/* * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License, version 2, as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * * Copyright 2010 Paul Mackerras, IBM Corp. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* POWER7 has 10-bit LPIDs, PPC970 has 6-bit LPIDs */ #define MAX_LPID_970 63 /* Power architecture requires HPT is at least 256kB */ #define PPC_MIN_HPT_ORDER 18 static long kvmppc_virtmode_do_h_enter(struct kvm *kvm, unsigned long flags, long pte_index, unsigned long pteh, unsigned long ptel, unsigned long *pte_idx_ret); static void kvmppc_rmap_reset(struct kvm *kvm); long kvmppc_alloc_hpt(struct kvm *kvm, u32 *htab_orderp) { unsigned long hpt; struct revmap_entry *rev; struct kvmppc_linear_info *li; long order = kvm_hpt_order; if (htab_orderp) { order = *htab_orderp; if (order < PPC_MIN_HPT_ORDER) order = PPC_MIN_HPT_ORDER; } /* * If the user wants a different size from default, * try first to allocate it from the kernel page allocator. */ hpt = 0; if (order != kvm_hpt_order) { hpt = __get_free_pages(GFP_KERNEL|__GFP_ZERO|__GFP_REPEAT| __GFP_NOWARN, order - PAGE_SHIFT); if (!hpt) --order; } /* Next try to allocate from the preallocated pool */ if (!hpt) { li = kvm_alloc_hpt(); if (li) { hpt = (ulong)li->base_virt; kvm->arch.hpt_li = li; order = kvm_hpt_order; } } /* Lastly try successively smaller sizes from the page allocator */ while (!hpt && order > PPC_MIN_HPT_ORDER) { hpt = __get_free_pages(GFP_KERNEL|__GFP_ZERO|__GFP_REPEAT| __GFP_NOWARN, order - PAGE_SHIFT); if (!hpt) --order; } if (!hpt) return -ENOMEM; kvm->arch.hpt_virt = hpt; kvm->arch.hpt_order = order; /* HPTEs are 2**4 bytes long */ kvm->arch.hpt_npte = 1ul << (order - 4); /* 128 (2**7) bytes in each HPTEG */ kvm->arch.hpt_mask = (1ul << (order - 7)) - 1; /* Allocate reverse map array */ rev = vmalloc(sizeof(struct revmap_entry) * kvm->arch.hpt_npte); if (!rev) { pr_err("kvmppc_alloc_hpt: Couldn't alloc reverse map array\n"); goto out_freehpt; } kvm->arch.revmap = rev; kvm->arch.sdr1 = __pa(hpt) | (order - 18); pr_info("KVM guest htab at %lx (order %ld), LPID %x\n", hpt, order, kvm->arch.lpid); if (htab_orderp) *htab_orderp = order; return 0; out_freehpt: if (kvm->arch.hpt_li) kvm_release_hpt(kvm->arch.hpt_li); else free_pages(hpt, order - PAGE_SHIFT); return -ENOMEM; } long kvmppc_alloc_reset_hpt(struct kvm *kvm, u32 *htab_orderp) { long err = -EBUSY; long order; mutex_lock(&kvm->lock); if (kvm->arch.rma_setup_done) { kvm->arch.rma_setup_done = 0; /* order rma_setup_done vs. vcpus_running */ smp_mb(); if (atomic_read(&kvm->arch.vcpus_running)) { kvm->arch.rma_setup_done = 1; goto out; } } if (kvm->arch.hpt_virt) { order = kvm->arch.hpt_order; /* Set the entire HPT to 0, i.e. invalid HPTEs */ memset((void *)kvm->arch.hpt_virt, 0, 1ul << order); /* * Reset all the reverse-mapping chains for all memslots */ kvmppc_rmap_reset(kvm); /* Ensure that each vcpu will flush its TLB on next entry. */ cpumask_setall(&kvm->arch.need_tlb_flush); *htab_orderp = order; err = 0; } else { err = kvmppc_alloc_hpt(kvm, htab_orderp); order = *htab_orderp; } out: mutex_unlock(&kvm->lock); return err; } void kvmppc_free_hpt(struct kvm *kvm) { kvmppc_free_lpid(kvm->arch.lpid); vfree(kvm->arch.revmap); if (kvm->arch.hpt_li) kvm_release_hpt(kvm->arch.hpt_li); else free_pages(kvm->arch.hpt_virt, kvm->arch.hpt_order - PAGE_SHIFT); } /* Bits in first HPTE dword for pagesize 4k, 64k or 16M */ static inline unsigned long hpte0_pgsize_encoding(unsigned long pgsize) { return (pgsize > 0x1000) ? HPTE_V_LARGE : 0; } /* Bits in second HPTE dword for pagesize 4k, 64k or 16M */ static inline unsigned long hpte1_pgsize_encoding(unsigned long pgsize) { return (pgsize == 0x10000) ? 0x1000 : 0; } void kvmppc_map_vrma(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot, unsigned long porder) { unsigned long i; unsigned long npages; unsigned long hp_v, hp_r; unsigned long addr, hash; unsigned long psize; unsigned long hp0, hp1; unsigned long idx_ret; long ret; struct kvm *kvm = vcpu->kvm; psize = 1ul << porder; npages = memslot->npages >> (porder - PAGE_SHIFT); /* VRMA can't be > 1TB */ if (npages > 1ul << (40 - porder)) npages = 1ul << (40 - porder); /* Can't use more than 1 HPTE per HPTEG */ if (npages > kvm->arch.hpt_mask + 1) npages = kvm->arch.hpt_mask + 1; hp0 = HPTE_V_1TB_SEG | (VRMA_VSID << (40 - 16)) | HPTE_V_BOLTED | hpte0_pgsize_encoding(psize); hp1 = hpte1_pgsize_encoding(psize) | HPTE_R_R | HPTE_R_C | HPTE_R_M | PP_RWXX; for (i = 0; i < npages; ++i) { addr = i << porder; /* can't use hpt_hash since va > 64 bits */ hash = (i ^ (VRMA_VSID ^ (VRMA_VSID << 25))) & kvm->arch.hpt_mask; /* * We assume that the hash table is empty and