* > - * Like kvmppc_get_last_inst(), but for fetching a sc instruction. > - * Because the sc instruction sets SRR0 to point to the following > - * instruction, we have to fetch from pc - 4. > - */ > -static inline u32 kvmppc_get_last_sc(struct kvm_vcpu *vcpu) > -{ > - return kvmppc_get_last_inst_internal(vcpu, kvmppc_get_pc(vcpu) - 4); > + if (prev) > + pc -= 4; > + return kvmppc_ld(vcpu, &pc, sizeof(u32), &vcpu->arch.last_inst, false); > } In this case we're already in the slow path. Can we move this into a .c file instead? That would unify it with booke and ... > > static inline ulong kvmppc_get_fault_dar(struct kvm_vcpu *vcpu) > diff --git a/arch/powerpc/include/asm/kvm_booke.h b/arch/powerpc/include/asm/kvm_booke.h > index c7aed61..1e28371 100644 > --- a/arch/powerpc/include/asm/kvm_booke.h > +++ b/arch/powerpc/include/asm/kvm_booke.h > @@ -33,6 +33,8 @@ > #define KVMPPC_INST_EHPRIV_DEBUG (KVMPPC_INST_EHPRIV | \ > (EHPRIV_OC_DEBUG << EHPRIV_OC_SHIFT)) > > +extern int kvmppc_load_last_inst(struct kvm_vcpu *vcpu, bool prev, u32 *inst); ... allow us to move this to a common header file :). > + > static inline void kvmppc_set_gpr(struct kvm_vcpu *vcpu, int num, ulong val) > { > vcpu->arch.gpr[num] = val; > @@ -69,11 +71,6 @@ static inline bool kvmppc_need_byteswap(struct kvm_vcpu *vcpu) > return false; > } > > -static inline u32 kvmppc_get_last_inst(struct kvm_vcpu *vcpu) > -{ > - return vcpu->arch.last_inst; > -} > - > static inline void kvmppc_set_ctr(struct kvm_vcpu *vcpu, ulong val) > { > vcpu->arch.ctr = val; > diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h > index 4a7cc45..619be2f 100644 > --- a/arch/powerpc/include/asm/kvm_ppc.h > +++ b/arch/powerpc/include/asm/kvm_ppc.h > @@ -234,6 +234,22 @@ struct kvmppc_ops { > extern struct kvmppc_ops *kvmppc_hv_ops; > extern struct kvmppc_ops *kvmppc_pr_ops; > > +static inline int kvmppc_get_last_inst(struct kvm_vcpu *vcpu, bool prev, > + u32 *inst) > +{ > + int ret = EMULATE_DONE; > + > + /* Load the instruction manually if it failed to do so in the > + * exit path */ > + if (vcpu->arch.last_inst == KVM_INST_FETCH_FAILED) > + ret = kvmppc_load_last_inst(vcpu, prev, &vcpu->arch.last_inst); > + > + *inst = kvmppc_need_byteswap(vcpu) ? swab32(vcpu->arch.last_inst) : > + vcpu->arch.last_inst; > + > + return ret; > +} > + > static inline bool is_kvmppc_hv_enabled(struct kvm *kvm) > { > return kvm->arch.kvm_ops == kvmppc_hv_ops; > diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c > index 8056107..2ffb3dd 100644 > --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c > +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c > @@ -530,21 +530,13 @@ static int instruction_is_store(unsigned int instr) > static int kvmppc_hv_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu, > unsigned long gpa, gva_t ea, int is_store) > { > - int ret; > u32 last_inst; > - unsigned long srr0 = kvmppc_get_pc(vcpu); > > - /* We try to load the last instruction. We don't let > - * emulate_instruction do it as it doesn't check what > - * kvmppc_ld returns. > + /* > * If we fail, we just return to the guest and try executing it again. > */ > - if (vcpu->arch.last_inst == KVM_INST_FETCH_FAILED) { > - ret = kvmppc_ld(vcpu, &srr0, sizeof(u32), &last_inst, false); > - if (ret != EMULATE_DONE || last_inst == KVM_INST_FETCH_FAILED) > - return RESUME_GUEST; > - vcpu->arch.last_inst = last_inst; > - } > + if (kvmppc_get_last_inst(vcpu, false, &last_inst) != EMULATE_DONE) > + return RESUME_GUEST; > > /* > * WARNING: We do not know for sure whether the instruction we just > @@ -558,7 +550,7 @@ static int