From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8DE7DC31E40 for ; Fri, 9 Aug 2019 16:20:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4319620C01 for ; Fri, 9 Aug 2019 16:20:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2437253AbfHIQUS (ORCPT ); Fri, 9 Aug 2019 12:20:18 -0400 Received: from mx01.bbu.dsd.mx.bitdefender.com ([91.199.104.161]:53310 "EHLO mx01.bbu.dsd.mx.bitdefender.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2437140AbfHIQUB (ORCPT ); Fri, 9 Aug 2019 12:20:01 -0400 Received: from smtp.bitdefender.com (smtp02.buh.bitdefender.net [10.17.80.76]) by mx01.bbu.dsd.mx.bitdefender.com (Postfix) with ESMTPS id 7FAAD301ACC2; Fri, 9 Aug 2019 19:01:00 +0300 (EEST) Received: from localhost.localdomain (unknown [89.136.169.210]) by smtp.bitdefender.com (Postfix) with ESMTPSA id 341AA305B7A0; Fri, 9 Aug 2019 19:01:00 +0300 (EEST) From: =?UTF-8?q?Adalbert=20Laz=C4=83r?= To: kvm@vger.kernel.org Cc: linux-mm@kvack.org, virtualization@lists.linux-foundation.org, Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Konrad Rzeszutek Wilk , Tamas K Lengyel , Mathieu Tarral , =?UTF-8?q?Samuel=20Laur=C3=A9n?= , Patrick Colp , Jan Kiszka , Stefan Hajnoczi , Weijiang Yang , Zhang@vger.kernel.org, Yu C , =?UTF-8?q?Mihai=20Don=C8=9Bu?= , =?UTF-8?q?Adalbert=20Laz=C4=83r?= , Sean Christopherson , Joerg Roedel Subject: [RFC PATCH v6 24/92] kvm: x86: wire in the preread/prewrite/preexec page trackers Date: Fri, 9 Aug 2019 18:59:39 +0300 Message-Id: <20190809160047.8319-25-alazar@bitdefender.com> In-Reply-To: <20190809160047.8319-1-alazar@bitdefender.com> References: <20190809160047.8319-1-alazar@bitdefender.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Mihai Donțu These are needed by the introspection subsystem. CC: Sean Christopherson CC: Joerg Roedel Signed-off-by: Mihai Donțu Signed-off-by: Adalbert Lazăr --- arch/x86/include/asm/kvm_emulate.h | 1 + arch/x86/kvm/emulate.c | 10 +++++- arch/x86/kvm/mmu.c | 37 ++++++++++++++------- arch/x86/kvm/x86.c | 52 ++++++++++++++++++++++++------ 4 files changed, 79 insertions(+), 21 deletions(-) diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h index 93c4bf598fb0..97cb592687cb 100644 --- a/arch/x86/include/asm/kvm_emulate.h +++ b/arch/x86/include/asm/kvm_emulate.h @@ -444,6 +444,7 @@ bool x86_page_table_writing_insn(struct x86_emulate_ctxt *ctxt); #define EMULATION_OK 0 #define EMULATION_RESTART 1 #define EMULATION_INTERCEPTED 2 +#define EMULATION_RETRY_INSTR 3 void init_decode_cache(struct x86_emulate_ctxt *ctxt); int x86_emulate_insn(struct x86_emulate_ctxt *ctxt); int emulator_task_switch(struct x86_emulate_ctxt *ctxt, diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index c338984c850d..34431cf31f74 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -5366,7 +5366,12 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len) ctxt->memopp->addr.mem.ea + ctxt->_eip); done: - return (rc != X86EMUL_CONTINUE) ? EMULATION_FAILED : EMULATION_OK; + if (rc == X86EMUL_RETRY_INSTR) + return EMULATION_RETRY_INSTR; + else if (rc == X86EMUL_CONTINUE) + return EMULATION_OK; + else + return EMULATION_FAILED; } bool x86_page_table_writing_insn(struct x86_emulate_ctxt *ctxt) @@ -5736,6 +5741,9 @@ int x86_emulate_insn(struct x86_emulate_ctxt *ctxt) if (rc == X86EMUL_INTERCEPTED) return EMULATION_INTERCEPTED; + if (rc == X86EMUL_RETRY_INSTR) + return EMULATION_RETRY_INSTR; + if (rc == X86EMUL_CONTINUE) writeback_registers(ctxt); diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index a86b165cf6dd..ff053f17b8c2 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1111,9 +1111,13 @@ static void account_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp) slot = __gfn_to_memslot(slots, gfn); /* the non-leaf shadow pages are keeping readonly. */ - if (sp->role.level > PT_PAGE_TABLE_LEVEL) - return kvm_slot_page_track_add_page(kvm, slot, gfn, - KVM_PAGE_TRACK_WRITE); + if (sp->role.level > PT_PAGE_TABLE_LEVEL) { + kvm_slot_page_track_add_page(kvm, slot, gfn, + KVM_PAGE_TRACK_PREWRITE); + kvm_slot_page_track_add_page(kvm, slot, gfn, + KVM_PAGE_TRACK_WRITE); + return; + } kvm_mmu_gfn_disallow_lpage(slot, gfn); } @@ -1128,9 +1132,13 @@ static void unaccount_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp) gfn = sp->gfn; slots = kvm_memslots_for_spte_role(kvm, sp->role); slot = __gfn_to_memslot(slots, gfn); - if (sp->role.level > PT_PAGE_TABLE_LEVEL) - return kvm_slot_page_track_remove_page(kvm, slot, gfn, - KVM_PAGE_TRACK_WRITE); + if (sp->role.level > PT_PAGE_TABLE_LEVEL) { + kvm_slot_page_track_remove_page(kvm, slot, gfn, + KVM_PAGE_TRACK_PREWRITE); + kvm_slot_page_track_remove_page(kvm, slot, gfn, + KVM_PAGE_TRACK_WRITE); + return; + } kvm_mmu_gfn_allow_lpage(slot, gfn); } @@ -2884,7 +2892,8 @@ static bool mmu_need_write_protect(struct kvm_vcpu *vcpu, gfn_t gfn, { struct kvm_mmu_page *sp; - if (kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_WRITE)) + if (kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_PREWRITE) || + kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_WRITE)) return true; for_each_gfn_indirect_valid_sp(vcpu->kvm, sp, gfn) { @@ -4006,15 +4015,21 @@ static bool page_fault_handle_page_track(struct kvm_vcpu *vcpu, if (unlikely(error_code & PFERR_RSVD_MASK)) return false; - if (!(error_code & PFERR_PRESENT_MASK) || - !(error_code & PFERR_WRITE_MASK)) + if (!(error_code & PFERR_PRESENT_MASK)) return false; /* - * guest is writing the page which is write tracked which can + * guest is reading/writing/fetching the page which is + * read/write/execute tracked which can * not be fixed by page fault handler. */ - if (kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_WRITE)) + if (((error_code & PFERR_USER_MASK) + && kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_PREREAD)) + || ((error_code & PFERR_WRITE_MASK) + && (kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_PREWRITE) + || kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_WRITE))) + || ((error_code & PFERR_FETCH_MASK) + && kvm_page_track_is_active(vcpu, gfn, KVM_PAGE_TRACK_PREEXEC))) return true; return false; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index d3d159986243..7aef002be551 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5065,6 +5065,7 @@ static int kvm_read_guest_virt_helper(gva_t addr, void *val, unsigned int bytes, { void *data = val; int r = X86EMUL_CONTINUE; + bool data_ready; while (bytes) { gpa_t gpa = vcpu->arch.walk_mmu->gva_to_gpa(vcpu, addr, access, @@ -5075,6 +5076,13 @@ static int kvm_read_guest_virt_helper(gva_t