From 699023e239658e62da6f42f47d31b54788521ec1 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Mon, 18 May 2015 15:03:39 +0200 Subject: [PATCH] KVM: x86: add SMM to the MMU role, support SMRAM address space MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit This is now very simple to do. The only interesting part is a simple trick to find the right memslot in gfn_to_rmap, retrieving the address space from the spte role word. The same trick is used in the auditing code. The comment on top of union kvm_mmu_page_role has been stale forever, so remove it. Speaking of stale code, remove pad_for_nice_hex_output too: it was splitting the "access" bitfield across two bytes and thus had effectively turned into pad_for_ugly_hex_output. Reviewed-by: Radim Krčmář Signed-off-by: Paolo Bonzini --- Documentation/virtual/kvm/mmu.txt | 6 ++++++ arch/x86/include/asm/kvm_host.h | 26 +++++++++++++++----------- arch/x86/kvm/mmu.c | 15 ++++++++++++--- arch/x86/kvm/mmu_audit.c | 10 +++++++--- arch/x86/kvm/x86.c | 2 ++ 5 files changed, 42 insertions(+), 17 deletions(-) diff --git a/Documentation/virtual/kvm/mmu.txt b/Documentation/virtual/kvm/mmu.txt index c59bd9bc41ef..3a4d681c3e98 100644 --- a/Documentation/virtual/kvm/mmu.txt +++ b/Documentation/virtual/kvm/mmu.txt @@ -173,6 +173,12 @@ Shadow pages contain the following information: Contains the value of cr4.smap && !cr0.wp for which the page is valid (pages for which this is true are different from other pages; see the treatment of cr0.wp=0 below). + role.smm: + Is 1 if the page is valid in system management mode. This field + determines which of the kvm_memslots array was used to build this + shadow page; it is also used to go back from a struct kvm_mmu_page + to a memslot, through the kvm_memslots_for_spte_role macro and + __gfn_to_memslot. gfn: Either the guest page table containing the translations shadowed by this page, or the base page frame for linear translations. See role.direct. diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 5a5e13af6e03..47006683f2fe 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -184,23 +184,12 @@ struct kvm_mmu_memory_cache { void *objects[KVM_NR_MEM_OBJS]; }; -/* - * kvm_mmu_page_role, below, is defined as: - * - * bits 0:3 - total guest paging levels (2-4, or zero for real mode) - * bits 4:7 - page table level for this shadow (1-4) - * bits 8:9 - page table quadrant for 2-level guests - * bit 16 - direct mapping of virtual to physical mapping at gfn - * used for real mode and two-dimensional paging - * bits 17:19 - common access permissions for all ptes in this shadow page - */ union kvm_mmu_page_role { unsigned word; struct { unsigned level:4; unsigned cr4_pae:1; unsigned quadrant:2; - unsigned pad_for_nice_hex_output:6; unsigned direct:1; unsigned access:3; unsigned invalid:1; @@ -208,6 +197,15 @@ union kvm_mmu_page_role { unsigned cr0_wp:1; unsigned smep_andnot_wp:1; unsigned smap_andnot_wp:1; + unsigned :8; + + /* + * This is left at the top of the word so that + * kvm_memslots_for_spte_role can extract it with a + * simple shift. While there is room, give it a whole + * byte so it is also faster to load it from memory. + */ + unsigned smm:8; }; }; @@ -1120,6 +1118,12 @@ enum { #define HF_SMM_MASK (1 << 6) #define HF_SMM_INSIDE_NMI_MASK (1 << 7) +#define __KVM_VCPU_MULTIPLE_ADDRESS_SPACE +#define KVM_ADDRESS_SPACE_NUM 2 + +#define kvm_arch_vcpu_memslots_id(vcpu) ((vcpu)->arch.hflags & HF_SMM_MASK ? 