kvmppc_hv_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu, > * we just return and retry the instruction. > */ > > - if (instruction_is_store(kvmppc_get_last_inst(vcpu)) != !!is_store) > + if (instruction_is_store(last_inst) != !!is_store) > return RESUME_GUEST; > > /* > diff --git a/arch/powerpc/kvm/book3s_paired_singles.c b/arch/powerpc/kvm/book3s_paired_singles.c > index 6c8011f..6362ad4 100644 > --- a/arch/powerpc/kvm/book3s_paired_singles.c > +++ b/arch/powerpc/kvm/book3s_paired_singles.c > @@ -639,26 +639,36 @@ static int kvmppc_ps_one_in(struct kvm_vcpu *vcpu, bool rc, > > int kvmppc_emulate_paired_single(struct kvm_run *run, struct kvm_vcpu *vcpu) > { > - u32 inst = kvmppc_get_last_inst(vcpu); > + u32 inst; > enum emulation_result emulated = EMULATE_DONE; > + int ax_rd, ax_ra, ax_rb, ax_rc; > + short full_d; > + u64 *fpr_d, *fpr_a, *fpr_b, *fpr_c; > > - int ax_rd = inst_get_field(inst, 6, 10); > - int ax_ra = inst_get_field(inst, 11, 15); > - int ax_rb = inst_get_field(inst, 16, 20); > - int ax_rc = inst_get_field(inst, 21, 25); > - short full_d = inst_get_field(inst, 16, 31); > - > - u64 *fpr_d = &VCPU_FPR(vcpu, ax_rd); > - u64 *fpr_a = &VCPU_FPR(vcpu, ax_ra); > - u64 *fpr_b = &VCPU_FPR(vcpu, ax_rb); > - u64 *fpr_c = &VCPU_FPR(vcpu, ax_rc); > - > - bool rcomp = (inst & 1) ? true : false; > - u32 cr = kvmppc_get_cr(vcpu); > + bool rcomp; > + u32 cr; > #ifdef DEBUG > int i; > #endif > > + emulated = kvmppc_get_last_inst(vcpu, false, &inst); > + if (emulated != EMULATE_DONE) > + return emulated; > + > + ax_rd = inst_get_field(inst, 6, 10); > + ax_ra = inst_get_field(inst, 11, 15); > + ax_rb = inst_get_field(inst, 16, 20); > + ax_rc = inst_get_field(inst, 21, 25); > + full_d = inst_get_field(inst, 16, 31); > + > + fpr_d = &VCPU_FPR(vcpu, ax_rd); > + fpr_a = &VCPU_FPR(vcpu, ax_ra); > + fpr_b = &VCPU_FPR(vcpu, ax_rb); > + fpr_c = &VCPU_FPR(vcpu, ax_rc); > + > + rcomp = (inst & 1) ? true : false; > + cr = kvmppc_get_cr(vcpu); > + > if (!kvmppc_inst_is_paired_single(vcpu, inst)) > return EMULATE_FAIL; > > diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c > index 23367a7..48b633c 100644 > --- a/arch/powerpc/kvm/book3s_pr.c > +++ b/arch/powerpc/kvm/book3s_pr.c > @@ -637,42 +637,6 @@ static void kvmppc_giveup_fac(struct kvm_vcpu *vcpu, ulong fac) > #endif > } > > -static int kvmppc_read_inst(struct kvm_vcpu *vcpu) > -{ > - ulong srr0 = kvmppc_get_pc(vcpu); > - u32 last_inst = kvmppc_get_last_inst(vcpu); > - int ret; > - > - ret = kvmppc_ld(vcpu, &srr0, sizeof(u32), &last_inst, false); > - if (ret == -ENOENT) { > - ulong msr = kvmppc_get_msr(vcpu); > - > - msr = kvmppc_set_field(msr, 33, 33, 1); > - msr = kvmppc_set_field(msr, 34, 36, 0); > - msr = kvmppc_set_field(msr, 42, 47, 0); > - kvmppc_set_msr_fast(vcpu, msr); > - kvmppc_book3s_queue_irqprio(vcpu, BOOK3S_INTERRUPT_INST_STORAGE); > - return EMULATE_AGAIN; > - } > - > - return EMULATE_DONE; > -} > - > -static int kvmppc_check_ext(struct kvm_vcpu *vcpu, unsigned int exit_nr) > -{ > - > - /* Need to do paired single emulation? */ > - if (!(vcpu->arch.hflags & BOOK3S_HFLAG_PAIRED_SINGLE)) > - return EMULATE_DONE; > - > - /* Read out the instruction */ > - if (kvmppc_read_inst(vcpu) == EMULATE_DONE) > - /* Need to emulate */ > - return EMULATE_FAIL; > - > - return EMULATE_AGAIN; > -} > - > /* Handle external providers (FPU, Altivec, VSX) */ > static int kvmppc_handle_ext(struct kvm_vcpu *vcpu, unsigned int exit_nr, > ulong msr) > @@ -977,15 +941,24 @@ int kvmppc_handle_exit_pr(struct kvm_run *run, struct kvm_vcpu *vcpu, > { > enum emulation_result er; > ulong flags; > + u32 last_inst; > + int emul; > > program_interrupt: > flags = vcpu->arch.shadow_srr1 & 0x1f0000ull; > > + emul = kvmppc_get_last_inst(vcpu, false, &last_inst); > + if (emul != EMULATE_DONE) { > + r = RESUME_GUEST; > + break; > + } > + > if (kvmppc_get_msr(vcpu) & MSR_PR) { > #ifdef EXIT_DEBUG > - printk(KERN_INFO "Userspace triggered 0x700 exception at 0x%lx (0x%x)\n", kvmppc_get_pc(vcpu), kvmppc_get_last_inst(vcpu)); > + pr_info("Userspace triggered 0x700 exception at\n" I don't think we want the \n here :). > + "0x%lx (0x%x)\n", kvmppc_get_pc(vcpu), last_inst); > #endif > - if ((kvmppc_get_last_inst(vcpu) & 0xff0007ff) != > + if ((last_inst & 0xff0007ff) != > (INS_DCBZ & 0xfffffff7)) { > kvmppc_core_queue_program(vcpu, flags); > r = RESUME_GUEST; > @@ -1004,7 +977,7 @@ program_interrupt: > break; > case EMULATE_FAIL: > printk(KERN_CRIT "%s: emulation at %lx failed (%08x)\n", > - __func__, kvmppc_get_pc(vcpu), kvmppc_get_last_inst(vcpu)); > + __func__, kvmppc_get_pc(vcpu), last_inst); > kvmppc_core_queue_program(vcpu, flags); > r = RESUME_GUEST; > break; > @@ -1021,8 +994,25 @@ program_interrupt: > break; > } > case BOOK3S_INTERRUPT_SYSCALL: > + { > + u32 last_sc; > + int emul; > + > + /* Get last sc for papr */ > + if (vcpu->arch.papr_enabled) { > + /* > + * The sc instuction sets SRR0 to point to the next inst > + */ > + emul = kvmppc_get_last_inst(vcpu, true, &last_sc); > + if (emul != EMULATE_DONE) { > + kvmppc_set_pc(vcpu, kvmppc_get_pc(vcpu) - 4); > + r = RESUME_GUEST; > + break; > + } > + } > + > if (vcpu->arch.papr_enabled && > - (kvmppc_get_last_sc(vcpu) == 0x44000022) && > + (last_sc == 0x44000022) && > !(kvmppc_get_msr(vcpu) & MSR_PR)) { > /* SC 1 papr hypercalls */ > ulong cmd = kvmppc_get_gpr(vcpu, 3); > @@ -1067,36 +1057,53 @@ program_interrupt: > r = RESUME_GUEST; > } > break; > + } > case BOOK3S_INTERRUPT_FP_UNAVAIL: > case BOOK3S_INTERRUPT_ALTIVEC: > case BOOK3S_INTERRUPT_VSX: > { > int ext_msr = 0; > + int emul; > + u32 last_inst; > > - switch (exit_nr) { > - case BOOK3S_INTERRUPT_FP_UNAVAIL: ext_msr = MSR_FP; break; > - case BOOK3S_INTERRUPT_ALTIVEC: ext_msr = MSR_VEC; break; > - case BOOK3S_INTERRUPT_VSX: ext_msr = MSR_VSX; break; > - } > + if (!(vcpu->arch.hflags & BOOK3S_HFLAG_PAIRED_SINGLE)) { > + /* Do paired single emulation */ > + > + switch (exit_nr) { > + case BOOK3S_INTERRUPT_FP_UNAVAIL: > + ext_msr = MSR_FP; > + break; > + > + case BOOK3S_INTERRUPT_ALTIVEC: > + ext_msr = MSR_VEC; > + break; > + > + case BOOK3S_INTERRUPT_VSX: > + ext_msr = MSR_VSX; > + break; > + } > > - switch (kvmppc_check_ext(vcpu, exit_nr)) { > - case EMULATE_DONE: > - /* everything ok - let's enable the ext */ > r = kvmppc_handle_ext(vcpu, exit_nr, ext_msr); > break; > - case EMULATE_FAIL: > + } > + > + emul = kvmppc_get_last_inst(vcpu, false, &last_inst); > + if (emul == EMULATE_DONE) { > /* we need to emulate this instruction */ > goto program_interrupt; > break; > - default: > - /* nothing to worry about - go again */ > - break; > + } else { > + r = RESUME_GUEST; > } > + > break; > } > case BOOK3S_INTERRUPT_ALIGNMENT: > - if (kvmppc_read_inst(vcpu) == EMULATE_DONE) { Phew - this removes the ability to inject an instruction page fault on this path. It's probably ok to do so, but please eliminate kvmppc_read_inst() in a separate patch before this one so we can later bisect it more easily when it fails. Alex > - u32 last_inst = kvmppc_get_last_inst(vcpu); > + { > + u32 last_inst; > + int emul = kvmppc_get_last_inst(vcpu, false, &last_inst); > + > + if (emul == EMULATE_DONE) { > u32 dsisr; > u64 dar; > > @@ -1110,6 +1117,7 @@ program_interrupt: > } > r = RESUME_GUEST; > break; > + } > #ifdef CONFIG_PPC_BOOK3S_64 > case