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-rw-r--r--arch/arm64/kernel/head.S7
-rw-r--r--arch/arm64/mm/hugetlbpage.c5
-rw-r--r--arch/arm64/mm/pageattr.c3
-rw-r--r--arch/powerpc/crypto/chacha-p10-glue.c8
-rw-r--r--arch/powerpc/kernel/iommu.c7
-rw-r--r--arch/s390/kernel/entry.S3
-rw-r--r--arch/x86/entry/common.c65
-rw-r--r--arch/x86/entry/entry_fred.c10
-rw-r--r--arch/x86/events/intel/lbr.c1
-rw-r--r--arch/x86/include/asm/kvm_host.h1
-rw-r--r--arch/x86/include/asm/perf_event.h1
-rw-r--r--arch/x86/kernel/cpu/bugs.c11
-rw-r--r--arch/x86/kernel/cpu/cpuid-deps.c6
-rw-r--r--arch/x86/kvm/Makefile5
-rw-r--r--arch/x86/kvm/cpuid.c1
-rw-r--r--arch/x86/kvm/cpuid.h10
-rw-r--r--arch/x86/kvm/lapic.c3
-rw-r--r--arch/x86/kvm/mmu/mmu.c11
-rw-r--r--arch/x86/kvm/mmu/tdp_mmu.c51
-rw-r--r--arch/x86/kvm/pmu.c16
-rw-r--r--arch/x86/kvm/svm/sev.c2
-rw-r--r--arch/x86/kvm/svm/svm.c17
-rw-r--r--arch/x86/kvm/svm/svm.h3
-rw-r--r--arch/x86/kvm/svm/vmenter.S97
-rw-r--r--arch/x86/kvm/vmx/pmu_intel.c2
-rw-r--r--arch/x86/kvm/vmx/vmx.c41
-rw-r--r--arch/x86/kvm/vmx/vmx.h6
-rw-r--r--arch/x86/kvm/x86.c2
-rw-r--r--arch/x86/lib/retpoline.S7
29 files changed, 265 insertions, 137 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 06234c3a15f3d..cb68adcabe078 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -289,6 +289,11 @@ SYM_INNER_LABEL(init_el2, SYM_L_LOCAL)
adr_l x1, __hyp_text_end
adr_l x2, dcache_clean_poc
blr x2
+
+ mov_q x0, INIT_SCTLR_EL2_MMU_OFF
+ pre_disable_mmu_workaround
+ msr sctlr_el2, x0
+ isb
0:
mov_q x0, HCR_HOST_NVHE_FLAGS
@@ -323,13 +328,11 @@ SYM_INNER_LABEL(init_el2, SYM_L_LOCAL)
cbz x0, 2f
/* Set a sane SCTLR_EL1, the VHE way */
- pre_disable_mmu_workaround
msr_s SYS_SCTLR_EL12, x1
mov x2, #BOOT_CPU_FLAG_E2H
b 3f
2:
- pre_disable_mmu_workaround
msr sctlr_el1, x1
mov x2, xzr
3:
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 0f0e10bb0a954..b872b003a55f3 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -276,7 +276,10 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
pte_t *ptep = NULL;
pgdp = pgd_offset(mm, addr);
- p4dp = p4d_offset(pgdp, addr);
+ p4dp = p4d_alloc(mm, pgdp, addr);
+ if (!p4dp)
+ return NULL;
+
pudp = pud_alloc(mm, p4dp, addr);
if (!pudp)
return NULL;
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
index 0c4e3ecf989d4..0e270a1c51e64 100644
--- a/arch/arm64/mm/pageattr.c
+++ b/arch/arm64/mm/pageattr.c
@@ -219,9 +219,6 @@ bool kernel_page_present(struct page *page)
pte_t *ptep;
unsigned long addr = (unsigned long)page_address(page);
- if (!can_set_direct_map())
- return true;
-
pgdp = pgd_offset_k(addr);
if (pgd_none(READ_ONCE(*pgdp)))
return false;
diff --git a/arch/powerpc/crypto/chacha-p10-glue.c b/arch/powerpc/crypto/chacha-p10-glue.c
index 74fb86b0d2097..7c728755852e1 100644
--- a/arch/powerpc/crypto/chacha-p10-glue.c
+++ b/arch/powerpc/crypto/chacha-p10-glue.c
@@ -197,6 +197,9 @@ static struct skcipher_alg algs[] = {
static int __init chacha_p10_init(void)
{
+ if (!cpu_has_feature(CPU_FTR_ARCH_31))
+ return 0;
+
static_branch_enable(&have_p10);
return crypto_register_skciphers(algs, ARRAY_SIZE(algs));
@@ -204,10 +207,13 @@ static int __init chacha_p10_init(void)
static void __exit chacha_p10_exit(void)
{
+ if (!static_branch_likely(&have_p10))
+ return;
+
crypto_unregister_skciphers(algs, ARRAY_SIZE(algs));
}
-module_cpu_feature_match(PPC_MODULE_FEATURE_P10, chacha_p10_init);
+module_init(chacha_p10_init);
module_exit(chacha_p10_exit);
MODULE_DESCRIPTION("ChaCha and XChaCha stream ciphers (P10 accelerated)");
diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index 1185efebf032b..29a8c8e185851 100644
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -1285,15 +1285,14 @@ spapr_tce_platform_iommu_attach_dev(struct iommu_domain *platform_domain,
struct device *dev)
{
struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
- struct iommu_group *grp = iommu_group_get(dev);
struct iommu_table_group *table_group;
+ struct iommu_group *grp;
/* At first attach the ownership is already set */
- if (!domain) {
- iommu_group_put(grp);
+ if (!domain)
return 0;
- }
+ grp = iommu_group_get(dev);
table_group = iommu_group_get_iommudata(grp);
/*
* The domain being set to PLATFORM from earlier
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 3dc85638bc63b..6a1e0fbbaa15b 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -340,7 +340,8 @@ SYM_CODE_START(pgm_check_handler)
mvc __PT_LAST_BREAK(8,%r11),__LC_PGM_LAST_BREAK
stctg %c1,%c1,__PT_CR1(%r11)
#if IS_ENABLED(CONFIG_KVM)
- lg %r12,__LC_GMAP
+ ltg %r12,__LC_GMAP
+ jz 5f
clc __GMAP_ASCE(8,%r12), __PT_CR1(%r11)
jne 5f
BPENTER __SF_SIE_FLAGS(%r10),_TIF_ISOLATE_BP_GUEST
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index 6de50b80702e6..51cc9c7cb9bdc 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -255,6 +255,71 @@ __visible noinstr void do_int80_emulation(struct pt_regs *regs)
instrumentation_end();
syscall_exit_to_user_mode(regs);
}
+
+#ifdef CONFIG_X86_FRED
+/*
+ * A FRED-specific INT80 handler is warranted for the follwing reasons:
+ *
+ * 1) As INT instructions and hardware interrupts are separate event
+ * types, FRED does not preclude the use of vector 0x80 for external
+ * interrupts. As a result, the FRED setup code does not reserve
+ * vector 0x80 and calling int80_is_external() is not merely
+ * suboptimal but actively incorrect: it could cause a system call
+ * to be incorrectly ignored.