no * vcpus are using it at this stage. Since we create * at most one HPTE per HPTEG, we just assume entry 7 * is available and use it. */ hash = (hash << 3) + 7; hp_v = hp0 | ((addr >> 16) & ~0x7fUL); hp_r = hp1 | addr; ret = kvmppc_virtmode_do_h_enter(kvm, H_EXACT, hash, hp_v, hp_r, &idx_ret); if (ret != H_SUCCESS) { pr_err("KVM: map_vrma at %lx failed, ret=%ld\n", addr, ret); break; } } } int kvmppc_mmu_hv_init(void) { unsigned long host_lpid, rsvd_lpid; if (!cpu_has_feature(CPU_FTR_HVMODE)) return -EINVAL; /* POWER7 has 10-bit LPIDs, PPC970 and e500mc have 6-bit LPIDs */ if (cpu_has_feature(CPU_FTR_ARCH_206)) { host_lpid = mfspr(SPRN_LPID); /* POWER7 */ rsvd_lpid = LPID_RSVD; } else { host_lpid = 0; /* PPC970 */ rsvd_lpid = MAX_LPID_970; } kvmppc_init_lpid(rsvd_lpid + 1); kvmppc_claim_lpid(host_lpid); /* rsvd_lpid is reserved for use in partition switching */ kvmppc_claim_lpid(rsvd_lpid); return 0; } void kvmppc_mmu_destroy(struct kvm_vcpu *vcpu) { } static void kvmppc_mmu_book3s_64_hv_reset_msr(struct kvm_vcpu *vcpu) { kvmppc_set_msr(vcpu, MSR_SF | MSR_ME); } /* * This is called to get a reference to a guest page if there isn't * one already in the memslot->arch.slot_phys[] array. */ static long kvmppc_get_guest_page(struct kvm *kvm, unsigned long gfn, struct kvm_memory_slot *memslot, unsigned long psize) { unsigned long start; long np, err; struct page *page, *hpage, *pages[1]; unsigned long s, pgsize; unsigned long *physp; unsigned int is_io, got, pgorder; struct vm_area_struct *vma; unsigned long pfn, i, npages; physp = memslot->arch.slot_phys; if (!physp) return -EINVAL; if (physp[gfn - memslot->base_gfn]) return 0; is_io = 0; got = 0; page = NULL; pgsize = psize; err = -EINVAL; start = gfn_to_hva_memslot(memslot, gfn); /* Instantiate and get the page we want access to */ np = get_user_pages_fast(start, 1, 1, pages); if (np != 1) { /* Look up the vma for the page */ down_read(¤t->mm->mmap_sem); vma = find_vma(current->mm, start); if (!vma || vma->vm_start > start || start + psize > vma->vm_end || !(vma->vm_flags & VM_PFNMAP)) goto up_err; is_io = hpte_cache_bits(pgprot_val(vma->vm_page_prot)); pfn = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT); /* check alignment of pfn vs. requested page size */ if (psize > PAGE_SIZE && (pfn & ((psize >> PAGE_SHIFT) - 1))) goto up_err; up_read(¤t->mm->mmap_sem); } else { page = pages[0]; got = KVMPPC_GOT_PAGE; /* See if this is a large page */ s = PAGE_SIZE; if (PageHuge(page)) { hpage = compound_head(page); s <<= compound_order(hpage); /* Get the whole large page if slot alignment is ok */ if (s > psize && slot_is_aligned(memslot, s) && !(memslot->userspace_addr & (s - 1))) { start &= ~(s - 1); pgsize = s; get_page(hpage); put_page(page); page = hpage; } } if (s < psize) goto out; pfn = page_to_pfn(page); } npages = pgsize >> PAGE_SHIFT; pgorder = __ilog2(npages); physp += (gfn - memslot->base_gfn) & ~(npages - 1); spin_lock(&kvm->arch.slot_phys_lock); for (i = 0; i < npages; ++i) { if (!physp[i]) { physp[i] = ((pfn + i) << PAGE_SHIFT) + got + is_io + pgorder; got = 0; } } spin_unlock(&kvm->arch.slot_phys_lock); err = 0; out: if (got) put_page(page); return err; up_err: up_read(¤t->mm->mmap_sem); return err; } long kvmppc_virtmode_do_h_enter(struct kvm *kvm, unsigned long flags, long pte_index, unsigned long pteh, unsigned long ptel, unsigned long *pte_idx_ret) { unsigned long psize, gpa, gfn; struct kvm_memory_slot *memslot; long ret; if (kvm->arch.using_mmu_notifiers) goto do_insert; psize = hpte_page_size(pteh, ptel); if (!psize) return H_PARAMETER; pteh &= ~(HPTE_V_HVLOCK | HPTE_V_ABSENT | HPTE_V_VALID); /* Find the memslot (if any) for this address */ gpa = (ptel & HPTE_R_RPN) & ~(psize - 1); gfn = gpa >> PAGE_SHIFT; memslot = gfn_to_memslot(kvm, gfn); if (memslot && !(memslot->flags & KVM_MEMSLOT_INVALID)) { if (!slot_is_aligned(memslot, psize)) return H_PARAMETER; if (kvmppc_get_guest_page(kvm, gfn, memslot, psize) < 0) return H_PARAMETER; } do_insert: /* Protect linux PTE lookup from page table destruction */ rcu_read_lock_sched(); /* this disables preemption too */ ret = kvmppc_do_h_enter(kvm, flags, pte_index, pteh, ptel, current->mm->pgd, false, pte_idx_ret); rcu_read_unlock_sched(); if (ret == H_TOO_HARD) { /* this can't happen */ pr_err("KVM: Oops, kvmppc_h_enter returned too hard!\n"); ret = H_RESOURCE; /* or something */ } return ret; } /* * We come here on a H_ENTER call from the guest when we are not * using mmu notifiers and we don't have the requested page pinned * already. */ long kvmppc_virtmode_h_enter(struct kvm_vcpu *vcpu, unsigned long flags, long pte_index, unsigned long pteh, unsigned long ptel) { return kvmppc_virtmode_do_h_enter(vcpu->kvm, flags, pte_index, pteh, ptel, &vcpu->arch.gpr[4]); } static struct kvmppc_slb *kvmppc_mmu_book3s_hv_find_slbe(struct kvm_vcpu *vcpu, gva_t eaddr) { u64 mask; int i; for (i = 0; i < vcpu->arch.slb_nr; i++) { if (!