BOOK3S_INTERRUPT_FAC_UNAVAIL: > kvmppc_handle_fac(vcpu, vcpu->arch.shadow_fscr >> 56); > diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c > index ab62109..34a42b9 100644 > --- a/arch/powerpc/kvm/booke.c > +++ b/arch/powerpc/kvm/booke.c > @@ -752,6 +752,9 @@ static int emulation_exit(struct kvm_run *run, struct kvm_vcpu *vcpu) > * they were actually modified by emulation. */ > return RESUME_GUEST_NV; > > + case EMULATE_AGAIN: > + return RESUME_GUEST; > + > case EMULATE_DO_DCR: > run->exit_reason = KVM_EXIT_DCR; > return RESUME_HOST; > diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c > index dd2cc03..f692c12 100644 > --- a/arch/powerpc/kvm/e500_mmu_host.c > +++ b/arch/powerpc/kvm/e500_mmu_host.c > @@ -606,6 +606,11 @@ void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 eaddr, gpa_t gpaddr, > } > } > > +int kvmppc_load_last_inst(struct kvm_vcpu *vcpu, bool prev, u32 *instr) > +{ > + return EMULATE_FAIL; > +} > + > /************* MMU Notifiers *************/ > > int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) > diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c > index da86d9b..c5c64b6 100644 > --- a/arch/powerpc/kvm/emulate.c > +++ b/arch/powerpc/kvm/emulate.c > @@ -224,19 +224,25 @@ static int kvmppc_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, int rt) > * from opcode tables in the future. */ > int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu) > { > - u32 inst = kvmppc_get_last_inst(vcpu); > - int ra = get_ra(inst); > - int rs = get_rs(inst); > - int rt = get_rt(inst); > - int sprn = get_sprn(inst); > - enum emulation_result emulated = EMULATE_DONE; > + u32 inst; > + int ra, rs, rt, sprn; > + enum emulation_result emulated; > int advance = 1; > > /* this default type might be overwritten by subcategories */ > kvmppc_set_exit_type(vcpu, EMULATED_INST_EXITS); > > + emulated = kvmppc_get_last_inst(vcpu, false, &inst); > + if (emulated != EMULATE_DONE) > + return emulated; > + > pr_debug("Emulating opcode %d / %d\n", get_op(inst), get_xop(inst)); > > + ra = get_ra(inst); > + rs = get_rs(inst); > + rt = get_rt(inst); > + sprn = get_sprn(inst); > + > switch (get_op(inst)) { > case OP_TRAP: > #ifdef CONFIG_PPC_BOOK3S > diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c > index bab20f4..1dba84b 100644 > --- a/arch/powerpc/kvm/powerpc.c > +++ b/arch/powerpc/kvm/powerpc.c > @@ -261,6 +261,9 @@ int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu) > * actually modified. */ > r = RESUME_GUEST_NV; > break; > + case EMULATE_AGAIN: > + r = RESUME_GUEST; > + break; > case EMULATE_DO_MMIO: > run->exit_reason = KVM_EXIT_MMIO; > /* We must reload nonvolatiles because "update" load/store > @@ -270,11 +273,14 @@ int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu) > r = RESUME_HOST_NV; > break; > case EMULATE_FAIL: > + { > + u32 last_inst; > + kvmppc_get_last_inst(vcpu, false, &last_inst); > /* XXX Deliver Program interrupt to guest. */ > - printk(KERN_EMERG "%s: emulation failed (%08x)\n", __func__, > - kvmppc_get_last_inst(vcpu)); > + pr_emerg("%s: emulation failed (%08x)\n", __func__, last_inst); > r = RESUME_HOST; > break; > + } > default: > WARN_ON(1); > r = RESUME_GUEST; -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h index f52f656..3409572 100644 --- a/arch/powerpc/include/asm/kvm_book3s.h +++ b/arch/powerpc/include/asm/kvm_book3s.h @@ -274,30 +274,14 @@ static inline bool kvmppc_need_byteswap(struct kvm_vcpu *vcpu) return (kvmppc_get_msr(vcpu) & MSR_LE) != (MSR_KERNEL & MSR_LE); } -static inline u32 kvmppc_get_last_inst_internal(struct kvm_vcpu *vcpu, ulong pc) +static inline int kvmppc_load_last_inst(struct