+ *
+ * 2) It is called only for handling vector 0x80 of event type
+ * EVENT_TYPE_SWINT and will never be called to handle any external
+ * interrupt (event type EVENT_TYPE_EXTINT).
+ *
+ * 3) FRED has separate entry flows depending on if the event came from
+ * user space or kernel space, and because the kernel does not use
+ * INT insns, the FRED kernel entry handler fred_entry_from_kernel()
+ * falls through to fred_bad_type() if the event type is
+ * EVENT_TYPE_SWINT, i.e., INT insns. So if the kernel is handling
+ * an INT insn, it can only be from a user level.
+ *
+ * 4) int80_emulation() does a CLEAR_BRANCH_HISTORY. While FRED will
+ * likely take a different approach if it is ever needed: it
+ * probably belongs in either fred_intx()/ fred_other() or
+ * asm_fred_entrypoint_user(), depending on if this ought to be done
+ * for all entries from userspace or only system
+ * calls.
+ *
+ * 5) INT $0x80 is the fast path for 32-bit system calls under FRED.
+ */
+DEFINE_FREDENTRY_RAW(int80_emulation)
+{
+ int nr;
+
+ enter_from_user_mode(regs);
+
+ instrumentation_begin();
+ add_random_kstack_offset();
+
+ /*
+ * FRED pushed 0 into regs::orig_ax and regs::ax contains the
+ * syscall number.
+ *
+ * User tracing code (ptrace or signal handlers) might assume
+ * that the regs::orig_ax contains a 32-bit number on invoking
+ * a 32-bit syscall.
+ *
+ * Establish the syscall convention by saving the 32bit truncated
+ * syscall number in regs::orig_ax and by invalidating regs::ax.
+ */
+ regs->orig_ax = regs->ax & GENMASK(31, 0);
+ regs->ax = -ENOSYS;
+
+ nr = syscall_32_enter(regs);
+
+ local_irq_enable();
+ nr = syscall_enter_from_user_mode_work(regs, nr);
+ do_syscall_32_irqs_on(regs, nr);
+
+ instrumentation_end();
+ syscall_exit_to_user_mode(regs);
+}
+#endif
#else /* CONFIG_IA32_EMULATION */
/* Handles int $0x80 on a 32bit kernel */
diff --git a/arch/x86/entry/entry_fred.c b/arch/x86/entry/entry_fred.c
index ac120cbdaaf2b..89c1476fcdd9f 100644
--- a/arch/x86/entry/entry_fred.c
+++ b/arch/x86/entry/entry_fred.c
@@ -28,9 +28,9 @@ static noinstr void fred_bad_type(struct pt_regs *regs, unsigned long error_code
if (regs->fred_cs.sl > 0) {
pr_emerg("PANIC: invalid or fatal FRED event; event type %u "
"vector %u error 0x%lx aux 0x%lx at %04x:%016lx\n",
- regs->fred_ss.type, regs->fred_ss.vector, regs->orig_ax,
+ regs->fred_ss.type, regs->fred_ss.vector, error_code,
fred_event_data(regs), regs->cs, regs->ip);
- die("invalid or fatal FRED event", regs, regs->orig_ax);
+ die("invalid or fatal FRED event", regs, error_code);
panic("invalid or fatal FRED event");
} else {
unsigned long flags = oops_begin();
@@ -38,10 +38,10 @@ static noinstr void fred_bad_type(struct pt_regs *regs, unsigned long error_code
pr_alert("BUG: invalid or fatal FRED event; event type %u "
"vector %u error 0x%lx aux 0x%lx at %04x:%016lx\n",
- regs->fred_ss.type, regs->fred_ss.vector, regs->orig_ax,
+ regs->fred_ss.type, regs->fred_ss.vector, error_code,
fred_event_data(regs), regs->cs, regs->ip);
- if (__die("Invalid or fatal FRED event", regs, regs->orig_ax))
+ if (__die("Invalid or fatal FRED event", regs, error_code))
sig = 0;
oops_end(flags, regs, sig);
@@ -66,7 +66,7 @@ static noinstr void fred_intx(struct pt_regs *regs)
/* INT80 */
case IA32_SYSCALL_VECTOR:
if (ia32_enabled())
- return int80_emulation(regs);
+ return fred_int80_emulation(regs);
fallthrough;
#endif
diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c
index 78cd5084104e9..4367aa77cb8d9 100644
--- a/arch/x86/events/intel/lbr.c
+++ b/arch/x86/events/intel/lbr.c
@@ -1693,6 +1693,7 @@ void x86_perf_get_lbr(struct x86_pmu_lbr *lbr)
lbr->from = x86_pmu.lbr_from;
lbr->to = x86_pmu.lbr_to;
lbr->info = x86_pmu.lbr_info;
+ lbr->has_callstack = x86_pmu_has_lbr_callstack();
}