(vcpu->arch.slb[i].orige & SLB_ESID_V)) continue; if (vcpu->arch.slb[i].origv & SLB_VSID_B_1T) mask = ESID_MASK_1T; else mask = ESID_MASK; if (((vcpu->arch.slb[i].orige ^ eaddr) & mask) == 0) return &vcpu->arch.slb[i]; } return NULL; } static unsigned long kvmppc_mmu_get_real_addr(unsigned long v, unsigned long r, unsigned long ea) { unsigned long ra_mask; ra_mask = hpte_page_size(v, r) - 1; return (r & HPTE_R_RPN & ~ra_mask) | (ea & ra_mask); } static int kvmppc_mmu_book3s_64_hv_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, struct kvmppc_pte *gpte, bool data) { struct kvm *kvm = vcpu->kvm; struct kvmppc_slb *slbe; unsigned long slb_v; unsigned long pp, key; unsigned long v, gr; unsigned long *hptep; int index; int virtmode = vcpu->arch.shregs.msr & (data ? MSR_DR : MSR_IR); /* Get SLB entry */ if (virtmode) { slbe = kvmppc_mmu_book3s_hv_find_slbe(vcpu, eaddr); if (!slbe) return -EINVAL; slb_v = slbe->origv; } else { /* real mode access */ slb_v = vcpu->kvm->arch.vrma_slb_v; } /* Find the HPTE in the hash table */ index = kvmppc_hv_find_lock_hpte(kvm, eaddr, slb_v, HPTE_V_VALID | HPTE_V_ABSENT); if (index < 0) return -ENOENT; hptep = (unsigned long *)(kvm->arch.hpt_virt + (index << 4)); v = hptep[0] & ~HPTE_V_HVLOCK; gr = kvm->arch.revmap[index].guest_rpte; /* Unlock the HPTE */ asm volatile("lwsync" : : : "memory"); hptep[0] = v; gpte->eaddr = eaddr; gpte->vpage = ((v & HPTE_V_AVPN) << 4) | ((eaddr >> 12) & 0xfff); /* Get PP bits and key for permission check */ pp = gr & (HPTE_R_PP0 | HPTE_R_PP); key = (vcpu->arch.shregs.msr & MSR_PR) ? SLB_VSID_KP : SLB_VSID_KS; key &= slb_v; /* Calculate permissions */ gpte->may_read = hpte_read_permission(pp, key); gpte->may_write = hpte_write_permission(pp, key); gpte->may_execute = gpte->may_read && !(gr & (HPTE_R_N | HPTE_R_G)); /* Storage key permission check for POWER7 */ if (data && virtmode && cpu_has_feature(CPU_FTR_ARCH_206)) { int amrfield = hpte_get_skey_perm(gr, vcpu->arch.amr); if (amrfield & 1) gpte->may_read = 0; if (amrfield & 2) gpte->may_write = 0; } /* Get the guest physical address */ gpte->raddr = kvmppc_mmu_get_real_addr(v, gr, eaddr); return 0; } /* * Quick test for whether an instruction is a load or a store. * If the instruction is a load or a store, then this will indicate * which it is, at least on server processors. (Embedded processors * have some external PID instructions that don't follow the rule * embodied here.) If the instruction isn't a load or store, then * this doesn't return anything useful. */ static int instruction_is_store(unsigned int instr) { unsigned int mask; mask = 0x10000000; if ((instr & 0xfc000000) == 0x7c000000) mask = 0x100; /* major opcode 31 */ return (instr & mask) != 0; } 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; } /* * WARNING: We do not know for sure whether the instruction we just * read from memory is the same that caused the fault in the first * place. If the instruction we read is neither an load or a store, * then it can't access memory, so we don't need to worry about * enforcing access permissions. So, assuming it is a load or * store, we just check that its direction (load or store) is * consistent with the original fault, since that's what we * checked the access permissions against. If there is a mismatch * we just return and retry the instruction. */ if (instruction_is_store(vcpu->arch.last_inst) != !!is_store) return RESUME_GUEST; /* * Emulated accesses are emulated by looking at the hash for * translation once, then performing the access later. The * translation could be invalidated in the meantime in which * point performing the subsequent memory access on the old * physical address could possibly be a security hole for the * guest (but not the host). * * This is less of an issue for MMIO stores since they aren't * globally visible. It could be an issue for MMIO loads to * a certain extent but we'll ignore it for now. */ vcpu->arch.paddr_accessed = gpa; vcpu->arch.vaddr_accessed = ea; return kvmppc_emulate_mmio(run, vcpu); } int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, unsigned long ea, unsigned long dsisr) { struct kvm *kvm = vcpu->kvm; unsigned long *hptep, hpte[3], r; unsigned long mmu_seq, psize, pte_size; unsigned long gpa, gfn, hva, pfn; struct kvm_memory_slot *memslot; unsigned long *rmap; struct revmap_entry *rev; struct page *page, *pages[1]; long index, ret, npages; unsigned long is_io; unsigned int