kvm_vcpu *vcpu, bool prev, + u32 *inst) { - /* Load the instruction manually if it failed to do so in the - * exit path */ - if (vcpu->arch.last_inst == KVM_INST_FETCH_FAILED) - kvmppc_ld(vcpu, &pc, sizeof(u32), &vcpu->arch.last_inst, false); + ulong pc = kvmppc_get_pc(vcpu); - return kvmppc_need_byteswap(vcpu) ? swab32(vcpu->arch.last_inst) : - vcpu->arch.last_inst; -} - -static inline u32 kvmppc_get_last_inst(struct kvm_vcpu *vcpu) -{ - return kvmppc_get_last_inst_internal(vcpu, kvmppc_get_pc(vcpu)); -} - -/* - * Like kvmppc_get_last_inst(), but for fetching a sc instruction. - * Because the sc instruction sets SRR0 to point to the following - * instruction, we have to fetch from pc - 4. - */ -static inline u32 kvmppc_get_last_sc(struct kvm_vcpu *vcpu) -{ - return kvmppc_get_last_inst_internal(vcpu, kvmppc_get_pc(vcpu) - 4); + if (prev) + pc -= 4; + return kvmppc_ld(vcpu, &pc, sizeof(u32), &vcpu->arch.last_inst, false); } static inline ulong kvmppc_get_fault_dar(struct kvm_vcpu *vcpu) diff --git a/arch/powerpc/include/asm/kvm_booke.h b/arch/powerpc/include/asm/kvm_booke.h index c7aed61..1e28371 100644 --- a/arch/powerpc/include/asm/kvm_booke.h +++ b/arch/powerpc/include/asm/kvm_booke.h @@ -33,6 +33,8 @@ #define KVMPPC_INST_EHPRIV_DEBUG (KVMPPC_INST_EHPRIV | \ (EHPRIV_OC_DEBUG << EHPRIV_OC_SHIFT)) +extern int kvmppc_load_last_inst(struct kvm_vcpu *vcpu, bool prev, u32 *inst); + static inline void kvmppc_set_gpr(struct kvm_vcpu *vcpu, int num, ulong val) { vcpu->arch.gpr[num] = val; @@ -69,11 +71,6 @@ static inline bool kvmppc_need_byteswap(struct kvm_vcpu *vcpu) return false; } -static inline u32 kvmppc_get_last_inst(struct kvm_vcpu *vcpu) -{ - return vcpu->arch.last_inst; -} - static inline void kvmppc_set_ctr(struct kvm_vcpu *vcpu, ulong val) { vcpu->arch.ctr = val; diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h index 4a7cc45..619be2f 100644 --- a/arch/powerpc/include/asm/kvm_ppc.h +++ b/arch/powerpc/include/asm/kvm_ppc.h @@ -234,6 +234,22 @@ struct kvmppc_ops { extern struct kvmppc_ops *kvmppc_hv_ops; extern struct kvmppc_ops *kvmppc_pr_ops; +static inline int kvmppc_get_last_inst(struct kvm_vcpu *vcpu, bool prev, + u32 *inst) +{ + int ret = EMULATE_DONE; + + /* Load the instruction manually if it failed to do so in the + * exit path */ + if (vcpu->arch.last_inst == KVM_INST_FETCH_FAILED) + ret = kvmppc_load_last_inst(vcpu, prev, &vcpu->arch.last_inst); + + *inst = kvmppc_need_byteswap(vcpu) ? swab32(vcpu->arch.last_inst) : + vcpu->arch.last_inst; + + return ret; +} + static inline bool is_kvmppc_hv_enabled(struct kvm *kvm) { return kvm->arch.kvm_ops == kvmppc_hv_ops; diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index 8056107..2ffb3dd 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -530,21 +530,13 @@ static int instruction_is_store(unsigned int instr) static int kvmppc_hv_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu, unsigned long gpa, gva_t ea, int is_store) { - int ret; u32 last_inst; - unsigned long srr0 = kvmppc_get_pc(vcpu); - /* We try to load the last instruction. We don't let - * emulate_instruction do it as it doesn't check what - * kvmppc_ld returns. + /* * If we fail, we just return to the guest and try executing it again. */ - if (vcpu->arch.last_inst == KVM_INST_FETCH_FAILED) { - ret = kvmppc_ld(vcpu, &srr0, sizeof(u32), &last_inst, false); - if (ret != EMULATE_DONE || last_inst == KVM_INST_FETCH_FAILED) - return RESUME_GUEST; - vcpu->arch.last_inst = last_inst; - } + if (kvmppc_get_last_inst(vcpu, false, &last_inst) != EMULATE_DONE) + return RESUME_GUEST; /* * WARNING: We do not know for sure whether the