EXPORT_SYMBOL_GPL(x86_perf_get_lbr);
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 16e07a2eee195..6efd1497b0263 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -855,6 +855,7 @@ struct kvm_vcpu_arch {
int cpuid_nent;
struct kvm_cpuid_entry2 *cpuid_entries;
struct kvm_hypervisor_cpuid kvm_cpuid;
+ bool is_amd_compatible;
/*
* FIXME: Drop this macro and use KVM_NR_GOVERNED_FEATURES directly
diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index 3736b8a46c04d..7f1e17250546b 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -555,6 +555,7 @@ struct x86_pmu_lbr {
unsigned int from;
unsigned int to;
unsigned int info;
+ bool has_callstack;
};
extern void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap);
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index ca295b0c1eeee..ab18185894dfd 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -1652,7 +1652,8 @@ static void __init bhi_select_mitigation(void)
return;
/* Retpoline mitigates against BHI unless the CPU has RRSBA behavior */
- if (cpu_feature_enabled(X86_FEATURE_RETPOLINE)) {
+ if (boot_cpu_has(X86_FEATURE_RETPOLINE) &&
+ !boot_cpu_has(X86_FEATURE_RETPOLINE_LFENCE)) {
spec_ctrl_disable_kernel_rrsba();
if (rrsba_disabled)
return;
@@ -2804,11 +2805,13 @@ static const char *spectre_bhi_state(void)
{
if (!boot_cpu_has_bug(X86_BUG_BHI))
return "; BHI: Not affected";
- else if (boot_cpu_has(X86_FEATURE_CLEAR_BHB_HW))
+ else if (boot_cpu_has(X86_FEATURE_CLEAR_BHB_HW))
return "; BHI: BHI_DIS_S";
- else if (boot_cpu_has(X86_FEATURE_CLEAR_BHB_LOOP))
+ else if (boot_cpu_has(X86_FEATURE_CLEAR_BHB_LOOP))
return "; BHI: SW loop, KVM: SW loop";
- else if (boot_cpu_has(X86_FEATURE_RETPOLINE) && rrsba_disabled)
+ else if (boot_cpu_has(X86_FEATURE_RETPOLINE) &&
+ !boot_cpu_has(X86_FEATURE_RETPOLINE_LFENCE) &&
+ rrsba_disabled)
return "; BHI: Retpoline";
else if (boot_cpu_has(X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT))
return "; BHI: Vulnerable, KVM: SW loop";
diff --git a/arch/x86/kernel/cpu/cpuid-deps.c b/arch/x86/kernel/cpu/cpuid-deps.c
index b7174209d855c..946813d816bfc 100644
--- a/arch/x86/kernel/cpu/cpuid-deps.c
+++ b/arch/x86/kernel/cpu/cpuid-deps.c
@@ -44,7 +44,10 @@ static const struct cpuid_dep cpuid_deps[] = {
{ X86_FEATURE_F16C, X86_FEATURE_XMM2, },
{ X86_FEATURE_AES, X86_FEATURE_XMM2 },
{ X86_FEATURE_SHA_NI, X86_FEATURE_XMM2 },
+ { X86_FEATURE_GFNI, X86_FEATURE_XMM2 },
{ X86_FEATURE_FMA, X86_FEATURE_AVX },
+ { X86_FEATURE_VAES, X86_FEATURE_AVX },
+ { X86_FEATURE_VPCLMULQDQ, X86_FEATURE_AVX },
{ X86_FEATURE_AVX2, X86_FEATURE_AVX, },
{ X86_FEATURE_AVX512F, X86_FEATURE_AVX, },
{ X86_FEATURE_AVX512IFMA, X86_FEATURE_AVX512F },
@@ -56,9 +59,6 @@ static const struct cpuid_dep cpuid_deps[] = {
{ X86_FEATURE_AVX512VL, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512VBMI, X86_FEATURE_AVX512F },
{ X86_FEATURE_AVX512_VBMI2, X86_FEATURE_AVX512VL },
- { X86_FEATURE_GFNI, X86_FEATURE_AVX512VL },
- { X86_FEATURE_VAES, X86_FEATURE_AVX512VL },
- { X86_FEATURE_VPCLMULQDQ, X86_FEATURE_AVX512VL },
{ X86_FEATURE_AVX512_VNNI, X86_FEATURE_AVX512VL },
{ X86_FEATURE_AVX512_BITALG, X86_FEATURE_AVX512VL },
{ X86_FEATURE_AVX512_4VNNIW, X86_FEATURE_AVX512F },
diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index a88bb14266b69..addc44fc7187d 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -3,11 +3,6 @@
ccflags-y += -I $(srctree)/arch/x86/kvm
ccflags-$(CONFIG_KVM_WERROR) += -Werror
-ifeq ($(CONFIG_FRAME_POINTER),y)
-OBJECT_FILES_NON_STANDARD_vmx/vmenter.o := y
-OBJECT_FILES_NON_STANDARD_svm/vmenter.o := y
-endif
-
include $(srctree)/virt/kvm/Makefile.kvm
kvm-y += x86.o emulate.o i8259.o irq.o lapic.o \
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index bfc0bfcb2bc60..77352a4abd87f 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -376,6 +376,7 @@ static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