addr, void *val, unsigned int bytes, if (gpa == UNMAPPED_GVA) return X86EMUL_PROPAGATE_FAULT; + if (!kvm_page_track_preread(vcpu, gpa, addr, data, toread, + &data_ready)) + return X86EMUL_RETRY_INSTR; + if (data_ready) { + WARN_ON(toread > bytes); /* TODO */ + return X86EMUL_CONTINUE; + } ret = kvm_vcpu_read_guest_page(vcpu, gpa >> PAGE_SHIFT, data, offset, toread); if (ret < 0) { @@ -5106,6 +5114,9 @@ static int kvm_fetch_guest_virt(struct x86_emulate_ctxt *ctxt, if (unlikely(gpa == UNMAPPED_GVA)) return X86EMUL_PROPAGATE_FAULT; + if (!kvm_page_track_preexec(vcpu, gpa, addr)) + return X86EMUL_RETRY_INSTR; + offset = addr & (PAGE_SIZE-1); if (WARN_ON(offset + bytes > PAGE_SIZE)) bytes = (unsigned)PAGE_SIZE - offset; @@ -5284,13 +5295,26 @@ static int vcpu_mmio_gva_to_gpa(struct kvm_vcpu *vcpu, unsigned long gva, int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa, gva_t gva, const void *val, int bytes) { - int ret; - - ret = kvm_vcpu_write_guest(vcpu, gpa, val, bytes); - if (ret < 0) - return 0; + if (!kvm_page_track_prewrite(vcpu, gpa, gva, val, bytes)) + return X86EMUL_RETRY_INSTR; + if (kvm_vcpu_write_guest(vcpu, gpa, val, bytes) < 0) + return X86EMUL_UNHANDLEABLE; kvm_page_track_write(vcpu, gpa, gva, val, bytes); - return 1; + return X86EMUL_CONTINUE; +} + +static int emulator_read_phys(struct kvm_vcpu *vcpu, gpa_t gpa, gva_t gva, + void *val, int bytes) +{ + bool data_ready; + + if (!kvm_page_track_preread(vcpu, gpa, gva, val, bytes, &data_ready)) + return X86EMUL_RETRY_INSTR; + if (data_ready) + return X86EMUL_CONTINUE; + if (kvm_vcpu_read_guest(vcpu, gpa, val, bytes) < 0) + return X86EMUL_UNHANDLEABLE; + return X86EMUL_CONTINUE; } struct read_write_emulator_ops { @@ -5320,7 +5344,7 @@ static int read_prepare(struct kvm_vcpu *vcpu, void *val, int bytes) static int read_emulate(struct kvm_vcpu *vcpu, gpa_t gpa, gva_t gva, void *val, int bytes) { - return !kvm_vcpu_read_guest(vcpu, gpa, val, bytes); + return emulator_read_phys(vcpu, gpa, gva, val, bytes); } static int write_emulate(struct kvm_vcpu *vcpu, gpa_t gpa, gva_t gva, @@ -5395,8 +5419,11 @@ static int emulator_read_write_onepage(unsigned long addr, void *val, return X86EMUL_PROPAGATE_FAULT; } - if (!ret && ops->read_write_emulate(vcpu, gpa, addr, val, bytes)) - return X86EMUL_CONTINUE; + if (!ret) { + ret = ops->read_write_emulate(vcpu, gpa, addr, val, bytes); + if (ret == X86EMUL_CONTINUE || ret == X86EMUL_RETRY_INSTR) + return ret; + } /* * Is this MMIO handled locally? @@ -5531,6 +5558,9 @@ static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt, if (is_error_page(page)) goto emul_write; + if (!kvm_page_track_prewrite(vcpu, gpa, addr, new, bytes)) + return X86EMUL_RETRY_INSTR; + kaddr = kmap_atomic(page); kaddr += offset_in_page(gpa); switch (bytes) { @@ -6416,6 +6446,8 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, trace_kvm_emulate_insn_start(vcpu); ++vcpu->stat.insn_emulation; + if (r == EMULATION_RETRY_INSTR) + return EMULATE_DONE; if (r != EMULATION_OK) { if (emulation_type & EMULTYPE_TRAP_UD) return EMULATE_FAIL; @@ -6457,6 +6489,8 @@ int x86_emulate_instruction(struct kvm_vcpu *vcpu, r = x86_emulate_insn(ctxt); + if (r == EMULATION_RETRY_INSTR) + return EMULATE_DONE; if (r == EMULATION_INTERCEPTED) return EMULATE_DONE;