instruction we just @@ -558,7 +550,7 @@ static int kvmppc_hv_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu, * we just return and retry the instruction. */ - if (instruction_is_store(kvmppc_get_last_inst(vcpu)) != !!is_store) + if (instruction_is_store(last_inst) != !!is_store) return RESUME_GUEST; /* diff --git a/arch/powerpc/kvm/book3s_paired_singles.c b/arch/powerpc/kvm/book3s_paired_singles.c index 6c8011f..6362ad4 100644 --- a/arch/powerpc/kvm/book3s_paired_singles.c +++ b/arch/powerpc/kvm/book3s_paired_singles.c @@ -639,26 +639,36 @@ static int kvmppc_ps_one_in(struct kvm_vcpu *vcpu, bool rc, int kvmppc_emulate_paired_single(struct kvm_run *run, struct kvm_vcpu *vcpu) { - u32 inst = kvmppc_get_last_inst(vcpu); + u32 inst; enum emulation_result emulated = EMULATE_DONE; + int ax_rd, ax_ra, ax_rb, ax_rc; + short full_d; + u64 *fpr_d, *fpr_a, *fpr_b, *fpr_c; - int ax_rd = inst_get_field(inst, 6, 10); - int ax_ra = inst_get_field(inst, 11, 15); - int ax_rb = inst_get_field(inst, 16, 20); - int ax_rc = inst_get_field(inst, 21, 25); - short full_d = inst_get_field(inst, 16, 31); - - u64 *fpr_d = &VCPU_FPR(vcpu, ax_rd); - u64 *fpr_a = &VCPU_FPR(vcpu, ax_ra); - u64 *fpr_b = &VCPU_FPR(vcpu, ax_rb); - u64 *fpr_c = &VCPU_FPR(vcpu, ax_rc); - - bool rcomp = (inst & 1) ? true : false; - u32 cr = kvmppc_get_cr(vcpu); + bool rcomp; + u32 cr; #ifdef DEBUG int i; #endif + emulated = kvmppc_get_last_inst(vcpu, false, &inst); + if (emulated != EMULATE_DONE) + return emulated; + + ax_rd = inst_get_field(inst, 6, 10); + ax_ra = inst_get_field(inst, 11, 15); + ax_rb = inst_get_field(inst, 16, 20); + ax_rc = inst_get_field(inst, 21, 25); + full_d = inst_get_field(inst, 16, 31); + + fpr_d = &VCPU_FPR(vcpu, ax_rd); + fpr_a = &VCPU_FPR(vcpu, ax_ra); + fpr_b = &VCPU_FPR(vcpu, ax_rb); + fpr_c = &VCPU_FPR(vcpu, ax_rc); + + rcomp = (inst & 1) ? true : false; + cr = kvmppc_get_cr(vcpu); + if (!kvmppc_inst_is_paired_single(vcpu, inst)) return EMULATE_FAIL; diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index 23367a7..48b633c 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -637,42 +637,6 @@ static void kvmppc_giveup_fac(struct kvm_vcpu *vcpu, ulong fac) #endif } -static int kvmppc_read_inst(struct kvm_vcpu *vcpu) -{ - ulong srr0 = kvmppc_get_pc(vcpu); - u32 last_inst = kvmppc_get_last_inst(vcpu); - int ret; - - ret = kvmppc_ld(vcpu, &srr0, sizeof(u32), &last_inst, false); - if (ret == -ENOENT) { - ulong msr = kvmppc_get_msr(vcpu); - - msr = kvmppc_set_field(msr, 33, 33, 1); - msr = kvmppc_set_field(msr, 34, 36, 0); - msr = kvmppc_set_field(msr, 42, 47, 0); - kvmppc_set_msr_fast(vcpu, msr); - kvmppc_book3s_queue_irqprio(vcpu, BOOK3S_INTERRUPT_INST_STORAGE); - return EMULATE_AGAIN; - } - - return EMULATE_DONE; -} - -static int kvmppc_check_ext(struct kvm_vcpu *vcpu, unsigned int exit_nr) -{ - - /* Need to do paired single emulation? */ - if (!(vcpu->arch.hflags & BOOK3S_HFLAG_PAIRED_SINGLE)) - return EMULATE_DONE; - - /* Read out the instruction */ - if (kvmppc_read_inst(vcpu) == EMULATE_DONE) - /* Need to emulate */ - return EMULATE_FAIL; - - return EMULATE_AGAIN; -} - /* Handle external providers (FPU, Altivec, VSX) */ static int kvmppc_handle_ext(struct kvm_vcpu *vcpu, unsigned int exit_nr, ulong msr) @@ -977,15 +941,24 @@ int kvmppc_handle_exit_pr(struct kvm_run *run, struct kvm_vcpu *vcpu, { enum emulation_result er; ulong flags; + u32 last_inst; + int emul; program_interrupt: flags = vcpu->arch.shadow_srr1 & 0x1f0000ull; + emul = kvmppc_get_last_inst(vcpu, false, &last_inst); + if (emul != EMULATE_DONE) { + r = RESUME_GUEST; + break; + } + if (kvmppc_get_msr(vcpu) & MSR_PR) { #ifdef