From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Adalbert=20Laz=C4=83r?= Subject: [RFC PATCH v1 10/34] KVM: x86: page track: allow page tracking for different EPT views Date: Wed, 22 Jul 2020 19:00:57 +0300 Message-ID: <20200722160121.9601-11-alazar@bitdefender.com> References: <20200722160121.9601-1-alazar@bitdefender.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20200722160121.9601-1-alazar@bitdefender.com> Sender: kvm-owner@vger.kernel.org To: kvm@vger.kernel.org Cc: virtualization@lists.linux-foundation.org, Paolo Bonzini , =?UTF-8?q?=C8=98tefan=20=C8=98icleru?= , =?UTF-8?q?Adalbert=20Laz=C4=83r?= List-Id: virtualization@lists.linuxfoundation.org From: Ștefan Șicleru The introspection tool uses this to set distinct access rights on different EPT views. Signed-off-by: Ștefan Șicleru Signed-off-by: Adalbert Lazăr --- arch/x86/include/asm/kvm_host.h | 2 +- arch/x86/include/asm/kvm_page_track.h | 4 +- arch/x86/kvm/kvmi.c | 6 ++- arch/x86/kvm/mmu.h | 9 ++-- arch/x86/kvm/mmu/mmu.c | 60 +++++++++++++++++---------- arch/x86/kvm/mmu/page_track.c | 56 +++++++++++++------------ drivers/gpu/drm/i915/gvt/kvmgt.c | 8 ++-- 7 files changed, 86 insertions(+), 59 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 5e241863153f..2fbb26b54cf1 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -860,7 +860,7 @@ struct kvm_lpage_info { struct kvm_arch_memory_slot { struct kvm_rmap_head *rmap[KVM_NR_PAGE_SIZES]; struct kvm_lpage_info *lpage_info[KVM_NR_PAGE_SIZES - 1]; - unsigned short *gfn_track[KVM_PAGE_TRACK_MAX]; + unsigned short *gfn_track[KVM_MAX_EPT_VIEWS][KVM_PAGE_TRACK_MAX]; }; /* diff --git a/arch/x86/include/asm/kvm_page_track.h b/arch/x86/include/asm/kvm_page_track.h index c10f0f65c77a..96d2ab7da4a7 100644 --- a/arch/x86/include/asm/kvm_page_track.h +++ b/arch/x86/include/asm/kvm_page_track.h @@ -109,10 +109,10 @@ int kvm_page_track_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot, void kvm_slot_page_track_add_page(struct kvm *kvm, struct kvm_memory_slot *slot, gfn_t gfn, - enum kvm_page_track_mode mode); + enum kvm_page_track_mode mode, u16 view); void kvm_slot_page_track_remove_page(struct kvm *kvm, struct kvm_memory_slot *slot, gfn_t gfn, - enum kvm_page_track_mode mode); + enum kvm_page_track_mode mode, u16 view); bool kvm_page_track_is_active(struct kvm_vcpu *vcpu, gfn_t gfn, enum kvm_page_track_mode mode); diff --git a/arch/x86/kvm/kvmi.c b/arch/x86/kvm/kvmi.c index 4e75858c03b4..7b3b64d27d18 100644 --- a/arch/x86/kvm/kvmi.c +++ b/arch/x86/kvm/kvmi.c @@ -1215,11 +1215,13 @@ void kvmi_arch_update_page_tracking(struct kvm *kvm, if (m->access & allow_bit) { if (slot_tracked) { kvm_slot_page_track_remove_page(kvm, slot, - m->gfn, mode); + m->gfn, mode, + 0); clear_bit(slot->id, arch->active[mode]); } } else if (!slot_tracked) { - kvm_slot_page_track_add_page(kvm, slot, m->gfn, mode); + kvm_slot_page_track_add_page(kvm, slot, m->gfn, mode, + 0); set_bit(slot->id, arch->active[mode]); } } diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h index e2c0518af750..2692b14fb605 100644 --- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -221,11 +221,14 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end); void kvm_mmu_gfn_disallow_lpage(struct kvm_memory_slot *slot, gfn_t gfn); void kvm_mmu_gfn_allow_lpage(struct kvm_memory_slot *slot, gfn_t gfn); bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm, - struct kvm_memory_slot *slot, u64 gfn); + struct kvm_memory_slot *slot, u64 gfn, + u16 view); bool kvm_mmu_slot_gfn_read_protect(struct kvm *kvm, - struct kvm_memory_slot *slot, u64 gfn); + struct kvm_memory_slot *slot, u64 