kvm_update_pv_runtime(vcpu);
+ vcpu->arch.is_amd_compatible = guest_cpuid_is_amd_or_hygon(vcpu);
vcpu->arch.maxphyaddr = cpuid_query_maxphyaddr(vcpu);
vcpu->arch.reserved_gpa_bits = kvm_vcpu_reserved_gpa_bits_raw(vcpu);
diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
index 856e3037e74f3..23dbb9eb277c7 100644
--- a/arch/x86/kvm/cpuid.h
+++ b/arch/x86/kvm/cpuid.h
@@ -120,6 +120,16 @@ static inline bool guest_cpuid_is_intel(struct kvm_vcpu *vcpu)
return best && is_guest_vendor_intel(best->ebx, best->ecx, best->edx);
}
+static inline bool guest_cpuid_is_amd_compatible(struct kvm_vcpu *vcpu)
+{
+ return vcpu->arch.is_amd_compatible;
+}
+
+static inline bool guest_cpuid_is_intel_compatible(struct kvm_vcpu *vcpu)
+{
+ return !guest_cpuid_is_amd_compatible(vcpu);
+}
+
static inline int guest_cpuid_family(struct kvm_vcpu *vcpu)
{
struct kvm_cpuid_entry2 *best;
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index cf37586f04668..ebf41023be382 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2776,7 +2776,8 @@ int kvm_apic_local_deliver(struct kvm_lapic *apic, int lvt_type)
trig_mode = reg & APIC_LVT_LEVEL_TRIGGER;
r = __apic_accept_irq(apic, mode, vector, 1, trig_mode, NULL);
- if (r && lvt_type == APIC_LVTPC)
+ if (r && lvt_type == APIC_LVTPC &&
+ guest_cpuid_is_intel_compatible(apic->vcpu))
kvm_lapic_set_reg(apic, APIC_LVTPC, reg | APIC_LVT_MASKED);
return r;
}
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 992e651540e85..db007a4dffa2e 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -4935,7 +4935,7 @@ static void reset_guest_rsvds_bits_mask(struct kvm_vcpu *vcpu,
context->cpu_role.base.level, is_efer_nx(context),
guest_can_use(vcpu, X86_FEATURE_GBPAGES),
is_cr4_pse(context),
- guest_cpuid_is_amd_or_hygon(vcpu));
+ guest_cpuid_is_amd_compatible(vcpu));
}
static void __reset_rsvds_bits_mask_ept(struct rsvd_bits_validate *rsvd_check,
@@ -5576,9 +5576,9 @@ void kvm_mmu_after_set_cpuid(struct kvm_vcpu *vcpu)
* that problem is swept under the rug; KVM's CPUID API is horrific and
* it's all but impossible to solve it without introducing a new API.
*/
- vcpu->arch.root_mmu.root_role.word = 0;
- vcpu->arch.guest_mmu.root_role.word = 0;
- vcpu->arch.nested_mmu.root_role.word = 0;
+ vcpu->arch.root_mmu.root_role.invalid = 1;
+ vcpu->arch.guest_mmu.root_role.invalid = 1;
+ vcpu->arch.nested_mmu.root_role.invalid = 1;
vcpu->arch.root_mmu.cpu_role.ext.valid = 0;
vcpu->arch.guest_mmu.cpu_role.ext.valid = 0;
vcpu->arch.nested_mmu.cpu_role.ext.valid = 0;
@@ -7399,7 +7399,8 @@ bool kvm_arch_post_set_memory_attributes(struct kvm *kvm,
* by the memslot, KVM can't use a hugepage due to the
* misaligned address regardless of memory attributes.
*/
- if (gfn >= slot->base_gfn) {
+ if (gfn >= slot->base_gfn &&
+ gfn + nr_pages <= slot->base_gfn + slot->npages) {
if (hugepage_has_attrs(kvm, slot, gfn, level, attrs))
hugepage_clear_mixed(slot, gfn, level);
else
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index d078157e62aa4..04c1f0957fea8 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -1548,17 +1548,21 @@ void kvm_tdp_mmu_try_split_huge_pages(struct kvm *kvm,
}
}
-/*
- * Clear the dirty status of all the SPTEs mapping GFNs in the memslot. If
- * AD bits are enabled, this will involve clearing the dirty bit on each SPTE.
- * If AD bits are not enabled, this will require clearing the writable bit on
- * each SPTE. Returns true if an SPTE has been changed and the TLBs need to
- * be flushed.
- */
+static bool tdp_mmu_need_write_protect(struct kvm_mmu_page *sp)
+{
+ /*
+ * All TDP MMU shadow pages share the same role as their root, aside
+ * from level, so it is valid to key off any shadow page to determine if
+ * write protection is needed for an entire tree.
