diff options
| author | Kees Cook <kees+treewide@kernel.org> | 2026-09-02 15:31:14 -0700 |
|---|---|---|
| committer | Kees Cook <kees@kernel.org> | 2026-09-04 21:37:00 -0700 |
| commit | 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch) | |
| tree | c65086f9bdcd48c6360fb7cb4598bca084da1f32 /arch/x86/kvm/mmu.h | |
| download | linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip | |
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci
This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.
Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.
Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'arch/x86/kvm/mmu.h')
| -rw-r--r-- | arch/x86/kvm/mmu.h | 413 |
1 files changed, 413 insertions, 0 deletions
diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h new file mode 100644 index 000000000..2ae7f9ed4 --- /dev/null +++ b/arch/x86/kvm/mmu.h @@ -0,0 +1,413 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __KVM_X86_MMU_H +#define __KVM_X86_MMU_H + +#include <linux/kvm_host.h> +#include "regs.h" +#include "cpuid.h" + +extern bool __read_mostly tdp_enabled; +#ifdef CONFIG_X86_64 +extern bool __read_mostly tdp_mmu_enabled; +#else +#define tdp_mmu_enabled false +#endif +extern bool __read_mostly enable_mmio_caching; +extern bool __read_mostly eager_page_split; + +#define KVM_MEMSLOT_PAGES_TO_MMU_PAGES_RATIO 50 +#define KVM_MIN_ALLOC_MMU_PAGES 64UL +#define KVM_MMU_HASH_SHIFT 12 +#define KVM_NUM_MMU_PAGES (1 << KVM_MMU_HASH_SHIFT) +#define KVM_MIN_FREE_MMU_PAGES 5 +#define KVM_REFILL_PAGES 25 + +#define PT_WRITABLE_SHIFT 1 +#define PT_USER_SHIFT 2 + +#define PT_PRESENT_MASK (1ULL << 0) +#define PT_WRITABLE_MASK (1ULL << PT_WRITABLE_SHIFT) +#define PT_USER_MASK (1ULL << PT_USER_SHIFT) +#define PT_PWT_MASK (1ULL << 3) +#define PT_PCD_MASK (1ULL << 4) +#define PT_ACCESSED_SHIFT 5 +#define PT_ACCESSED_MASK (1ULL << PT_ACCESSED_SHIFT) +#define PT_DIRTY_SHIFT 6 +#define PT_DIRTY_MASK (1ULL << PT_DIRTY_SHIFT) +#define PT_PAGE_SIZE_SHIFT 7 +#define PT_PAGE_SIZE_MASK (1ULL << PT_PAGE_SIZE_SHIFT) +#define PT_PAT_MASK (1ULL << 7) +#define PT_GLOBAL_MASK (1ULL << 8) +#define PT64_NX_SHIFT 63 +#define PT64_NX_MASK (1ULL << PT64_NX_SHIFT) + +#define PT_PAT_SHIFT 7 +#define PT_DIR_PAT_SHIFT 12 +#define PT_DIR_PAT_MASK (1ULL << PT_DIR_PAT_SHIFT) + +#define PT64_ROOT_5LEVEL 5 +#define PT64_ROOT_4LEVEL 4 +#define PT32_ROOT_LEVEL 2 +#define PT32E_ROOT_LEVEL 3 + +#define ACC_READ_MASK PT_PRESENT_MASK +#define ACC_WRITE_MASK PT_WRITABLE_MASK +#define ACC_USER_MASK PT_USER_MASK /* non EPT */ +#define ACC_USER_EXEC_MASK ACC_USER_MASK /* EPT only */ +#define ACC_EXEC_MASK 8 +#define ACC_ALL (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK | ACC_READ_MASK) + +#define KVM_MMU_CR4_ROLE_BITS (X86_CR4_PSE | X86_CR4_PAE | X86_CR4_LA57 | \ + X86_CR4_SMEP | X86_CR4_SMAP | X86_CR4_PKE) + +#define KVM_MMU_CR0_ROLE_BITS (X86_CR0_PG | X86_CR0_WP) +#define KVM_MMU_EFER_ROLE_BITS (EFER_LME | EFER_NX) + +static __always_inline u64 rsvd_bits(int s, int e) +{ + BUILD_BUG_ON(__builtin_constant_p(e) && __builtin_constant_p(s) && e < s); + + if (__builtin_constant_p(e)) + BUILD_BUG_ON(e > 63); + else + e &= 63; + + if (e < s) + return 0; + + return ((2ULL << (e - s)) - 1) << s; +} + +static inline gfn_t kvm_mmu_max_gfn(void) +{ + /* + * Note that this uses the host MAXPHYADDR, not the guest's. + * EPT/NPT cannot support GPAs that would exceed host.MAXPHYADDR; + * assuming KVM is running on bare metal, guest accesses beyond + * host.MAXPHYADDR will hit a #PF(RSVD) and never cause a vmexit + * (either EPT Violation/Misconfig or #NPF), and so KVM will never + * install a SPTE for such addresses. If KVM is running as a VM + * itself, on the other hand, it might see a MAXPHYADDR that is less + * than hardware's real MAXPHYADDR. Using the host MAXPHYADDR + * disallows such SPTEs entirely and simplifies the TDP MMU. + */ + int max_gpa_bits = likely(tdp_enabled) ? kvm_host.maxphyaddr : 52; + + return (1ULL << (max_gpa_bits - PAGE_SHIFT)) - 1; +} + +static inline bool mmu_has_mbec(struct kvm_mmu *mmu) +{ + return mmu->root_role.cr4_smep; +} + +u8 kvm_mmu_get_max_tdp_level(void); + +void __init kvm_mmu_x86_module_init(void); +int kvm_mmu_vendor_module_init(void); +void kvm_mmu_vendor_module_exit(void); + +void kvm_mmu_destroy(struct kvm_vcpu *vcpu); +int kvm_mmu_create(struct kvm_vcpu *vcpu); +int kvm_mmu_init_vm(struct kvm *kvm); +void kvm_mmu_uninit_vm(struct kvm *kvm); + +void kvm_mmu_init_memslot_memory_attributes(struct kvm *kvm, + struct kvm_memory_slot *slot); + +void kvm_mmu_after_set_cpuid(struct kvm_vcpu *vcpu); +void kvm_mmu_reset_context(struct kvm_vcpu *vcpu); +void kvm_mmu_slot_remove_write_access(struct kvm *kvm, + const struct kvm_memory_slot *memslot, + int start_level); +void kvm_mmu_slot_try_split_huge_pages(struct kvm *kvm, + const struct kvm_memory_slot *memslot, + int target_level); +void kvm_mmu_try_split_huge_pages(struct kvm *kvm, + const struct kvm_memory_slot *memslot, + u64 start, u64 end, + int target_level); +void kvm_mmu_recover_huge_pages(struct kvm *kvm, + const struct kvm_memory_slot *memslot); +void kvm_mmu_slot_leaf_clear_dirty(struct kvm *kvm, + const struct kvm_memory_slot *memslot); +void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm, u64 gen); +void kvm_mmu_change_mmu_pages(struct kvm *kvm, unsigned long kvm_nr_mmu_pages); +void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end); + +void kvm_mmu_set_mmio_spte_mask(u64 mmio_value, u64 mmio_mask, u64 access_mask); +void kvm_mmu_set_mmio_spte_value(struct kvm *kvm, u64 mmio_value); +void kvm_mmu_set_me_spte_mask(u64 me_value, u64 me_mask); +void kvm_mmu_set_ept_masks(bool has_ad_bits); + +void kvm_init_mmu(struct kvm_vcpu *vcpu); +void kvm_init_shadow_npt_mmu(struct kvm_vcpu *vcpu, unsigned long cr4, + u64 efer, gpa_t nested_cr3, u64 misc_ctl); +void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly, + int