gfn, + u16 view); bool kvm_mmu_slot_gfn_exec_protect(struct kvm *kvm, - struct kvm_memory_slot *slot, u64 gfn); + struct kvm_memory_slot *slot, u64 gfn, + u16 view); int kvm_arch_write_log_dirty(struct kvm_vcpu *vcpu, gpa_t l2_gpa); int kvm_mmu_post_init_vm(struct kvm *kvm); diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 70461c7ef58c..cca12982b795 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -1231,9 +1231,9 @@ static void account_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp) /* the non-leaf shadow pages are keeping readonly. */ if (sp->role.level > PG_LEVEL_4K) { kvm_slot_page_track_add_page(kvm, slot, gfn, - KVM_PAGE_TRACK_PREWRITE); + KVM_PAGE_TRACK_PREWRITE, 0); kvm_slot_page_track_add_page(kvm, slot, gfn, - KVM_PAGE_TRACK_WRITE); + KVM_PAGE_TRACK_WRITE, 0); return; } @@ -1263,9 +1263,9 @@ static void unaccount_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp) slot = __gfn_to_memslot(slots, gfn); if (sp->role.level > PG_LEVEL_4K) { kvm_slot_page_track_remove_page(kvm, slot, gfn, - KVM_PAGE_TRACK_PREWRITE); + KVM_PAGE_TRACK_PREWRITE, 0); kvm_slot_page_track_remove_page(kvm, slot, gfn, - KVM_PAGE_TRACK_WRITE); + KVM_PAGE_TRACK_WRITE, 0); return; } @@ -1617,40 +1617,52 @@ static bool spte_exec_protect(u64 *sptep) static bool __rmap_write_protect(struct kvm *kvm, struct kvm_rmap_head *rmap_head, - bool pt_protect) + bool pt_protect, u16 view) { u64 *sptep; struct rmap_iterator iter; bool flush = false; + struct kvm_mmu_page *sp; - for_each_rmap_spte(rmap_head, &iter, sptep) - flush |= spte_write_protect(sptep, pt_protect); + for_each_rmap_spte(rmap_head, &iter, sptep) { + sp = page_header(__pa(sptep)); + if (view == 0 || (view > 0 && sp->view == view)) + flush |= spte_write_protect(sptep, pt_protect); + } return flush; } static bool __rmap_read_protect(struct kvm *kvm, - struct kvm_rmap_head *rmap_head) + struct kvm_rmap_head *rmap_head, u16 view) { struct rmap_iterator iter; + struct kvm_mmu_page *sp; bool flush = false; u64 *sptep; - for_each_rmap_spte(rmap_head, &iter, sptep) - flush |= spte_read_protect(sptep); + for_each_rmap_spte(rmap_head, &iter, sptep) { + sp = page_header(__pa(sptep)); + if (view == 0 || (view > 0 && sp->view == view)) + flush |= spte_read_protect(sptep); + } return flush; } static bool __rmap_exec_protect(struct kvm *kvm, - struct kvm_rmap_head *rmap_head) + struct kvm_rmap_head *rmap_head, u16 view) { struct rmap_iterator iter; + struct kvm_mmu_page *sp; bool flush = false; u64 *sptep; - for_each_rmap_spte(rmap_head, &iter, sptep) - flush |= spte_exec_protect(sptep); + for_each_rmap_spte(rmap_head, &iter, sptep) { + sp = page_header(__pa(sptep)); + if (view == 0 || (view > 0 && sp->view == view)) + flush |= spte_exec_protect(sptep); + } return flush; } @@ -1745,7 +1757,7 @@ static void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, while (mask) { rmap_head = __gfn_to_rmap(slot->base_gfn + gfn_offset + __ffs(mask), PG_LEVEL_4K, slot); - __rmap_write_protect(kvm, rmap_head, false); + __rmap_write_protect(kvm, rmap_head, false, 0); /* clear the first set bit */ mask &= mask - 1; @@ -1816,7 +1828,8 @@ int kvm_arch_write_log_dirty(struct kvm_vcpu *vcpu, gpa_t l2_gpa) } bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm, - struct kvm_memory_slot *slot, u64 gfn) + struct kvm_memory_slot *slot, u64 gfn, + u16 view) { struct kvm_rmap_head *rmap_head; int i; @@ -1824,14 +1837,16 @@ bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm, for (i = PG_LEVEL_4K; i <= KVM_MAX_HUGEPAGE_LEVEL; ++i) { rmap_head = __gfn_to_rmap(gfn, i, slot); - write_protected |= __rmap_write_protect(kvm, rmap_head, true); + write_protected |= __rmap_write_protect(kvm, rmap_head, true, + view); } return write_protected; } bool kvm_mmu_slot_gfn_read_protect(struct kvm *kvm, - struct kvm_memory_slot *slot, u64 gfn) + struct kvm_memory_slot *slot, u64 gfn, + u16 view) { struct kvm_rmap_head *rmap_head; bool read_protected = false; @@ -1839,14 +1854,15 @@ bool kvm_mmu_slot_gfn_read_protect(struct kvm *kvm, for (i = PG_LEVEL_4K; i <= KVM_MAX_HUGEPAGE_LEVEL; ++i) { rmap_head = __gfn_to_rmap(gfn, i, slot); - read_protected |= __rmap_read_protect(kvm, rmap_head); + read_protected |= __rmap_read_protect(kvm, rmap_head, view); } return read_protected; } bool kvm_mmu_slot_gfn_exec_protect(struct kvm *kvm, - struct kvm_memory_slot *slot, u64 gfn) + struct kvm_memory_slot *slot, u64 gfn, + u16 view) { struct kvm_rmap_head *rmap_head; bool exec_protected = false; @@ -1854,7 +1870,7 @@ bool kvm_mmu_slot_gfn_exec_protect(struct kvm *kvm, for (i = PG_LEVEL_4K; i <= KVM_MAX_HUGEPAGE_LEVEL; ++i) { rmap_head = __gfn_to_rmap(gfn, i, slot); - exec_protected |= __rmap_exec_protect(kvm, rmap_head); + exec_protected |= __rmap_exec_protect(kvm, rmap_head, view); } return exec_protected; @@ -1865,7 +1881,7 @@ static bool rmap_write_protect(struct kvm_vcpu *vcpu, u64 gfn) struct kvm_memory_slot *slot; slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn); - return kvm_mmu_slot_gfn_write_protect(vcpu->kvm, slot, gfn); + return kvm_mmu_slot_gfn_write_protect(vcpu->kvm, slot, gfn, 0); } static bool kvm_zap_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head) @@ -6008,7 +6024,7 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end) static bool slot_rmap_write_protect(struct kvm *kvm, struct kvm_rmap_head *rmap_head) { - return __rmap_write_protect(kvm, rmap_head, false); + return __rmap_write_protect(kvm, rmap_head, false, 0); } void kvm_mmu_slot_remove_write_access(struct kvm *kvm, diff --git a/arch/x86/kvm/mmu/page_track.c b/arch/x86/kvm/mmu/page_track.c index b593bcf80be0..bf26b21cfeb8 100644 --- a/arch/x86/kvm/mmu/page_track.c +++ b/arch/x86/kvm/mmu/page_track.c @@ -20,12 +20,13 @@ void kvm_page_track_free_memslot(struct kvm_memory_slot *slot) { - int i; + int i, view; - for (i = 0; i < KVM_PAGE_TRACK_MAX; i++) { - kvfree(slot->arch.gfn_track[i]); - slot->arch.gfn_track[i] = NULL; - } + for (view = 0; view < KVM_MAX_EPT_VIEWS; view++) + for (i = 0; i < KVM_PAGE_TRACK_MAX; i++) { + kvfree(slot->arch.gfn_track[view][i]); + slot->arch.gfn_track[view][i] = NULL; + } } int kvm_page_track_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot, @@ -33,16 +34,17 @@ int kvm_page_track_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot, { struct kvm_page_track_notifier_head *head; struct kvm_page_track_notifier_node *n; - int idx; - int i; + int view, idx, i; - for (i = 0; i < KVM_PAGE_TRACK_MAX; i++) { - slot->arch.gfn_track[i] = - kvcalloc(npages, sizeof(*slot->arch.gfn_track[i]), - GFP_KERNEL_ACCOUNT); - if (!slot->arch.gfn_track[i]) - goto track_free; - } + for (view = 0; view < KVM_MAX_EPT_VIEWS; view++) + for (i = 0; i < KVM_PAGE_TRACK_MAX; i++) { + slot->arch.gfn_track[view][i] = + kvcalloc(npages, + sizeof(*slot->arch.gfn_track[view][i]), + GFP_KERNEL_ACCOUNT); + if (!slot->arch.gfn_track[view][i]) + goto track_free; + } head = &kvm->arch.track_notifier_head; @@ -71,18 +73,19 @@ static inline bool page_track_mode_is_valid(enum kvm_page_track_mode mode) } static void update_gfn_track(struct kvm_memory_slot *slot, gfn_t gfn, - enum kvm_page_track_mode mode, short count) + enum kvm_page_track_mode mode, short count, + u16 view) { int index, val; index = gfn_to_index(gfn, slot->base_gfn, PG_LEVEL_4K); - val = slot->arch.gfn_track[mode][index]; + val = slot->arch.gfn_track[view][mode][index]; if (WARN_ON(val + count < 0 || val + count > USHRT_MAX)) return; - slot->arch.gfn_track[mode][index] += count; + slot->arch.gfn_track[view][mode][index] += count; } /* @@ -99,13 +102,13 @@ static void update_gfn_track(struct kvm_memory_slot *slot, gfn_t gfn, */ void kvm_slot_page_track_add_page(struct kvm *kvm, struct kvm_memory_slot *slot, gfn_t gfn, - enum kvm_page_track_mode mode) + enum kvm_page_track_mode mode, u16 view) { if (WARN_ON(!page_track_mode_is_valid(mode))) return; - update_gfn_track(slot, gfn, mode, 1); + update_gfn_track(slot, gfn, mode, 1, view); /* * new track stops large page mapping for the @@ -114,13 +117,13 @@ void kvm_slot_page_track_add_page(struct kvm *kvm, kvm_mmu_gfn_disallow_lpage(slot, gfn); if (mode == KVM_PAGE_TRACK_PREWRITE || mode == KVM_PAGE_TRACK_WRITE) { - if (kvm_mmu_slot_gfn_write_protect(kvm, slot, gfn)) + if (kvm_mmu_slot_gfn_write_protect(kvm, slot, gfn, view)) kvm_flush_remote_tlbs(kvm); } else if (mode == KVM_PAGE_TRACK_PREREAD) { - if (kvm_mmu_slot_gfn_read_protect(kvm, slot, gfn)) + if (kvm_mmu_slot_gfn_read_protect(kvm, slot, gfn, view)) kvm_flush_remote_tlbs(kvm); } else if (mode == KVM_PAGE_TRACK_PREEXEC) { - if (kvm_mmu_slot_gfn_exec_protect(kvm, slot, gfn)) + if (kvm_mmu_slot_gfn_exec_protect(kvm, slot, gfn, view)) kvm_flush_remote_tlbs(kvm); } } @@ -141,12 +144,12 @@ EXPORT_SYMBOL_GPL(kvm_slot_page_track_add_page); */ void kvm_slot_page_track_remove_page(struct kvm *kvm, struct kvm_memory_slot *slot, gfn_t gfn, - enum kvm_page_track_mode mode) + enum kvm_page_track_mode mode, u16 view) { if (WARN_ON(!page_track_mode_is_valid(mode))) return; - update_gfn_track(slot, gfn, mode, -1); + update_gfn_track(slot, gfn, mode, -1, view); /* * allow large page mapping for the tracked page @@ -163,7 +166,7 @@ bool kvm_page_track_is_active(struct kvm_vcpu *vcpu, gfn_t gfn, enum kvm_page_track_mode mode) { struct kvm_memory_slot *slot; - int index; + int index, view; if (WARN_ON(!page_track_mode_is_valid(mode))) return false; @@ -173,7 +176,8 @@ bool kvm_page_track_is_active(struct kvm_vcpu *vcpu, gfn_t gfn, return false; index = gfn_to_index(gfn, slot->base_gfn, PG_LEVEL_4K); - return !!READ_ONCE(slot->arch.gfn_track[mode][index]); + view = kvm_get_ept_view(vcpu); + return !!READ_ONCE(slot->arch.gfn_track[view][mode][index]); } void kvm_page_track_cleanup(struct kvm *kvm) diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c index 4e370b216365..98e2e75c0d22 100644 --- a/drivers/gpu/drm/i915/gvt/kvmgt.c +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c @@ -1706,7 +1706,8 @@ static int kvmgt_page_track_add(unsigned long handle, u64 gfn) if (kvmgt_gfn_is_write_protected(info, gfn)) goto out; - kvm_slot_page_track_add_page(kvm, slot, gfn, KVM_PAGE_TRACK_WRITE); + kvm_slot_page_track_add_page(kvm, slot, gfn, + KVM_PAGE_TRACK_WRITE, 0); kvmgt_protect_table_add(info, gfn); out: @@ -1740,7 +1741,8 @@ static int kvmgt_page_track_remove(unsigned long handle, u64 gfn) if (!kvmgt_gfn_is_write_protected(info, gfn)) goto out; - kvm_slot_page_track_remove_page(kvm, slot, gfn, KVM_PAGE_TRACK_WRITE); + kvm_slot_page_track_remove_page(kvm, slot, gfn, + KVM_PAGE_TRACK_WRITE, 0); kvmgt_protect_table_del(info, gfn); out: @@ -1775,7 +1777,7 @@ static void kvmgt_page_track_flush_slot(struct kvm *kvm, gfn = slot->base_gfn + i; if (kvmgt_gfn_is_write_protected(info, gfn)) { kvm_slot_page_track_remove_page(kvm, slot, gfn, - KVM_PAGE_TRACK_WRITE); + KVM_PAGE_TRACK_WRITE, 0); kvmgt_protect_table_del(info, gfn); } }