1 : 0) +#define kvm_memslots_for_spte_role(kvm, role) __kvm_memslots(kvm, (role).smm) + /* * Hardware virtualization extension instructions may fault if a * reboot turns off virtualization while processes are running. diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 7619e9e1745c..c88f0e443669 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -806,13 +806,15 @@ static struct kvm_lpage_info *lpage_info_slot(gfn_t gfn, static void account_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp) { + struct kvm_memslots *slots; struct kvm_memory_slot *slot; struct kvm_lpage_info *linfo; gfn_t gfn; int i; gfn = sp->gfn; - slot = gfn_to_memslot(kvm, gfn); + slots = kvm_memslots_for_spte_role(kvm, sp->role); + slot = __gfn_to_memslot(slots, gfn); for (i = PT_DIRECTORY_LEVEL; i <= PT_MAX_HUGEPAGE_LEVEL; ++i) { linfo = lpage_info_slot(gfn, slot, i); linfo->write_count += 1; @@ -822,13 +824,15 @@ static void account_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp) static void unaccount_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp) { + struct kvm_memslots *slots; struct kvm_memory_slot *slot; struct kvm_lpage_info *linfo; gfn_t gfn; int i; gfn = sp->gfn; - slot = gfn_to_memslot(kvm, gfn); + slots = kvm_memslots_for_spte_role(kvm, sp->role); + slot = __gfn_to_memslot(slots, gfn); for (i = PT_DIRECTORY_LEVEL; i <= PT_MAX_HUGEPAGE_LEVEL; ++i) { linfo = lpage_info_slot(gfn, slot, i); linfo->write_count -= 1; @@ -1045,9 +1049,11 @@ static unsigned long *__gfn_to_rmap(gfn_t gfn, int level, */ static unsigned long *gfn_to_rmap(struct kvm *kvm, gfn_t gfn, struct kvm_mmu_page *sp) { + struct kvm_memslots *slots; struct kvm_memory_slot *slot; - slot = gfn_to_memslot(kvm, gfn); + slots = kvm_memslots_for_spte_role(kvm, sp->role); + slot = __gfn_to_memslot(slots, gfn); return __gfn_to_rmap(gfn, sp->role.level, slot); } @@ -3924,6 +3930,7 @@ static void init_kvm_tdp_mmu(struct kvm_vcpu *vcpu) struct kvm_mmu *context = &vcpu->arch.mmu; context->base_role.word = 0; + context->base_role.smm = is_smm(vcpu); context->page_fault = tdp_page_fault; context->sync_page = nonpaging_sync_page; context->invlpg = nonpaging_invlpg; @@ -3985,6 +3992,7 @@ void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu) = smep && !is_write_protection(vcpu); context->base_role.smap_andnot_wp = smap && !is_write_protection(vcpu); + context->base_role.smm = is_smm(vcpu); } EXPORT_SYMBOL_GPL(kvm_init_shadow_mmu); @@ -4268,6 +4276,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, mask.nxe = 1; mask.smep_andnot_wp = 1; mask.smap_andnot_wp = 1; + mask.smm = 1; /* * If we don't have indirect shadow pages, it means no page is diff --git a/arch/x86/kvm/mmu_audit.c b/arch/x86/kvm/mmu_audit.c index 78288c15400c..a4f62e6f2db2 100644 --- a/arch/x86/kvm/mmu_audit.c +++ b/arch/x86/kvm/mmu_audit.c @@ -131,12 +131,16 @@ static void inspect_spte_has_rmap(struct kvm *kvm, u64 *sptep) static DEFINE_RATELIMIT_STATE(ratelimit_state, 5 * HZ, 10); unsigned long *rmapp; struct kvm_mmu_page *rev_sp; + struct kvm_memslots *slots; + struct kvm_memory_slot *slot; gfn_t gfn; rev_sp = page_header(__pa(sptep)); gfn = kvm_mmu_page_get_gfn(rev_sp, sptep - rev_sp->spt); - if (!gfn_to_memslot(kvm, gfn)) { + slots = kvm_memslots_for_spte_role(kvm, rev_sp->role); + slot = __gfn_to_memslot(slots, gfn); + if (!slot) { if (!__ratelimit(&ratelimit_state)) return; audit_printk(kvm, "no memslot for gfn %llx\n", gfn); @@ -146,7 +150,7 @@ static void inspect_spte_has_rmap(struct kvm *kvm, u64 *sptep) return; } - rmapp = gfn_to_rmap(kvm, gfn, rev_sp); + rmapp = __gfn_to_rmap(gfn, rev_sp->role.level, slot); if (!*rmapp) { if (!__ratelimit(&ratelimit_state)) return; @@ -197,7 +201,7 @@ static void audit_write_protection(struct kvm *kvm, struct kvm_mmu_page *sp) if (sp->role.direct || sp->unsync || sp->role.invalid) return; - slots = kvm_memslots(kvm); + slots = kvm_memslots_for_spte_role(kvm, sp->role); slot = __gfn_to_memslot(slots, sp->gfn); rmapp = __gfn_to_rmap(sp->gfn, PT_PAGE_TABLE_LEVEL, slot); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index caa0d5f8e6b3..7489871b63df 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5490,6 +5490,8 @@ static void kvm_smm_changed(struct kvm_vcpu *vcpu) kvm_make_request(KVM_REQ_EVENT, vcpu); } } + + kvm_mmu_reset_context(vcpu); } static void kvm_set_hflags(struct kvm_vcpu *vcpu, unsigned emul_flags) -- 2.39.2