+ */
+ return kvm_mmu_page_ad_need_write_protect(sp) || !kvm_ad_enabled();
+}
+
static bool clear_dirty_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root,
gfn_t start, gfn_t end)
{
- u64 dbit = kvm_ad_enabled() ? shadow_dirty_mask : PT_WRITABLE_MASK;
+ const u64 dbit = tdp_mmu_need_write_protect(root) ? PT_WRITABLE_MASK :
+ shadow_dirty_mask;
struct tdp_iter iter;
bool spte_set = false;
@@ -1573,7 +1577,7 @@ retry:
if (tdp_mmu_iter_cond_resched(kvm, &iter, false, true))
continue;
- KVM_MMU_WARN_ON(kvm_ad_enabled() &&
+ KVM_MMU_WARN_ON(dbit == shadow_dirty_mask &&
spte_ad_need_write_protect(iter.old_spte));
if (!(iter.old_spte & dbit))
@@ -1590,11 +1594,9 @@ retry:
}
/*
- * Clear the dirty status of all the SPTEs mapping GFNs in the memslot. If
- * AD bits are enabled, this will involve clearing the dirty bit on each SPTE.
- * If AD bits are not enabled, this will require clearing the writable bit on
- * each SPTE. Returns true if an SPTE has been changed and the TLBs need to
- * be flushed.
+ * Clear the dirty status (D-bit or W-bit) of all the SPTEs mapping GFNs in the
+ * memslot. Returns true if an SPTE has been changed and the TLBs need to be
+ * flushed.
*/
bool kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm,
const struct kvm_memory_slot *slot)
@@ -1610,18 +1612,11 @@ bool kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm,
return spte_set;
}
-/*
- * Clears the dirty status of all the 4k SPTEs mapping GFNs for which a bit is
- * set in mask, starting at gfn. The given memslot is expected to contain all
- * the GFNs represented by set bits in the mask. If AD bits are enabled,
- * clearing the dirty status will involve clearing the dirty bit on each SPTE
- * or, if AD bits are not enabled, clearing the writable bit on each SPTE.
- */
static void clear_dirty_pt_masked(struct kvm *kvm, struct kvm_mmu_page *root,
gfn_t gfn, unsigned long mask, bool wrprot)
{
- u64 dbit = (wrprot || !kvm_ad_enabled()) ? PT_WRITABLE_MASK :
- shadow_dirty_mask;
+ const u64 dbit = (wrprot || tdp_mmu_need_write_protect(root)) ? PT_WRITABLE_MASK :
+ shadow_dirty_mask;
struct tdp_iter iter;
lockdep_assert_held_write(&kvm->mmu_lock);
@@ -1633,7 +1628,7 @@ static void clear_dirty_pt_masked(struct kvm *kvm, struct kvm_mmu_page *root,
if (!mask)
break;
- KVM_MMU_WARN_ON(kvm_ad_enabled() &&
+ KVM_MMU_WARN_ON(dbit == shadow_dirty_mask &&
spte_ad_need_write_protect(iter.old_spte));
if (iter.level > PG_LEVEL_4K ||
@@ -1659,11 +1654,9 @@ static void clear_dirty_pt_masked(struct kvm *kvm, struct kvm_mmu_page *root,
}
/*
- * Clears the dirty status of all the 4k SPTEs mapping GFNs for which a bit is
- * set in mask, starting at gfn. The given memslot is expected to contain all
- * the GFNs represented by set bits in the mask. If AD bits are enabled,
- * clearing the dirty status will involve clearing the dirty bit on each SPTE
- * or, if AD bits are not enabled, clearing the writable bit on each SPTE.
+ * Clear the dirty status (D-bit or W-bit) of all the 4k SPTEs mapping GFNs for
+ * which a bit is set in mask, starting at gfn. The given memslot is expected to
+ * contain all the GFNs represented by set bits in the mask.
*/
void kvm_tdp_mmu_clear_dirty_pt_masked(struct kvm *kvm,
struct kvm_memory_slot *slot,
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index c397b28e3d1b6..a593b03c9aed6 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -775,8 +775,20 @@ void kvm_pmu_refresh(struct kvm_vcpu *vcpu)
pmu->pebs_data_cfg_mask = ~0ull;
bitmap_zero(pmu->all_valid_pmc_idx, X86_PMC_IDX_MAX);
- if (vcpu->kvm->arch.enable_pmu)
- static_call(kvm_x86_pmu_refresh)(vcpu);
+ if (!vcpu->kvm->arch.enable_pmu)
+ return;
+
+ static_call(kvm_x86_pmu_refresh)(vcpu);
+
+ /*
+ * At RESET, both Intel and AMD CPUs set all enable bits for general
+ * purpose counters in IA32_PERF_GLOBAL_CTRL (so that software that
+ * was written for v1 PMUs don't unknowingly leave GP counters disabled
+ * in the global controls). Emulate that behavior when refreshing the
+ * PMU so that userspace doesn't need to manually set PERF_GLOBAL_CTRL.
+ */
+ if (kvm_pmu_has_perf_global_ctrl(pmu) && pmu->nr_arch_gp_counters)
+ pmu->global_ctrl = GENMASK_ULL(pmu->nr_arch_gp_counters - 1, 0);
}
void kvm_pmu_init(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 61a7531d41b01..759581bb2128d 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -434,7 +434,7 @@ static struct page **sev_pin_memory(struct kvm *kvm, unsigned long uaddr,
/* Avoid using vmalloc for smaller buffers. */
size = npages * sizeof(struct page *);
if (size > PAGE_SIZE)
- pages = __vmalloc(size, GFP_KERNEL_ACCOUNT | __GFP_ZERO);
+ pages = __vmalloc(size, GFP_KERNEL_ACCOUNT);
else
pages = kmalloc(size, GFP_KERNEL_ACCOUNT);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index d1a9f99516358..9aaf83c8d57df 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1503,6 +1503,11 @@ static void svm_vcpu_free(struct kvm_vcpu *vcpu)
__free_pages(virt_to_page(svm->msrpm), get_order(MSRPM_SIZE));
}
+static struct sev_es_save_area *sev_es_host_save_area(struct svm_cpu_data *sd)
+{
+ return page_address(sd->save_area) + 0x400;
+}
+
static void svm_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
@@ -1519,12 +1524,8 @@ static void svm_prepare_switch_to_guest(struct kvm_vcpu *vcpu)
* or subsequent vmload of host save area.
