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author | Linus Torvalds <torvalds@linux-foundation.org> | 2024-01-18 00:03:37 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2024-01-18 00:03:37 +0300 |
commit | 09d1c6a80f2cf94c6e70be919203473d4ab8e26c (patch) | |
tree | 144604e6cf9f513c45c4d035548ac1760e7dac11 /arch/x86/kvm/vmx/vmx.c | |
parent | 1b1934dbbdcf9aa2d507932ff488cec47999cf3f (diff) | |
parent | 1c6d984f523f67ecfad1083bb04c55d91977bb15 (diff) | |
download | linux-09d1c6a80f2cf94c6e70be919203473d4ab8e26c.tar.xz |
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
"Generic:
- Use memdup_array_user() to harden against overflow.
- Unconditionally advertise KVM_CAP_DEVICE_CTRL for all
architectures.
- Clean up Kconfigs that all KVM architectures were selecting
- New functionality around "guest_memfd", a new userspace API that
creates an anonymous file and returns a file descriptor that refers
to it. guest_memfd files are bound to their owning virtual machine,
cannot be mapped, read, or written by userspace, and cannot be
resized. guest_memfd files do however support PUNCH_HOLE, which can
be used to switch a memory area between guest_memfd and regular
anonymous memory.
- New ioctl KVM_SET_MEMORY_ATTRIBUTES allowing userspace to specify
per-page attributes for a given page of guest memory; right now the
only attribute is whether the guest expects to access memory via
guest_memfd or not, which in Confidential SVMs backed by SEV-SNP,
TDX or ARM64 pKVM is checked by firmware or hypervisor that
guarantees confidentiality (AMD PSP, Intel TDX module, or EL2 in
the case of pKVM).
x86:
- Support for "software-protected VMs" that can use the new
guest_memfd and page attributes infrastructure. This is mostly
useful for testing, since there is no pKVM-like infrastructure to
provide a meaningfully reduced TCB.
- Fix a relatively benign off-by-one error when splitting huge pages
during CLEAR_DIRTY_LOG.
- Fix a bug where KVM could incorrectly test-and-clear dirty bits in
non-leaf TDP MMU SPTEs if a racing thread replaces a huge SPTE with
a non-huge SPTE.
- Use more generic lockdep assertions in paths that don't actually
care about whether the caller is a reader or a writer.
- let Xen guests opt out of having PV clock reported as "based on a
stable TSC", because some of them don't expect the "TSC stable" bit
(added to the pvclock ABI by KVM, but never set by Xen) to be set.
- Revert a bogus, made-up nested SVM consistency check for
TLB_CONTROL.
- Advertise flush-by-ASID support for nSVM unconditionally, as KVM
always flushes on nested transitions, i.e. always satisfies flush
requests. This allows running bleeding edge versions of VMware
Workstation on top of KVM.
- Sanity check that the CPU supports flush-by-ASID when enabling SEV
support.
- On AMD machines with vNMI, always rely on hardware instead of
intercepting IRET in some cases to detect unmasking of NMIs
- Support for virtualizing Linear Address Masking (LAM)
- Fix a variety of vPMU bugs where KVM fail to stop/reset counters
and other state prior to refreshing the vPMU model.
- Fix a double-overflow PMU bug by tracking emulated counter events
using a dedicated field instead of snapshotting the "previous"
counter. If the hardware PMC count triggers overflow that is
recognized in the same VM-Exit that KVM manually bumps an event
count, KVM would pend PMIs for both the hardware-triggered overflow
and for KVM-triggered overflow.
- Turn off KVM_WERROR by default for all configs so that it's not
inadvertantly enabled by non-KVM developers, which can be
problematic for subsystems that require no regressions for W=1
builds.
- Advertise all of the host-supported CPUID bits that enumerate
IA32_SPEC_CTRL "features".
- Don't force a masterclock update when a vCPU synchronizes to the
current TSC generation, as updating the masterclock can cause
kvmclock's time to "jump" unexpectedly, e.g. when userspace
hotplugs a pre-created vCPU.
- Use RIP-relative address to read kvm_rebooting in the VM-Enter
fault paths, partly as a super minor optimization, but mostly to
make KVM play nice with position independent executable builds.
- Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on
CONFIG_HYPERV as a minor optimization, and to self-document the
code.
- Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV
"emulation" at build time.
ARM64:
- LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB base
granule sizes. Branch shared with the arm64 tree.
- Large Fine-Grained Trap rework, bringing some sanity to the
feature, although there is more to come. This comes with a prefix
branch shared with the arm64 tree.
- Some additional Nested Virtualization groundwork, mostly
introducing the NV2 VNCR support and retargetting the NV support to
that version of the architecture.
- A small set of vgic fixes and associated cleanups.
Loongarch:
- Optimization for memslot hugepage checking
- Cleanup and fix some HW/SW timer issues
- Add LSX/LASX (128bit/256bit SIMD) support
RISC-V:
- KVM_GET_REG_LIST improvement for vector registers
- Generate ISA extension reg_list using macros in get-reg-list
selftest
- Support for reporting steal time along with selftest
s390:
- Bugfixes
Selftests:
- Fix an annoying goof where the NX hugepage test prints out garbage
instead of the magic token needed to run the test.