EXIT_DEBUG - printk(KERN_INFO "Userspace triggered 0x700 exception at 0x%lx (0x%x)\n", kvmppc_get_pc(vcpu), kvmppc_get_last_inst(vcpu)); + pr_info("Userspace triggered 0x700 exception at\n" + "0x%lx (0x%x)\n", kvmppc_get_pc(vcpu), last_inst); #endif - if ((kvmppc_get_last_inst(vcpu) & 0xff0007ff) != + if ((last_inst & 0xff0007ff) != (INS_DCBZ & 0xfffffff7)) { kvmppc_core_queue_program(vcpu, flags); r = RESUME_GUEST; @@ -1004,7 +977,7 @@ program_interrupt: break; case EMULATE_FAIL: printk(KERN_CRIT "%s: emulation at %lx failed (%08x)\n", - __func__, kvmppc_get_pc(vcpu), kvmppc_get_last_inst(vcpu)); + __func__, kvmppc_get_pc(vcpu), last_inst); kvmppc_core_queue_program(vcpu, flags); r = RESUME_GUEST; break; @@ -1021,8 +994,25 @@ program_interrupt: break; } case BOOK3S_INTERRUPT_SYSCALL: + { + u32 last_sc; + int emul; + + /* Get last sc for papr */ + if (vcpu->arch.papr_enabled) { + /* + * The sc instuction sets SRR0 to point to the next inst + */ + emul = kvmppc_get_last_inst(vcpu, true, &last_sc); + if (emul != EMULATE_DONE) { + kvmppc_set_pc(vcpu, kvmppc_get_pc(vcpu) - 4); + r = RESUME_GUEST; + break; + } + } + if (vcpu->arch.papr_enabled && - (kvmppc_get_last_sc(vcpu) == 0x44000022) && + (last_sc == 0x44000022) && !(kvmppc_get_msr(vcpu) & MSR_PR)) { /* SC 1 papr hypercalls */ ulong cmd = kvmppc_get_gpr(vcpu, 3); @@ -1067,36 +1057,53 @@ program_interrupt: r = RESUME_GUEST; } break; + } case BOOK3S_INTERRUPT_FP_UNAVAIL: case BOOK3S_INTERRUPT_ALTIVEC: case BOOK3S_INTERRUPT_VSX: { int ext_msr = 0; + int emul; + u32 last_inst; - switch (exit_nr) { - case BOOK3S_INTERRUPT_FP_UNAVAIL: ext_msr = MSR_FP; break; - case BOOK3S_INTERRUPT_ALTIVEC: ext_msr = MSR_VEC; break; - case BOOK3S_INTERRUPT_VSX: ext_msr = MSR_VSX; break; - } + if (!(vcpu->arch.hflags & BOOK3S_HFLAG_PAIRED_SINGLE)) { + /* Do paired single emulation */ + + switch (exit_nr) { + case BOOK3S_INTERRUPT_FP_UNAVAIL: + ext_msr = MSR_FP; + break; + + case BOOK3S_INTERRUPT_ALTIVEC: + ext_msr = MSR_VEC; + break; + + case BOOK3S_INTERRUPT_VSX: + ext_msr = MSR_VSX; + break; + } - switch (kvmppc_check_ext(vcpu, exit_nr)) { - case EMULATE_DONE: - /* everything ok - let's enable the ext */ r = kvmppc_handle_ext(vcpu, exit_nr, ext_msr); break; - case EMULATE_FAIL: + } + + emul = kvmppc_get_last_inst(vcpu, false, &last_inst); + if (emul == EMULATE_DONE) { /* we need to emulate this instruction */ goto program_interrupt; break; - default: - /* nothing to worry about - go again */ - break; + } else { + r = RESUME_GUEST; } + break; } case BOOK3S_INTERRUPT_ALIGNMENT: - if (kvmppc_read_inst(vcpu) == EMULATE_DONE) { - u32 last_inst = kvmppc_get_last_inst(vcpu); + { + u32 last_inst; + int emul = kvmppc_get_last_inst(vcpu, false, &last_inst); + + if (emul == EMULATE_DONE) { u32 dsisr; u64 dar; @@ -1110,6 +1117,7 @@ program_interrupt: } r = RESUME_GUEST; break; + } #ifdef CONFIG_PPC_BOOK3S_64 case BOOK3S_INTERRUPT_FAC_UNAVAIL: kvmppc_handle_fac(vcpu, vcpu->arch.shadow_fscr >> 56); diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index ab62109..34a42b9 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -752,6 +752,9 @@ static int emulation_exit(struct kvm_run *run, struct kvm_vcpu *vcpu) * they were actually modified by emulation. */ return RESUME_GUEST_NV; + case EMULATE_AGAIN: + return RESUME_GUEST; + case EMULATE_DO_DCR: run->exit_reason = KVM_EXIT_DCR; return RESUME_HOST; diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c index dd2cc03..f692c12 100644 --- a/arch/powerpc/kvm/e500_mmu_host.c +++ b/arch/powerpc/kvm/e500_mmu_host.c @@ -606,6 +606,11 @@ void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 