*/
vmsave(sd->save_area_pa);
- if (sev_es_guest(vcpu->kvm)) {
- struct sev_es_save_area *hostsa;
- hostsa = (struct sev_es_save_area *)(page_address(sd->save_area) + 0x400);
-
- sev_es_prepare_switch_to_guest(hostsa);
- }
+ if (sev_es_guest(vcpu->kvm))
+ sev_es_prepare_switch_to_guest(sev_es_host_save_area(sd));
if (tsc_scaling)
__svm_write_tsc_multiplier(vcpu->arch.tsc_scaling_ratio);
@@ -4101,6 +4102,7 @@ static fastpath_t svm_exit_handlers_fastpath(struct kvm_vcpu *vcpu)
static noinstr void svm_vcpu_enter_exit(struct kvm_vcpu *vcpu, bool spec_ctrl_intercepted)
{
+ struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, vcpu->cpu);
struct vcpu_svm *svm = to_svm(vcpu);
guest_state_enter_irqoff();
@@ -4108,7 +4110,8 @@ static noinstr void svm_vcpu_enter_exit(struct kvm_vcpu *vcpu, bool spec_ctrl_in
amd_clear_divider();
if (sev_es_guest(vcpu->kvm))
- __svm_sev_es_vcpu_run(svm, spec_ctrl_intercepted);
+ __svm_sev_es_vcpu_run(svm, spec_ctrl_intercepted,
+ sev_es_host_save_area(sd));
else
__svm_vcpu_run(svm, spec_ctrl_intercepted);
diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 7f1fbd874c458..33878efdebc82 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -698,7 +698,8 @@ struct page *snp_safe_alloc_page(struct kvm_vcpu *vcpu);
/* vmenter.S */
-void __svm_sev_es_vcpu_run(struct vcpu_svm *svm, bool spec_ctrl_intercepted);
+void __svm_sev_es_vcpu_run(struct vcpu_svm *svm, bool spec_ctrl_intercepted,
+ struct sev_es_save_area *hostsa);
void __svm_vcpu_run(struct vcpu_svm *svm, bool spec_ctrl_intercepted);
#define DEFINE_KVM_GHCB_ACCESSORS(field) \
diff --git a/arch/x86/kvm/svm/vmenter.S b/arch/x86/kvm/svm/vmenter.S
index 187018c424bfb..a0c8eb37d3e1c 100644
--- a/arch/x86/kvm/svm/vmenter.S
+++ b/arch/x86/kvm/svm/vmenter.S
@@ -3,6 +3,7 @@
#include <asm/asm.h>
#include <asm/asm-offsets.h>
#include <asm/bitsperlong.h>
+#include <asm/frame.h>
#include <asm/kvm_vcpu_regs.h>
#include <asm/nospec-branch.h>
#include "kvm-asm-offsets.h"
@@ -67,7 +68,7 @@
"", X86_FEATURE_V_SPEC_CTRL
901:
.endm
-.macro RESTORE_HOST_SPEC_CTRL_BODY
+.macro RESTORE_HOST_SPEC_CTRL_BODY spec_ctrl_intercepted:req
900:
/* Same for after vmexit. */
mov $MSR_IA32_SPEC_CTRL, %ecx
@@ -76,7 +77,7 @@
* Load the value that the guest had written into MSR_IA32_SPEC_CTRL,
* if it was not intercepted during guest execution.
*/
- cmpb $0, (%_ASM_SP)
+ cmpb $0, \spec_ctrl_intercepted
jnz 998f
rdmsr
movl %eax, SVM_spec_ctrl(%_ASM_DI)
@@ -99,6 +100,7 @@
*/
SYM_FUNC_START(__svm_vcpu_run)
push %_ASM_BP
+ mov %_ASM_SP, %_ASM_BP
#ifdef CONFIG_X86_64
push %r15
push %r14
@@ -268,7 +270,7 @@ SYM_FUNC_START(__svm_vcpu_run)
RET
RESTORE_GUEST_SPEC_CTRL_BODY
- RESTORE_HOST_SPEC_CTRL_BODY
+ RESTORE_HOST_SPEC_CTRL_BODY (%_ASM_SP)
10: cmpb $0, _ASM_RIP(kvm_rebooting)
jne 2b
@@ -290,66 +292,68 @@ SYM_FUNC_START(__svm_vcpu_run)
SYM_FUNC_END(__svm_vcpu_run)
+#ifdef CONFIG_KVM_AMD_SEV
+
+
+#ifdef CONFIG_X86_64
+#define SEV_ES_GPRS_BASE 0x300
+#define SEV_ES_RBX (SEV_ES_GPRS_BASE + __VCPU_REGS_RBX * WORD_SIZE)
+#define SEV_ES_RBP (SEV_ES_GPRS_BASE + __VCPU_REGS_RBP * WORD_SIZE)
+#define SEV_ES_RSI (SEV_ES_GPRS_BASE + __VCPU_REGS_RSI * WORD_SIZE)
+#define SEV_ES_RDI (SEV_ES_GPRS_BASE + __VCPU_REGS_RDI * WORD_SIZE)
+#define SEV_ES_R12 (SEV_ES_GPRS_BASE + __VCPU_REGS_R12 * WORD_SIZE)
+#define SEV_ES_R13 (SEV_ES_GPRS_BASE + __VCPU_REGS_R13 * WORD_SIZE)
+#define SEV_ES_R14 (SEV_ES_GPRS_BASE + __VCPU_REGS_R14 * WORD_SIZE)
+#define SEV_ES_R15 (SEV_ES_GPRS_BASE + __VCPU_REGS_R15 * WORD_SIZE)
+#endif
+
/**
* __svm_sev_es_vcpu_run - Run a SEV-ES vCPU via a transition to SVM guest mode
* @svm: struct vcpu_svm *
* @spec_ctrl_intercepted: bool
*/
SYM_FUNC_START(__svm_sev_es_vcpu_run)
- push %_ASM_BP
-#ifdef CONFIG_X86_64
- push %r15
- push %r14
- push %r13
- push %r12
-#else
- push %edi
- push %esi
-#endif
- push %_ASM_BX
+ FRAME_BEGIN
/*
- * Save variables needed after vmexit on the stack, in inverse
- * order compared to when they are needed.