- Fix build errors when a header is delete/moved due to a missing
flag in the Makefile.
- Detect if KVM bugged/killed a selftest's VM and print out a helpful
message instead of complaining that a random ioctl() failed.
- Annotate the guest printf/assert helpers with __printf(), and fix
the various bugs that were lurking due to lack of said annotation"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (185 commits)
x86/kvm: Do not try to disable kvmclock if it was not enabled
KVM: x86: add missing "depends on KVM"
KVM: fix direction of dependency on MMU notifiers
KVM: introduce CONFIG_KVM_COMMON
KVM: arm64: Add missing memory barriers when switching to pKVM's hyp pgd
KVM: arm64: vgic-its: Avoid potential UAF in LPI translation cache
RISC-V: KVM: selftests: Add get-reg-list test for STA registers
RISC-V: KVM: selftests: Add steal_time test support
RISC-V: KVM: selftests: Add guest_sbi_probe_extension
RISC-V: KVM: selftests: Move sbi_ecall to processor.c
RISC-V: KVM: Implement SBI STA extension
RISC-V: KVM: Add support for SBI STA registers
RISC-V: KVM: Add support for SBI extension registers
RISC-V: KVM: Add SBI STA info to vcpu_arch
RISC-V: KVM: Add steal-update vcpu request
RISC-V: KVM: Add SBI STA extension skeleton
RISC-V: paravirt: Implement steal-time support
RISC-V: Add SBI STA extension definitions
RISC-V: paravirt: Add skeleton for pv-time support
RISC-V: KVM: Fix indentation in kvm_riscv_vcpu_set_reg_csr()
...
Diffstat (limited to 'arch/x86/kvm/vmx/vmx.c')
-rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 86 |
1 files changed, 67 insertions, 19 deletions
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index e0f86f11c345..e262bc2ba4e5 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -66,6 +66,7 @@ #include "vmx.h" #include "x86.h" #include "smm.h" +#include "vmx_onhyperv.h" MODULE_AUTHOR("Qumranet"); MODULE_LICENSE("GPL"); @@ -523,22 +524,14 @@ module_param(enlightened_vmcs, bool, 0444); static int hv_enable_l2_tlb_flush(struct kvm_vcpu *vcpu) { struct hv_enlightened_vmcs *evmcs; - struct hv_partition_assist_pg **p_hv_pa_pg = - &to_kvm_hv(vcpu->kvm)->hv_pa_pg; - /* - * Synthetic VM-Exit is not enabled in current code and so All - * evmcs in singe VM shares same assist page. - */ - if (!*p_hv_pa_pg) - *p_hv_pa_pg = kzalloc(PAGE_SIZE, GFP_KERNEL_ACCOUNT); + hpa_t partition_assist_page = hv_get_partition_assist_page(vcpu); - if (!*p_hv_pa_pg) + if (partition_assist_page == INVALID_PAGE) return -ENOMEM; evmcs = (struct hv_enlightened_vmcs *)to_vmx(vcpu)->loaded_vmcs->vmcs; - evmcs->partition_assist_page = - __pa(*p_hv_pa_pg); + evmcs->partition_assist_page = partition_assist_page; evmcs->hv_vm_id = (unsigned long)vcpu->kvm; evmcs->hv_enlightenments_control.nested_flush_hypercall = 1; @@ -2055,6 +2048,7 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) if (vmx_get_vmx_msr(&vmx->nested.msrs, msr_info->index, &msr_info->data)) return 1; +#ifdef CONFIG_KVM_HYPERV /* * Enlightened VMCS v1 doesn't have certain VMCS fields but * instead of just ignoring the features, different Hyper-V @@ -2065,6 +2059,7 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) if (!msr_info->host_initiated && guest_cpuid_has_evmcs(vcpu)) nested_evmcs_filter_control_msr(vcpu, msr_info->index, &msr_info->data); +#endif break; case MSR_IA32_RTIT_CTL: if (!vmx_pt_mode_is_host_guest()) @@ -3400,7 +3395,8 @@ static void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, update_guest_cr3 = false; vmx_ept_load_pdptrs(vcpu); } else { - guest_cr3 = root_hpa | kvm_get_active_pcid(vcpu); + guest_cr3 = root_hpa | kvm_get_active_pcid(vcpu) | + kvm_get_active_cr3_lam_bits(vcpu); } if (update_guest_cr3) @@ -4833,7 +4829,10 @@ static void __vmx_vcpu_reset(struct kvm_vcpu *vcpu) vmx->nested.posted_intr_nv = -1; vmx->nested.vmxon_ptr = INVALID_GPA; vmx->nested.current_vmptr = INVALID_GPA; + +#ifdef CONFIG_KVM_HYPERV vmx->nested.hv_evmcs_vmptr = EVMPTR_INVALID; +#endif vcpu->arch.microcode_version = 0x100000000ULL; vmx->msr_ia32_feature_control_valid_bits = FEAT_CTL_LOCKED; @@ -5782,7 +5781,7 