writing, write_ok; struct vm_area_struct *vma; unsigned long rcbits; /* * Real-mode code has already searched the HPT and found the * entry we're interested in. Lock the entry and check that * it hasn't changed. If it has, just return and re-execute the * instruction. */ if (ea != vcpu->arch.pgfault_addr) return RESUME_GUEST; index = vcpu->arch.pgfault_index; hptep = (unsigned long *)(kvm->arch.hpt_virt + (index << 4)); rev = &kvm->arch.revmap[index]; preempt_disable(); while (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) cpu_relax(); hpte[0] = hptep[0] & ~HPTE_V_HVLOCK; hpte[1] = hptep[1]; hpte[2] = r = rev->guest_rpte; asm volatile("lwsync" : : : "memory"); hptep[0] = hpte[0]; preempt_enable(); if (hpte[0] != vcpu->arch.pgfault_hpte[0] || hpte[1] != vcpu->arch.pgfault_hpte[1]) return RESUME_GUEST; /* Translate the logical address and get the page */ psize = hpte_page_size(hpte[0], r); gpa = (r & HPTE_R_RPN & ~(psize - 1)) | (ea & (psize - 1)); gfn = gpa >> PAGE_SHIFT; memslot = gfn_to_memslot(kvm, gfn); /* No memslot means it's an emulated MMIO region */ if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea, dsisr & DSISR_ISSTORE); if (!kvm->arch.using_mmu_notifiers) return -EFAULT; /* should never get here */ /* used to check for invalidations in progress */ mmu_seq = kvm->mmu_notifier_seq; smp_rmb(); is_io = 0; pfn = 0; page = NULL; pte_size = PAGE_SIZE; writing = (dsisr & DSISR_ISSTORE) != 0; /* If writing != 0, then the HPTE must allow writing, if we get here */ write_ok = writing; hva = gfn_to_hva_memslot(memslot, gfn); npages = get_user_pages_fast(hva, 1, writing, pages); if (npages < 1) { /* Check if it's an I/O mapping */ down_read(¤t->mm->mmap_sem); vma = find_vma(current->mm, hva); if (vma && vma->vm_start <= hva && hva + psize <= vma->vm_end && (vma->vm_flags & VM_PFNMAP)) { pfn = vma->vm_pgoff + ((hva - vma->vm_start) >> PAGE_SHIFT); pte_size = psize; is_io = hpte_cache_bits(pgprot_val(vma->vm_page_prot)); write_ok = vma->vm_flags & VM_WRITE; } up_read(¤t->mm->mmap_sem); if (!pfn) return -EFAULT; } else { page = pages[0]; if (PageHuge(page)) { page = compound_head(page); pte_size <<= compound_order(page); } /* if the guest wants write access, see if that is OK */ if (!writing && hpte_is_writable(r)) { pte_t *ptep, pte; /* * We need to protect against page table destruction * while looking up and updating the pte. */ rcu_read_lock_sched(); ptep = find_linux_pte_or_hugepte(current->mm->pgd, hva, NULL); if (ptep && pte_present(*ptep)) { pte = kvmppc_read_update_linux_pte(ptep, 1); if (pte_write(pte)) write_ok = 1; } rcu_read_unlock_sched(); } pfn = page_to_pfn(page); } ret = -EFAULT; if (psize > pte_size) goto out_put; /* Check WIMG vs. the actual page we're accessing */ if (!hpte_cache_flags_ok(r, is_io)) { if (is_io) return -EFAULT; /* * Allow guest to map emulated device memory as * uncacheable, but actually make it cacheable. */ r = (r & ~(HPTE_R_W|HPTE_R_I|HPTE_R_G)) | HPTE_R_M; } /* Set the HPTE to point to pfn */ r = (r & ~(HPTE_R_PP0 - pte_size)) | (pfn << PAGE_SHIFT); if (hpte_is_writable(r) && !write_ok) r = hpte_make_readonly(r); ret = RESUME_GUEST; preempt_disable(); while (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) cpu_relax(); if ((hptep[0] & ~HPTE_V_HVLOCK) != hpte[0] || hptep[1] != hpte[1] || rev->guest_rpte != hpte[2]) /* HPTE has been changed under us; let the guest retry */ goto out_unlock; hpte[0] = (hpte[0] & ~HPTE_V_ABSENT) | HPTE_V_VALID; rmap = &memslot->arch.rmap[gfn - memslot->base_gfn]; lock_rmap(rmap); /* Check if we might have been invalidated; let the guest retry if so */ ret = RESUME_GUEST; if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) { unlock_rmap(rmap); goto out_unlock; } /* Only set R/C in real HPTE if set in both *rmap and guest_rpte */ rcbits = *rmap >> KVMPPC_RMAP_RC_SHIFT; r &= rcbits | ~(HPTE_R_R | HPTE_R_C); if (hptep[0] & HPTE_V_VALID) { /* HPTE was previously valid, so we need to invalidate it */ unlock_rmap(rmap); hptep[0] |= HPTE_V_ABSENT; kvmppc_invalidate_hpte(kvm, hptep, index); /* don't lose previous R and C bits */ r |= hptep[1] & (HPTE_R_R | HPTE_R_C); } else { kvmppc_add_revmap_chain(kvm, rev, rmap, index, 0); } hptep[1] = r; eieio(); hptep[0] = hpte[0]; asm volatile("ptesync" : : : "memory"); preempt_enable(); if (page && hpte_is_writable(r)) SetPageDirty(page); out_put: if (page) { /* * We drop pages[0] here, not page because page might * have been set to the head page of a compound, but * we have to drop the reference on the correct tail * page to match the get inside gup() */ put_page(pages[0]); } return ret; out_unlock: hptep[0] &= ~HPTE_V_HVLOCK; preempt_enable(); goto out_put; } static void