eaddr, gpa_t gpaddr, } } +int kvmppc_load_last_inst(struct kvm_vcpu *vcpu, bool prev, u32 *instr) +{ + return EMULATE_FAIL; +} + /************* MMU Notifiers *************/ int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c index da86d9b..c5c64b6 100644 --- a/arch/powerpc/kvm/emulate.c +++ b/arch/powerpc/kvm/emulate.c @@ -224,19 +224,25 @@ static int kvmppc_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, int rt) * from opcode tables in the future. */ int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu) { - u32 inst = kvmppc_get_last_inst(vcpu); - int ra = get_ra(inst); - int rs = get_rs(inst); - int rt = get_rt(inst); - int sprn = get_sprn(inst); - enum emulation_result emulated = EMULATE_DONE; + u32 inst; + int ra, rs, rt, sprn; + enum emulation_result emulated; int advance = 1; /* this default type might be overwritten by subcategories */ kvmppc_set_exit_type(vcpu, EMULATED_INST_EXITS); + emulated = kvmppc_get_last_inst(vcpu, false, &inst); + if (emulated != EMULATE_DONE) + return emulated; + pr_debug("Emulating opcode %d / %d\n", get_op(inst), get_xop(inst)); + ra = get_ra(inst); + rs = get_rs(inst); + rt = get_rt(inst); + sprn = get_sprn(inst); + switch (get_op(inst)) { case OP_TRAP: #ifdef CONFIG_PPC_BOOK3S diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index bab20f4..1dba84b 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -261,6 +261,9 @@ int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu) * actually modified. */ r = RESUME_GUEST_NV; break; + case EMULATE_AGAIN: + r = RESUME_GUEST; + break; case EMULATE_DO_MMIO: run->exit_reason = KVM_EXIT_MMIO; /* We must reload nonvolatiles because "update" load/store @@ -270,11 +273,14 @@ int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu) r = RESUME_HOST_NV; break; case EMULATE_FAIL: + { + u32 last_inst; + kvmppc_get_last_inst(vcpu, false, &last_inst); /* XXX Deliver Program interrupt to guest. */ - printk(KERN_EMERG "%s: emulation failed (%08x)\n", __func__, - kvmppc_get_last_inst(vcpu)); + pr_emerg("%s: emulation failed (%08x)\n", __func__, last_inst); r = RESUME_HOST; break; + } default: WARN_ON(1); r = RESUME_GUEST;
On book3e, guest last instruction is read on the exit path using load external pid (lwepx) dedicated instruction. This load operation may fail due to TLB eviction and execute-but-not-read entries. This patch lay down the path for an alternative solution to read the guest last instruction, by allowing kvmppc_get_lat_inst() function to fail. Architecture specific implmentations of kvmppc_load_last_inst() may read last guest instruction and instruct the emulation layer to re-execute the guest in case of failure. Make kvmppc_get_last_inst() definition common between architectures. Signed-off-by: Mihai Caraman <mihai.caraman@freescale.com> --- v3: - these changes compile on book3s, please validate the functionality and do the necessary adaptations! - rework patch description - add common definition for kvmppc_get_last_inst() - check return values in book3s code v2: - integrated kvmppc_get_last_inst() in book3s code and checked build - addressed cosmetic feedback arch/powerpc/include/asm/kvm_book3s.h | 28 ++------ arch/powerpc/include/asm/kvm_booke.h | 7 +- arch/powerpc/include/asm/kvm_ppc.h | 16 +++++ arch/powerpc/kvm/book3s_64_mmu_hv.c | 16 ++--- arch/powerpc/kvm/book3s_paired_singles.c | 38 ++++++---- arch/powerpc/kvm/book3s_pr.c | 116 +++++++++++++++++-------------- arch/powerpc/kvm/booke.c | 3 + arch/powerpc/kvm/e500_mmu_host.c | 5 ++ arch/powerpc/kvm/emulate.c | 18 +++-- arch/powerpc/kvm/powerpc.c | 10 ++- 10 files changed, 142 insertions(+), 115 deletions(-)