+ * Save non-volatile (callee-saved) registers to the host save area.
+ * Except for RAX and RSP, all GPRs are restored on #VMEXIT, but not
+ * saved on VMRUN.
*/
+ mov %rbp, SEV_ES_RBP (%rdx)
+ mov %r15, SEV_ES_R15 (%rdx)
+ mov %r14, SEV_ES_R14 (%rdx)
+ mov %r13, SEV_ES_R13 (%rdx)
+ mov %r12, SEV_ES_R12 (%rdx)
+ mov %rbx, SEV_ES_RBX (%rdx)
- /* Accessed directly from the stack in RESTORE_HOST_SPEC_CTRL. */
- push %_ASM_ARG2
-
- /* Save @svm. */
- push %_ASM_ARG1
-
-.ifnc _ASM_ARG1, _ASM_DI
/*
- * Stash @svm in RDI early. On 32-bit, arguments are in RAX, RCX
- * and RDX which are clobbered by RESTORE_GUEST_SPEC_CTRL.
+ * Save volatile registers that hold arguments that are needed after
+ * #VMEXIT (RDI=@svm and RSI=@spec_ctrl_intercepted).
*/
- mov %_ASM_ARG1, %_ASM_DI
-.endif
+ mov %rdi, SEV_ES_RDI (%rdx)
+ mov %rsi, SEV_ES_RSI (%rdx)
- /* Clobbers RAX, RCX, RDX. */
+ /* Clobbers RAX, RCX, RDX (@hostsa). */
RESTORE_GUEST_SPEC_CTRL
/* Get svm->current_vmcb->pa into RAX. */
- mov SVM_current_vmcb(%_ASM_DI), %_ASM_AX
- mov KVM_VMCB_pa(%_ASM_AX), %_ASM_AX
+ mov SVM_current_vmcb(%rdi), %rax
+ mov KVM_VMCB_pa(%rax), %rax
/* Enter guest mode */
sti
-1: vmrun %_ASM_AX
+1: vmrun %rax
2: cli
- /* Pop @svm to RDI, guest registers have been saved already. */
- pop %_ASM_DI
-
#ifdef CONFIG_MITIGATION_RETPOLINE
/* IMPORTANT: Stuff the RSB immediately after VM-Exit, before RET! */
- FILL_RETURN_BUFFER %_ASM_AX, RSB_CLEAR_LOOPS, X86_FEATURE_RETPOLINE
+ FILL_RETURN_BUFFER %rax, RSB_CLEAR_LOOPS, X86_FEATURE_RETPOLINE
#endif
- /* Clobbers RAX, RCX, RDX. */
+ /* Clobbers RAX, RCX, RDX, consumes RDI (@svm) and RSI (@spec_ctrl_intercepted). */
RESTORE_HOST_SPEC_CTRL
/*
@@ -361,30 +365,17 @@ SYM_FUNC_START(__svm_sev_es_vcpu_run)
*/
UNTRAIN_RET_VM
- /* "Pop" @spec_ctrl_intercepted. */
- pop %_ASM_BX
-
- pop %_ASM_BX
-
-#ifdef CONFIG_X86_64
- pop %r12
- pop %r13
- pop %r14
- pop %r15
-#else
- pop %esi
- pop %edi
-#endif
- pop %_ASM_BP
+ FRAME_END
RET
RESTORE_GUEST_SPEC_CTRL_BODY
- RESTORE_HOST_SPEC_CTRL_BODY
+ RESTORE_HOST_SPEC_CTRL_BODY %sil
-3: cmpb $0, _ASM_RIP(kvm_rebooting)
+3: cmpb $0, kvm_rebooting(%rip)
jne 2b
ud2
_ASM_EXTABLE(1b, 3b)
SYM_FUNC_END(__svm_sev_es_vcpu_run)
+#endif /* CONFIG_KVM_AMD_SEV */
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index 12ade343a17ed..be40474de6e4d 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -535,7 +535,7 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
perf_capabilities = vcpu_get_perf_capabilities(vcpu);
if (cpuid_model_is_consistent(vcpu) &&
(perf_capabilities & PMU_CAP_LBR_FMT))
- x86_perf_get_lbr(&lbr_desc->records);
+ memcpy(&lbr_desc->records, &vmx_lbr_caps, sizeof(vmx_lbr_caps));
else
lbr_desc->records.nr = 0;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index c37a89eda90f8..22411f4aff530 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -218,6 +218,8 @@ module_param(ple_window_max, uint, 0444);
int __read_mostly pt_mode = PT_MODE_SYSTEM;
module_param(pt_mode, int, S_IRUGO);
+struct x86_pmu_lbr __ro_after_init vmx_lbr_caps;
+
static DEFINE_STATIC_KEY_FALSE(vmx_l1d_should_flush);
static DEFINE_STATIC_KEY_FALSE(vmx_l1d_flush_cond);
static DEFINE_MUTEX(vmx_l1d_flush_mutex);
@@ -7862,10 +7864,9 @@ static void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu)
vmx_update_exception_bitmap(vcpu);
}
-static u64 vmx_get_perf_capabilities(void)
+static __init u64 vmx_get_perf_capabilities(void)
{
u64 perf_cap = PMU_CAP_FW_WRITES;
- struct x86_pmu_lbr lbr;
u64 host_perf_cap = 0;
if (!enable_pmu)
@@ -7875,15 +7876,43 @@ static u64 vmx_get_perf_capabilities(void)
rdmsrl(MSR_IA32_PERF_CAPABILITIES, host_perf_cap);
if (!cpu_feature_enabled(X86_FEATURE_ARCH_LBR)) {
- x86_perf_get_lbr(&lbr);
- if (lbr.nr)
+ x86_perf_get_lbr(&vmx_lbr_caps);
+
+ /*
+ * KVM requires LBR callstack support, as the overhead due to
+ * context switching LBRs without said support is too high.