kvmppc_rmap_reset(struct kvm *kvm) { struct kvm_memslots *slots; struct kvm_memory_slot *memslot; int srcu_idx; srcu_idx = srcu_read_lock(&kvm->srcu); slots = kvm->memslots; kvm_for_each_memslot(memslot, slots) { /* * This assumes it is acceptable to lose reference and * change bits across a reset. */ memset(memslot->arch.rmap, 0, memslot->npages * sizeof(*memslot->arch.rmap)); } srcu_read_unlock(&kvm->srcu, srcu_idx); } static int kvm_handle_hva_range(struct kvm *kvm, unsigned long start, unsigned long end, int (*handler)(struct kvm *kvm, unsigned long *rmapp, unsigned long gfn)) { int ret; int retval = 0; struct kvm_memslots *slots; struct kvm_memory_slot *memslot; slots = kvm_memslots(kvm); kvm_for_each_memslot(memslot, slots) { unsigned long hva_start, hva_end; gfn_t gfn, gfn_end; hva_start = max(start, memslot->userspace_addr); hva_end = min(end, memslot->userspace_addr + (memslot->npages << PAGE_SHIFT)); if (hva_start >= hva_end) continue; /* * {gfn(page) | page intersects with [hva_start, hva_end)} = * {gfn, gfn+1, ..., gfn_end-1}. */ gfn = hva_to_gfn_memslot(hva_start, memslot); gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot); for (; gfn < gfn_end; ++gfn) { gfn_t gfn_offset = gfn - memslot->base_gfn; ret = handler(kvm, &memslot->arch.rmap[gfn_offset], gfn); retval |= ret; } } return retval; } static int kvm_handle_hva(struct kvm *kvm, unsigned long hva, int (*handler)(struct kvm *kvm, unsigned long *rmapp, unsigned long gfn)) { return kvm_handle_hva_range(kvm, hva, hva + 1, handler); } static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp, unsigned long gfn) { struct revmap_entry *rev = kvm->arch.revmap; unsigned long h, i, j; unsigned long *hptep; unsigned long ptel, psize, rcbits; for (;;) { lock_rmap(rmapp); if (!(*rmapp & KVMPPC_RMAP_PRESENT)) { unlock_rmap(rmapp); break; } /* * To avoid an ABBA deadlock with the HPTE lock bit, * we can't spin on the HPTE lock while holding the * rmap chain lock. */ i = *rmapp & KVMPPC_RMAP_INDEX; hptep = (unsigned long *) (kvm->arch.hpt_virt + (i << 4)); if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) { /* unlock rmap before spinning on the HPTE lock */ unlock_rmap(rmapp); while (hptep[0] & HPTE_V_HVLOCK) cpu_relax(); continue; } j = rev[i].forw; if (j == i) { /* chain is now empty */ *rmapp &= ~(KVMPPC_RMAP_PRESENT | KVMPPC_RMAP_INDEX); } else { /* remove i from chain */ h = rev[i].back; rev[h].forw = j; rev[j].back = h; rev[i].forw = rev[i].back = i; *rmapp = (*rmapp & ~KVMPPC_RMAP_INDEX) | j; } /* Now check and modify the HPTE */ ptel = rev[i].guest_rpte; psize = hpte_page_size(hptep[0], ptel); if ((hptep[0] & HPTE_V_VALID) && hpte_rpn(ptel, psize) == gfn) { if (kvm->arch.using_mmu_notifiers) hptep[0] |= HPTE_V_ABSENT; kvmppc_invalidate_hpte(kvm, hptep, i); /* Harvest R and C */ rcbits = hptep[1] & (HPTE_R_R | HPTE_R_C); *rmapp |= rcbits << KVMPPC_RMAP_RC_SHIFT; if (rcbits & ~rev[i].guest_rpte) { rev[i].guest_rpte = ptel | rcbits; note_hpte_modification(kvm, &rev[i]); } } unlock_rmap(rmapp); hptep[0] &= ~HPTE_V_HVLOCK; } return 0; } int kvm_unmap_hva(struct kvm *kvm, unsigned long hva) { if (kvm->arch.using_mmu_notifiers) kvm_handle_hva(kvm, hva, kvm_unmap_rmapp); return 0; } int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end) { if (kvm->arch.using_mmu_notifiers) kvm_handle_hva_range(kvm, start, end, kvm_unmap_rmapp); return 0; } void kvmppc_core_flush_memslot(struct kvm *kvm, struct kvm_memory_slot *memslot) { unsigned long *rmapp; unsigned long gfn; unsigned long n; rmapp = memslot->arch.rmap; gfn = memslot->base_gfn; for (n = memslot->npages; n; --n) { /* * Testing the present bit without locking is OK because * the memslot has been marked invalid already, and hence * no new HPTEs referencing this page can be created, * thus the present bit can't go from 0 to 1. */ if (*rmapp & KVMPPC_RMAP_PRESENT) kvm_unmap_rmapp(kvm, rmapp, gfn); ++rmapp; ++gfn; } } static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, unsigned long gfn) { struct revmap_entry *rev = kvm->arch.revmap; unsigned long head, i, j; unsigned long *hptep; int ret = 0; retry: lock_rmap(rmapp); if (*rmapp & KVMPPC_RMAP_REFERENCED) { *rmapp &= ~KVMPPC_RMAP_REFERENCED; ret = 1; } if (!(*rmapp & KVMPPC_RMAP_PRESENT)) { unlock_rmap(rmapp); return ret; } i = head = *rmapp & KVMPPC_RMAP_INDEX; do { hptep = (unsigned long *) (kvm->arch.hpt_virt + (i << 4)); j = rev[i].forw; /* If this HPTE isn't referenced, ignore it */ if (!(hptep[1] & HPTE_R_R)) continue; if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) { /* unlock rmap before spinning on the HPTE lock */ unlock_rmap(rmapp); while (hptep[0] & HPTE_V_HVLOCK) cpu_relax(); goto retry; } /* Now check and modify the HPTE */ if ((hptep[0] & HPTE_V_VALID) && (hptep[1] & HPTE_R_R)) { kvmppc_clear_ref_hpte(kvm, hptep, i); if (!