huge_page_level, bool accessed_dirty, + bool mbec, gpa_t new_eptp); + +int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code, + void *insn, int insn_len); +void kvm_mmu_print_sptes(struct kvm_vcpu *vcpu, gpa_t gpa, const char *msg); +void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva); +void kvm_mmu_invalidate_addr(struct kvm_vcpu *vcpu, struct kvm_pagewalk *w, + u64 addr, unsigned long roots); +void kvm_mmu_invpcid_gva(struct kvm_vcpu *vcpu, gva_t gva, unsigned long pcid); +void kvm_mmu_new_pgd(struct kvm_vcpu *vcpu, gpa_t new_pgd); + +void kvm_configure_mmu(bool enable_tdp, int tdp_forced_root_level, + int tdp_max_root_level, int tdp_huge_page_level); + +bool kvm_can_do_async_pf(struct kvm_vcpu *vcpu); +int kvm_handle_page_fault(struct kvm_vcpu *vcpu, u64 error_code, + u64 fault_address, char *insn, int insn_len); +void __kvm_mmu_refresh_passthrough_bits(struct kvm_vcpu *vcpu, + struct kvm_pagewalk *pw); + +int kvm_mmu_load(struct kvm_vcpu *vcpu); +void kvm_mmu_unload(struct kvm_vcpu *vcpu); +void kvm_mmu_free_obsolete_roots(struct kvm_vcpu *vcpu); +void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu); +void kvm_mmu_sync_prev_roots(struct kvm_vcpu *vcpu); +void kvm_mmu_track_write(struct kvm_vcpu *vcpu, gpa_t gpa, const u8 *new, + int bytes); + +bool __kvm_mmu_unprotect_gfn_and_retry(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, + bool always_retry); + +static inline bool kvm_mmu_unprotect_gfn_and_retry(struct kvm_vcpu *vcpu, + gpa_t cr2_or_gpa) +{ + return __kvm_mmu_unprotect_gfn_and_retry(vcpu, cr2_or_gpa, false); +} + +void kvm_mmu_free_roots(struct kvm *kvm, struct kvm_mmu *mmu, + ulong roots_to_free); +void kvm_mmu_free_guest_mode_roots(struct kvm *kvm, struct kvm_mmu *mmu); +gpa_t kvm_mmu_gva_to_gpa_read(struct kvm_vcpu *vcpu, gva_t gva, + struct x86_exception *exception); +gpa_t kvm_mmu_gva_to_gpa_write(struct kvm_vcpu *vcpu, gva_t gva, + struct x86_exception *exception); +gpa_t kvm_mmu_gva_to_gpa_system(struct kvm_vcpu *vcpu, gva_t gva, + struct x86_exception *exception); + +static inline int kvm_mmu_reload(struct kvm_vcpu *vcpu) +{ + if (kvm_check_request(KVM_REQ_MMU_FREE_OBSOLETE_ROOTS, vcpu)) + kvm_mmu_free_obsolete_roots(vcpu); + + /* + * Checking root.hpa is sufficient even when KVM has mirror root. + * We can have either: + * (1) mirror_root_hpa = INVALID_PAGE, root.hpa = INVALID_PAGE + * (2) mirror_root_hpa = root, root.hpa = INVALID_PAGE + * (3) mirror_root_hpa = root1, root.hpa = root2 + * We don't ever have: + * mirror_root_hpa = INVALID_PAGE, root.hpa = root + */ + if (likely(vcpu->arch.mmu->root.hpa != INVALID_PAGE)) + return 0; + + return kvm_mmu_load(vcpu); +} + +static inline unsigned long kvm_get_pcid(struct kvm_vcpu *vcpu, gpa_t cr3) +{ + BUILD_BUG_ON((X86_CR3_PCID_MASK & PAGE_MASK) != 0); + + return kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE) + ? cr3 & X86_CR3_PCID_MASK + : 0; +} + +static inline unsigned long kvm_get_active_pcid(struct kvm_vcpu *vcpu) +{ + return kvm_get_pcid(vcpu, kvm_read_cr3(vcpu)); +} + +static inline unsigned long kvm_get_active_cr3_lam_bits(struct kvm_vcpu *vcpu) +{ + if (!guest_cpu_cap_has(vcpu, X86_FEATURE_LAM)) + return 0; + + return kvm_read_cr3(vcpu) & (X86_CR3_LAM_U48 | X86_CR3_LAM_U57); +} + +static inline void kvm_mmu_load_pgd(struct kvm_vcpu *vcpu) +{ + u64 root_hpa = vcpu->arch.mmu->root.hpa; + + if (!VALID_PAGE(root_hpa)) + return; + + kvm_x86_call(load_mmu_pgd)(vcpu, root_hpa, + vcpu->arch.mmu->root_role.level); +} + +static inline void kvm_mmu_refresh_passthrough_bits(struct kvm_vcpu *vcpu, + struct kvm_pagewalk *w) +{ + /* + * When EPT is enabled, KVM may passthrough CR0.WP to the guest, i.e. + * @w's snapshot of CR0.WP and thus all related paging metadata may + * be stale. Refresh CR0.WP and the metadata on-demand when checking + * for permission faults. Exempt nested MMUs, i.e. MMUs for shadowing + * nEPT and nNPT, as CR0.WP is ignored in both cases. Note, KVM will + * still refresh gva_walk, so as to honor L2's CR0.WP when translating + * L2 GVAs to GPAs. + */ + if (!tdp_enabled || w == &vcpu->arch.ngpa_walk) + return; + + __kvm_mmu_refresh_passthrough_bits(vcpu, w); +} + +/* + * Check if a given access (described through the I/D, W/R and U/S bits of a + * page fault error code pfec) causes a permission fault with the given PTE + * access rights (in ACC_* format). + * + * Return zero if the access does not fault; return the page fault error code + * if the access faults. + */ +static inline u8 permission_fault(struct kvm_vcpu *vcpu, struct kvm_pagewalk *w, + unsigned pte_access, unsigned pte_pkey, + u64 access) +{ + /* strip nested paging fault error codes */ + unsigned int pfec = access; + unsigned long rflags = kvm_x86_call(get_rflags)(vcpu); + + /* + * For explicit supervisor accesses, SMAP is disabled if EFLAGS.AC = 1. + * For implicit supervisor accesses, SMAP cannot be overridden. + * + * SMAP works on supervisor accesses only, and not_smap can + * be set or not set when user access with neither has any bearing + * on the result. + * + * We put the SMAP checking bit in place of the PFERR_RSVD_MASK bit; + * this bit will always be zero in pfec, but it will be one in index + * if SMAP checks are being disabled. + */ + u64 implicit_access = access & PFERR_IMPLICIT_ACCESS; + bool not_smap = ((rflags & X86_EFLAGS_AC) | implicit_access) == X86_EFLAGS_AC; + int index = (pfec | (not_smap ? PFERR_RSVD_MASK : 0)) >> 1; + struct kvm_page_format *fmt = &w->fmt; + u32 errcode = PFERR_PRESENT_MASK; + bool fault; + + kvm_mmu_refresh_passthrough_bits(vcpu, w); + + fault = (fmt->permissions[index] >> pte_access) & 1; + + WARN_ON_ONCE(pfec & (PFERR_PK_MASK | PFERR_SS_MASK | PFERR_RSVD_MASK)); + if (unlikely(fmt->pkru_mask)) { + u32 pkru_bits, offset; + + /* + * PKRU defines 32 bits, there are 16 domains and 2 + * attribute bits per domain in pkru. pte_pkey is the + * index of the protection domain, so pte_pkey * 2 is + * is the index of the first bit for the domain. + */ + pkru_bits = (vcpu->arch.pkru >> (pte_pkey * 2)) & 3; + + /* clear present bit, replace PFEC.RSVD with ACC_USER_MASK. */ + offset = (pfec & ~1) | ((pte_access & PT_USER_MASK) ? PFERR_RSVD_MASK : 0); + + pkru_bits &= fmt->pkru_mask >> offset; + errcode |= -pkru_bits & PFERR_PK_MASK; + fault |= (pkru_bits != 0); + } + + return -(u32)fault & errcode; +} + +int kvm_mmu_post_init_vm(struct kvm *kvm); +void kvm_mmu_pre_destroy_vm(struct kvm *kvm); + +static inline bool kvm_shadow_root_allocated(struct kvm *kvm) +{ + /* + * Read shadow_root_allocated before related pointers. Hence, threads + * reading shadow_root_allocated in any lock context are guaranteed to + * see the pointers. Pairs with smp_store_release in + * mmu_first_shadow_root_alloc. + */ + return smp_load_acquire(&kvm->arch.shadow_root_allocated); +} + +int kvm_tdp_mmu_map_private_pfn(struct kvm_vcpu *vcpu, gfn_t gfn, kvm_pfn_t pfn); + +static inline bool kvm_memslots_have_rmaps(struct kvm *kvm) +{ + return !tdp_mmu_enabled || kvm_shadow_root_allocated(kvm); +} + +static inline gfn_t gfn_to_index(gfn_t gfn, gfn_t base_gfn, int level) +{ + /* KVM_HPAGE_GFN_SHIFT(PG_LEVEL_4K) must be 0. */ + return (gfn >> KVM_HPAGE_GFN_SHIFT(level)) - + (base_gfn >> KVM_HPAGE_GFN_SHIFT(level)); +} + +static inline unsigned long +__kvm_mmu_slot_lpages(struct kvm_memory_slot *slot, unsigned long npages, + int level) +{ + return gfn_to_index(slot->base_gfn + npages - 1, + slot->base_gfn, level) + 1; +} + +static inline unsigned long +kvm_mmu_slot_lpages(struct kvm_memory_slot *slot, int level) +{ + return __kvm_mmu_slot_lpages(slot, slot->npages, level); +} + +static inline void kvm_update_page_stats(struct kvm *kvm, int level, int count) +{ + atomic64_add(count, &kvm->stat.pages[level - 1]); +} + +static inline bool mmu_is_nested(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.mmu == &vcpu->arch.guest_mmu; +} + +static inline gpa_t kvm_translate_gpa(struct kvm_vcpu *vcpu, + struct kvm_pagewalk *w, + gpa_t gpa, u64 access, + struct x86_exception *exception, + u64 pte_access) +{ + if (!mmu_is_nested(vcpu) || w == &vcpu->arch.ngpa_walk) + return gpa; + return kvm_nested_call(translate_nested_gpa)(vcpu, gpa, access, + exception, pte_access); +} + +static inline bool kvm_has_mirrored_tdp(const struct kvm *kvm) +{ + return kvm->arch.vm_type == KVM_X86_TDX_VM; +} + +static inline gfn_t kvm_gfn_direct_bits(const struct kvm *kvm) +{ + return kvm->arch.gfn_direct_bits; +} + +static inline bool kvm_is_addr_direct(struct kvm *kvm, gpa_t gpa) +{ + gpa_t gpa_direct_bits = gfn_to_gpa(kvm_gfn_direct_bits(kvm)); + + return !gpa_direct_bits || (gpa & gpa_direct_bits); +} + +static inline bool kvm_is_gfn_alias(struct kvm *kvm, gfn_t gfn) +{ + return gfn & kvm_gfn_direct_bits(kvm); +} +#endif |