+ * See intel_pmu_create_guest_lbr_event() for more info.
+ */
+ if (!vmx_lbr_caps.has_callstack)
+ memset(&vmx_lbr_caps, 0, sizeof(vmx_lbr_caps));
+ else if (vmx_lbr_caps.nr)
perf_cap |= host_perf_cap & PMU_CAP_LBR_FMT;
}
if (vmx_pebs_supported()) {
perf_cap |= host_perf_cap & PERF_CAP_PEBS_MASK;
- if ((perf_cap & PERF_CAP_PEBS_FORMAT) < 4)
- perf_cap &= ~PERF_CAP_PEBS_BASELINE;
+
+ /*
+ * Disallow adaptive PEBS as it is functionally broken, can be
+ * used by the guest to read *host* LBRs, and can be used to
+ * bypass userspace event filters. To correctly and safely
+ * support adaptive PEBS, KVM needs to:
+ *
+ * 1. Account for the ADAPTIVE flag when (re)programming fixed
+ * counters.
+ *
+ * 2. Gain support from perf (or take direct control of counter
+ * programming) to support events without adaptive PEBS
+ * enabled for the hardware counter.
+ *
+ * 3. Ensure LBR MSRs cannot hold host data on VM-Entry with
+ * adaptive PEBS enabled and MSR_PEBS_DATA_CFG.LBRS=1.
+ *
+ * 4. Document which PMU events are effectively exposed to the
+ * guest via adaptive PEBS, and make adaptive PEBS mutually
+ * exclusive with KVM_SET_PMU_EVENT_FILTER if necessary.
+ */
+ perf_cap &= ~PERF_CAP_PEBS_BASELINE;
}
return perf_cap;
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
index 65786dbe7d60b..90f9e44346464 100644
--- a/arch/x86/kvm/vmx/vmx.h
+++ b/arch/x86/kvm/vmx/vmx.h
@@ -15,6 +15,7 @@
#include "vmx_ops.h"
#include "../cpuid.h"
#include "run_flags.h"
+#include "../mmu.h"
#define MSR_TYPE_R 1
#define MSR_TYPE_W 2
@@ -109,6 +110,8 @@ struct lbr_desc {
bool msr_passthrough;
};
+extern struct x86_pmu_lbr vmx_lbr_caps;
+
/*
* The nested_vmx structure is part of vcpu_vmx, and holds information we need
* for correct emulation of VMX (i.e., nested VMX) on this vcpu.
@@ -719,7 +722,8 @@ static inline bool vmx_need_pf_intercept(struct kvm_vcpu *vcpu)
if (!enable_ept)
return true;
- return allow_smaller_maxphyaddr && cpuid_maxphyaddr(vcpu) < boot_cpu_data.x86_phys_bits;
+ return allow_smaller_maxphyaddr &&
+ cpuid_maxphyaddr(vcpu) < kvm_get_shadow_phys_bits();
}
static inline bool is_unrestricted_guest(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 984ea2089efc3..91478b769af08 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3470,7 +3470,7 @@ static bool is_mci_status_msr(u32 msr)
static bool can_set_mci_status(struct kvm_vcpu *vcpu)
{
/* McStatusWrEn enabled? */
- if (guest_cpuid_is_amd_or_hygon(vcpu))
+ if (guest_cpuid_is_amd_compatible(vcpu))
return !!(vcpu->arch.msr_hwcr & BIT_ULL(18));
return false;
diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S
index e674ccf720b9f..391059b2c6fbc 100644
--- a/arch/x86/lib/retpoline.S
+++ b/arch/x86/lib/retpoline.S
@@ -382,8 +382,15 @@ SYM_FUNC_END(call_depth_return_thunk)
SYM_CODE_START(__x86_return_thunk)
UNWIND_HINT_FUNC
ANNOTATE_NOENDBR
+#if defined(CONFIG_MITIGATION_UNRET_ENTRY) || \
+ defined(CONFIG_MITIGATION_SRSO) || \
+ defined(CONFIG_MITIGATION_CALL_DEPTH_TRACKING)
ALTERNATIVE __stringify(ANNOTATE_UNRET_SAFE; ret), \
"jmp warn_thunk_thunk", X86_FEATURE_ALWAYS
+#else
+ ANNOTATE_UNRET_SAFE
+ ret
+#endif
int3
SYM_CODE_END(__x86_return_thunk)
EXPORT_SYMBOL(__x86_return_thunk)