(rev[i].guest_rpte & HPTE_R_R)) { rev[i].guest_rpte |= HPTE_R_R; note_hpte_modification(kvm, &rev[i]); } ret = 1; } hptep[0] &= ~HPTE_V_HVLOCK; } while ((i = j) != head); unlock_rmap(rmapp); return ret; } int kvm_age_hva(struct kvm *kvm, unsigned long hva) { if (!kvm->arch.using_mmu_notifiers) return 0; return kvm_handle_hva(kvm, hva, kvm_age_rmapp); } static int kvm_test_age_rmapp(struct kvm *kvm, unsigned long *rmapp, unsigned long gfn) { struct revmap_entry *rev = kvm->arch.revmap; unsigned long head, i, j; unsigned long *hp; int ret = 1; if (*rmapp & KVMPPC_RMAP_REFERENCED) return 1; lock_rmap(rmapp); if (*rmapp & KVMPPC_RMAP_REFERENCED) goto out; if (*rmapp & KVMPPC_RMAP_PRESENT) { i = head = *rmapp & KVMPPC_RMAP_INDEX; do { hp = (unsigned long *)(kvm->arch.hpt_virt + (i << 4)); j = rev[i].forw; if (hp[1] & HPTE_R_R) goto out; } while ((i = j) != head); } ret = 0; out: unlock_rmap(rmapp); return ret; } int kvm_test_age_hva(struct kvm *kvm, unsigned long hva) { if (!kvm->arch.using_mmu_notifiers) return 0; return kvm_handle_hva(kvm, hva, kvm_test_age_rmapp); } void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) { if (!kvm->arch.using_mmu_notifiers) return; kvm_handle_hva(kvm, hva, kvm_unmap_rmapp); } static int kvm_test_clear_dirty(struct kvm *kvm, unsigned long *rmapp) { struct revmap_entry *rev = kvm->arch.revmap; unsigned long head, i, j; unsigned long *hptep; int ret = 0; retry: lock_rmap(rmapp); if (*rmapp & KVMPPC_RMAP_CHANGED) { *rmapp &= ~KVMPPC_RMAP_CHANGED; ret = 1; } if (!(*rmapp & KVMPPC_RMAP_PRESENT)) { unlock_rmap(rmapp); return ret; } i = head = *rmapp & KVMPPC_RMAP_INDEX; do { hptep = (unsigned long *) (kvm->arch.hpt_virt + (i << 4)); j = rev[i].forw; if (!(hptep[1] & HPTE_R_C)) continue; if (!try_lock_hpte(hptep, HPTE_V_HVLOCK)) { /* unlock rmap before spinning on the HPTE lock */ unlock_rmap(rmapp); while (hptep[0] & HPTE_V_HVLOCK) cpu_relax(); goto retry; } /* Now check and modify the HPTE */ if ((hptep[0] & HPTE_V_VALID) && (hptep[1] & HPTE_R_C)) { /* need to make it temporarily absent to clear C */ hptep[0] |= HPTE_V_ABSENT; kvmppc_invalidate_hpte(kvm, hptep, i); hptep[1] &= ~HPTE_R_C; eieio(); hptep[0] = (hptep[0] & ~HPTE_V_ABSENT) | HPTE_V_VALID; if (!(rev[i].guest_rpte & HPTE_R_C)) { rev[i].guest_rpte |= HPTE_R_C; note_hpte_modification(kvm, &rev[i]); } ret = 1; } hptep[0] &= ~HPTE_V_HVLOCK; } while ((i = j) != head); unlock_rmap(rmapp); return ret; } static void harvest_vpa_dirty(struct kvmppc_vpa *vpa, struct kvm_memory_slot *memslot, unsigned long *map) { unsigned long gfn; if (!vpa->dirty || !vpa->pinned_addr) return; gfn = vpa->gpa >> PAGE_SHIFT; if (gfn < memslot->base_gfn || gfn >= memslot->base_gfn + memslot->npages) return; vpa->dirty = false; if (map) __set_bit_le(gfn - memslot->base_gfn, map); } long kvmppc_hv_get_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot, unsigned long *map) { unsigned long i; unsigned long *rmapp; struct kvm_vcpu *vcpu; preempt_disable(); rmapp = memslot->arch.rmap; for (i = 0; i < memslot->npages; ++i) { if (kvm_test_clear_dirty(kvm, rmapp) && map) __set_bit_le(i, map); ++rmapp; } /* Harvest dirty bits from VPA and DTL updates */ /* Note: we never modify the SLB shadow buffer areas */ kvm_for_each_vcpu(i, vcpu, kvm) { spin_lock(&vcpu->arch.vpa_update_lock); harvest_vpa_dirty(&vcpu->arch.vpa, memslot, map); harvest_vpa_dirty(&vcpu->arch.dtl, memslot, map); spin_unlock(&vcpu->arch.vpa_update_lock); } preempt_enable(); return 0; } void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa, unsigned long *nb_ret) { struct kvm_memory_slot *memslot; unsigned long gfn = gpa >> PAGE_SHIFT; struct page *page, *pages[1]; int npages; unsigned long hva, offset; unsigned long pa; unsigned long *physp; int srcu_idx; srcu_idx = srcu_read_lock(&kvm->srcu); memslot = gfn_to_memslot(kvm, gfn); if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) goto err; if (!kvm->arch.using_mmu_notifiers) { physp = memslot->arch.slot_phys; if (!physp) goto err; physp += gfn - memslot->base_gfn; pa = *physp; if (!pa) { if (kvmppc_get_guest_page(kvm, gfn, memslot, PAGE_SIZE) < 0) goto err; pa = *physp; } page = pfn_to_page(pa >> PAGE_SHIFT); get_page(page); } else { hva = gfn_to_hva_memslot(memslot, gfn); npages = get_user_pages_fast(hva, 1, 1, pages); if (npages < 1) goto err; page = pages[0]; } srcu_read_unlock(&kvm->srcu, srcu_idx); offset = gpa & (PAGE_SIZE - 1); if (nb_ret) *nb_ret = PAGE_SIZE - offset; return page_address(page) + offset; err: srcu_read_unlock(&kvm->srcu, srcu_idx); return NULL; } void