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu) * would also use advanced VM-exit information for EPT violations to * reconstruct the page fault error code. */ - if (unlikely(allow_smaller_maxphyaddr && kvm_vcpu_is_illegal_gpa(vcpu, gpa))) + if (unlikely(allow_smaller_maxphyaddr && !kvm_vcpu_is_legal_gpa(vcpu, gpa))) return kvm_emulate_instruction(vcpu, 0); return kvm_mmu_page_fault(vcpu, gpa, error_code, NULL, 0); @@ -6757,10 +6756,10 @@ static void vmx_set_apic_access_page_addr(struct kvm_vcpu *vcpu) return; /* - * Grab the memslot so that the hva lookup for the mmu_notifier retry - * is guaranteed to use the same memslot as the pfn lookup, i.e. rely - * on the pfn lookup's validation of the memslot to ensure a valid hva - * is used for the retry check. + * Explicitly grab the memslot using KVM's internal slot ID to ensure + * KVM doesn't unintentionally grab a userspace memslot. It _should_ + * be impossible for userspace to create a memslot for the APIC when + * APICv is enabled, but paranoia won't hurt in this case. */ slot = id_to_memslot(slots, APIC_ACCESS_PAGE_PRIVATE_MEMSLOT); if (!slot || slot->flags & KVM_MEMSLOT_INVALID) @@ -6785,8 +6784,7 @@ static void vmx_set_apic_access_page_addr(struct kvm_vcpu *vcpu) return; read_lock(&vcpu->kvm->mmu_lock); - if (mmu_invalidate_retry_hva(kvm, mmu_seq, - gfn_to_hva_memslot(slot, gfn))) { + if (mmu_invalidate_retry_gfn(kvm, mmu_seq, gfn)) { kvm_make_request(KVM_REQ_APIC_PAGE_RELOAD, vcpu); read_unlock(&vcpu->kvm->mmu_lock); goto out; @@ -7674,6 +7672,9 @@ static void nested_vmx_cr_fixed1_bits_update(struct kvm_vcpu *vcpu) cr4_fixed1_update(X86_CR4_UMIP, ecx, feature_bit(UMIP)); cr4_fixed1_update(X86_CR4_LA57, ecx, feature_bit(LA57)); + entry = kvm_find_cpuid_entry_index(vcpu, 0x7, 1); + cr4_fixed1_update(X86_CR4_LAM_SUP, eax, feature_bit(LAM)); + #undef cr4_fixed1_update } @@ -7760,6 +7761,7 @@ static void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_XSAVES); kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_VMX); + kvm_governed_feature_check_and_set(vcpu, X86_FEATURE_LAM); vmx_setup_uret_msrs(vmx); @@ -8206,6 +8208,50 @@ static void vmx_vm_destroy(struct kvm *kvm) free_pages((unsigned long)kvm_vmx->pid_table, vmx_get_pid_table_order(kvm)); } +/* + * Note, the SDM states that the linear address is masked *after* the modified + * canonicality check, whereas KVM masks (untags) the address and then performs + * a "normal" canonicality check. Functionally, the two methods are identical, + * and when the masking occurs relative to the canonicality check isn't visible + * to software, i.e. KVM's behavior doesn't violate the SDM. + */ +gva_t vmx_get_untagged_addr(struct kvm_vcpu *vcpu, gva_t gva, unsigned int flags) +{ + int lam_bit; + unsigned long cr3_bits; + + if (flags & (X86EMUL_F_FETCH | X86EMUL_F_IMPLICIT | X86EMUL_F_INVLPG)) + return gva; + + if (!is_64_bit_mode(vcpu)) + return gva; + + /* + * Bit 63 determines if the address should be treated as user address + * or a supervisor address. + */ + if (!(gva & BIT_ULL(63))) { + cr3_bits = kvm_get_active_cr3_lam_bits(vcpu); + if (!(cr3_bits & (X86_CR3_LAM_U57 | X86_CR3_LAM_U48))) + return gva; + + /* LAM_U48 is ignored if LAM_U57 is set. */ + lam_bit = cr3_bits & X86_CR3_LAM_U57 ? 56 : 47; + } else { + if (!kvm_is_cr4_bit_set(vcpu, X86_CR4_LAM_SUP)) + return gva; + + lam_bit = kvm_is_cr4_bit_set(vcpu, X86_CR4_LA57) ? 56 : 47; + } + + /* + * Untag the address by sign-extending the lam_bit, but NOT to bit 63. + * Bit 63 is retained from the raw virtual address so that untagging + * doesn't change a user access to a supervisor access, and vice versa. + */ + return (sign_extend64(gva, lam_bit) & ~BIT_ULL(63)) | (gva & BIT_ULL(63)); +} + static struct kvm_x86_ops vmx_x86_ops __initdata = { .name = KBUILD_MODNAME, @@ -8346,6 +8392,8 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = { .complete_emulated_msr = kvm_complete_insn_gp, .vcpu_deliver_sipi_vector = kvm_vcpu_deliver_sipi_vector, + + .get_untagged_addr = vmx_get_untagged_addr, }; static unsigned int vmx_handle_intel_pt_intr(void) |