kvmppc_unpin_guest_page(struct kvm *kvm, void *va, unsigned long gpa, bool dirty) { struct page *page = virt_to_page(va); struct kvm_memory_slot *memslot; unsigned long gfn; unsigned long *rmap; int srcu_idx; put_page(page); if (!dirty || !kvm->arch.using_mmu_notifiers) return; /* We need to mark this page dirty in the rmap chain */ gfn = gpa >> PAGE_SHIFT; srcu_idx = srcu_read_lock(&kvm->srcu); memslot = gfn_to_memslot(kvm, gfn); if (memslot) { rmap = &memslot->arch.rmap[gfn - memslot->base_gfn]; lock_rmap(rmap); *rmap |= KVMPPC_RMAP_CHANGED; unlock_rmap(rmap); } srcu_read_unlock(&kvm->srcu, srcu_idx); } /* * Functions for reading and writing the hash table via reads and * writes on a file descriptor. * * Reads return the guest view of the hash table, which has to be * pieced together from the real hash table and the guest_rpte * values in the revmap array. * * On writes, each HPTE written is considered in turn, and if it * is valid, it is written to the HPT as if an H_ENTER with the * exact flag set was done. When the invalid count is non-zero * in the header written to the stream, the kernel will make * sure that that many HPTEs are invalid, and invalidate them * if not. */ struct kvm_htab_ctx { unsigned long index; unsigned long flags; struct kvm *kvm; int first_pass; }; #define HPTE_SIZE (2 * sizeof(unsigned long)) /* * Returns 1 if this HPT entry has been modified or has pending * R/C bit changes. */ static int hpte_dirty(struct revmap_entry *revp, unsigned long *hptp) { unsigned long rcbits_unset; if (revp->guest_rpte & HPTE_GR_MODIFIED) return 1; /* Also need to consider changes in reference and changed bits */ rcbits_unset = ~revp->guest_rpte & (HPTE_R_R | HPTE_R_C); if ((hptp[0] & HPTE_V_VALID) && (hptp[1] & rcbits_unset)) return 1; return 0; } static long record_hpte(unsigned long flags, unsigned long *hptp, unsigned long *hpte, struct revmap_entry *revp, int want_valid, int first_pass) { unsigned long v, r; unsigned long rcbits_unset; int ok = 1; int valid, dirty; /* Unmodified entries are uninteresting except on the first pass */ dirty = hpte_dirty(revp, hptp); if (!first_pass && !dirty) return 0; valid = 0; if (hptp[0] & (HPTE_V_VALID | HPTE_V_ABSENT)) { valid = 1; if ((flags & KVM_GET_HTAB_BOLTED_ONLY) && !(hptp[0] & HPTE_V_BOLTED)) valid = 0; } if (valid != want_valid) return 0; v = r = 0; if (valid || dirty) { /* lock the HPTE so it's stable and read it */ preempt_disable(); while (!try_lock_hpte(hptp, HPTE_V_HVLOCK)) cpu_relax(); v = hptp[0]; /* re-evaluate valid and dirty from synchronized HPTE value */ valid = !!(v & HPTE_V_VALID); dirty = !!(revp->guest_rpte & HPTE_GR_MODIFIED); /* Harvest R and C into guest view if necessary */ rcbits_unset = ~revp->guest_rpte & (HPTE_R_R | HPTE_R_C); if (valid && (rcbits_unset & hptp[1])) { revp->guest_rpte |= (hptp[1] & (HPTE_R_R | HPTE_R_C)) | HPTE_GR_MODIFIED; dirty = 1; } if (v & HPTE_V_ABSENT) { v &= ~HPTE_V_ABSENT; v |= HPTE_V_VALID; valid = 1; } if ((flags & KVM_GET_HTAB_BOLTED_ONLY) && !(v & HPTE_V_BOLTED)) valid = 0; r = revp->guest_rpte; /* only clear modified if this is the right sort of entry */ if (valid == want_valid && dirty) { r &= ~HPTE_GR_MODIFIED; revp->guest_rpte = r; } asm volatile(PPC_RELEASE_BARRIER "" : : : "memory"); hptp[0] &= ~HPTE_V_HVLOCK; preempt_enable(); if (!(valid == want_valid && (first_pass || dirty))) ok = 0; } hpte[0] = v; hpte[1] = r; return ok; } static ssize_t kvm_htab_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) { struct kvm_htab_ctx *ctx = file->private_data; struct kvm *kvm = ctx->kvm; struct kvm_get_htab_header hdr; unsigned long *hptp; struct revmap_entry *revp; unsigned long i, nb, nw; unsigned long __user *lbuf; struct kvm_get_htab_header __user *hptr; unsigned long flags; int first_pass; unsigned long hpte[2]; if (!access_ok(VERIFY_WRITE, buf, count)) return -EFAULT; first_pass = ctx->first_pass; flags = ctx->flags; i = ctx->index; hptp = (unsigned long *)(kvm->arch.hpt_virt + (i * HPTE_SIZE)); revp = kvm->arch.revmap + i; lbuf = (unsigned long __user *)buf; nb = 0; while (nb + sizeof(hdr) + HPTE_SIZE < count) { /* Initialize header */ hptr = (struct kvm_get_htab_header __user *)buf; hdr.n_valid = 0; hdr.n_invalid = 0; nw = nb; nb += sizeof(hdr); lbuf = (unsigned long __user *)(buf + sizeof(hdr)); /* Skip uninteresting entries, i.e. clean on not-first pass */ if (!first_pass) { while (i < kvm->arch.hpt_npte && !hpte_dirty(revp, hptp)) { ++i; hptp += 2; ++revp; } } hdr.index = i; /* Grab a series of valid entries */ while (i < kvm->arch.hpt_npte && hdr.n_valid < 0xffff && nb + HPTE_SIZE < count && record_hpte(flags, hptp, hpte, revp, 1, first_pass)) { /* valid entry, write it out */ ++hdr.n_valid; if (__put_user(hpte[0], lbuf) || __put_user(hpte[1], lbuf + 1)) return -EFAULT; nb += HPTE_SIZE; lbuf += 2; ++i; hptp += 2; ++revp; } /* Now skip invalid entries while we can */ while (i < kvm->arch.hpt_npte && hdr.n_invalid < 0xffff && record_hpte(flags, hptp, hpte, revp, 0, first_pass)) { /* found an invalid entry */ ++hdr.n_invalid; ++i; hptp += 2; ++revp; } if (hdr.n_valid || hdr.n_invalid) { /* write back the header */ if (__copy_to_user(hptr, &hdr, sizeof(hdr))) return -EFAULT; nw = nb; buf = (char __user *)lbuf; } else { nb = nw; } /* Check if we've wrapped around the hash table */ if (i >= kvm->arch.hpt_npte) { i = 0; ctx->first_pass = 0; break; } } ctx->index = i; return nb; } static ssize_t kvm_htab_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { struct kvm_htab_ctx *ctx = file->private_data; struct kvm *kvm = ctx->kvm; struct kvm_get_htab_header hdr; unsigned long i, j; unsigned long v, r; unsigned long __user *lbuf; unsigned long *hptp; unsigned long tmp[2]; ssize_t nb; long int err, ret; int rma_setup; if (!access_ok(VERIFY_READ, buf, count)) return -EFAULT; /* lock out vcpus from running while we're doing this */ mutex_lock(&kvm->lock); rma_setup = kvm->arch.rma_setup_done; if (rma_setup) { kvm->arch.rma_setup_done = 0; /* temporarily */ /* order rma_setup_done vs. vcpus_running */ smp_mb(); if (atomic_read(&kvm->arch.vcpus_running)) { kvm->arch.rma_setup_done = 1; mutex_unlock(&kvm->lock); return -EBUSY; } } err = 0; for (nb = 0; nb + sizeof(hdr) <= count; ) { err = -EFAULT; if (__copy_from_user(&hdr, buf, sizeof(hdr))) break; err = 0; if (nb + hdr.n_valid * HPTE_SIZE > count) break; nb += sizeof(hdr); buf += sizeof(hdr); err = -EINVAL; i = hdr.index; if (i >= kvm->arch.hpt_npte || i + hdr.n_valid + hdr.n_invalid > kvm->arch.hpt_npte) break; hptp = (unsigned long *)(kvm->arch.hpt_virt + (i * HPTE_SIZE)); lbuf = (unsigned long __user *)buf; for (j = 0; j < hdr.n_valid; ++j) { err = -EFAULT; if (__get_user(v, lbuf) || __get_user(r, lbuf + 1)) goto out; err = -EINVAL; if (!(v & HPTE_V_VALID)) goto out; lbuf += 2; nb += HPTE_SIZE; if (hptp[0] & (HPTE_V_VALID | HPTE_V_ABSENT)) kvmppc_do_h_remove(kvm, 0, i, 0, tmp); err = -EIO; ret = kvmppc_virtmode_do_h_enter(kvm, H_EXACT, i, v, r, tmp); if (ret != H_SUCCESS) { pr_err("kvm_htab_write ret %ld i=%ld v=%lx " "r=%lx\n", ret, i, v, r); goto out; } if (!rma_setup && is_vrma_hpte(v)) { unsigned long psize = hpte_page_size(v, r); unsigned long senc = slb_pgsize_encoding(psize); unsigned long lpcr; kvm->arch.vrma_slb_v = senc | SLB_VSID_B_1T | (VRMA_VSID << SLB_VSID_SHIFT_1T); lpcr = kvm->arch.lpcr & ~LPCR_VRMASD; lpcr |= senc << (LPCR_VRMASD_SH - 4); kvm->arch.lpcr = lpcr; rma_setup = 1; } ++i; hptp += 2; } for (j = 0; j < hdr.n_invalid; ++j) { if (hptp[0] & (HPTE_V_VALID | HPTE_V_ABSENT)) kvmppc_do_h_remove(kvm, 0, i, 0, tmp); ++i; hptp += 2; } err = 0; } out: /* Order HPTE updates vs. rma_setup_done */ smp_wmb(); kvm->arch.rma_setup_done = rma_setup; mutex_unlock(&kvm->lock); if (err) return err; return nb; } static int kvm_htab_release(struct inode *inode, struct file *filp) { struct kvm_htab_ctx *ctx = filp->private_data; filp->private_data = NULL; if (!(ctx->flags & KVM_GET_HTAB_WRITE)) atomic_dec(&ctx->kvm->arch.hpte_mod_interest); kvm_put_kvm(ctx->kvm); kfree(ctx); return 0; } static const struct file_operations kvm_htab_fops = { .read = kvm_htab_read, .write = kvm_htab_write, .llseek = default_llseek, .release = kvm_htab_release, }; int kvm_vm_ioctl_get_htab_fd(struct kvm *kvm, struct kvm_get_htab_fd *ghf) { int ret; struct kvm_htab_ctx *ctx; int rwflag; /* reject flags we don't recognize */ if (ghf->flags & ~(KVM_GET_HTAB_BOLTED_ONLY | KVM_GET_HTAB_WRITE)) return -EINVAL; ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); if (!ctx) return -ENOMEM; kvm_get_kvm(kvm); ctx->kvm = kvm; ctx->index = ghf->start_index; ctx->flags = ghf->flags; ctx->first_pass = 1; rwflag = (ghf->flags & KVM_GET_HTAB_WRITE) ? O_WRONLY : O_RDONLY; ret = anon_inode_getfd("kvm-htab", &kvm_htab_fops, ctx, rwflag); if (ret < 0) { kvm_put_kvm(kvm); return ret; } if (rwflag == O_RDONLY) { mutex_lock(&kvm->slots_lock); atomic_inc(&kvm->arch.hpte_mod_interest); /* make sure kvmppc_do_h_enter etc. see the increment */ synchronize_srcu_expedited(&kvm->srcu); mutex_unlock(&kvm->slots_lock); } return ret; } void kvmppc_mmu_book3s_hv_init(struct kvm_vcpu *vcpu) { struct kvmppc_mmu *mmu = &vcpu->arch.mmu; if (cpu_has_feature(CPU_FTR_ARCH_206)) vcpu->arch.slb_nr = 32; /* POWER7 */ else vcpu->arch.slb_nr = 64; mmu->xlate = kvmppc_mmu_book3s_64_hv_xlate; mmu->reset_msr = kvmppc_mmu_book3s_64_hv_reset_msr; vcpu->arch.hflags |= BOOK3S_HFLAG_SLB; }