diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-11-12 22:34:06 (GMT) |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-11-12 22:34:06 (GMT) |
commit | 3370b69eb0c1f6a05f9051e8fc3e8768461a80f7 (patch) | |
tree | 722a75d9d3cc605bfd513752054dea1df806385d /arch/x86/kvm | |
parent | be23c9d20b341a58ad7107f9e9aa5735cea3da13 (diff) | |
parent | 370289756beccdc2a6ef9c7998fe67a7ca68bfc2 (diff) | |
download | linux-3370b69eb0c1f6a05f9051e8fc3e8768461a80f7.tar.xz |
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull second batch of kvm updates from Paolo Bonzini:
"Four changes:
- x86: work around two nasty cases where a benign exception occurs
while another is being delivered. The endless stream of exceptions
causes an infinite loop in the processor, which not even NMIs or
SMIs can interrupt; in the virt case, there is no possibility to
exit to the host either.
- x86: support for Skylake per-guest TSC rate. Long supported by
AMD, the patches mostly move things from there to common
arch/x86/kvm/ code.
- generic: remove local_irq_save/restore from the guest entry and
exit paths when context tracking is enabled. The patches are a few
months old, but we discussed them again at kernel summit. Andy
will pick up from here and, in 4.5, try to remove it from the user
entry/exit paths.
- PPC: Two bug fixes, see merge commit 370289756becc for details"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (21 commits)
KVM: x86: rename update_db_bp_intercept to update_bp_intercept
KVM: svm: unconditionally intercept #DB
KVM: x86: work around infinite loop in microcode when #AC is delivered
context_tracking: avoid irq_save/irq_restore on guest entry and exit
context_tracking: remove duplicate enabled check
KVM: VMX: Dump TSC multiplier in dump_vmcs()
KVM: VMX: Use a scaled host TSC for guest readings of MSR_IA32_TSC
KVM: VMX: Setup TSC scaling ratio when a vcpu is loaded
KVM: VMX: Enable and initialize VMX TSC scaling
KVM: x86: Use the correct vcpu's TSC rate to compute time scale
KVM: x86: Move TSC scaling logic out of call-back read_l1_tsc()
KVM: x86: Move TSC scaling logic out of call-back adjust_tsc_offset()
KVM: x86: Replace call-back compute_tsc_offset() with a common function
KVM: x86: Replace call-back set_tsc_khz() with a common function
KVM: x86: Add a common TSC scaling function
KVM: x86: Add a common TSC scaling ratio field in kvm_vcpu_arch
KVM: x86: Collect information for setting TSC scaling ratio
KVM: x86: declare a few variables as __read_mostly
KVM: x86: merge handle_mmio_page_fault and handle_mmio_page_fault_common
KVM: PPC: Book3S HV: Don't dynamically split core when already split
...
Diffstat (limited to 'arch/x86/kvm')
-rw-r--r-- | arch/x86/kvm/lapic.c | 4 | ||||
-rw-r--r-- | arch/x86/kvm/mmu.c | 20 | ||||
-rw-r--r-- | arch/x86/kvm/mmu.h | 6 | ||||
-rw-r--r-- | arch/x86/kvm/paging_tmpl.h | 3 | ||||
-rw-r--r-- | arch/x86/kvm/svm.c | 140 | ||||
-rw-r--r-- | arch/x86/kvm/vmx.c | 71 | ||||
-rw-r--r-- | arch/x86/kvm/x86.c | 159 |
7 files changed, 209 insertions, 194 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index ecd4ea1..4d30b86 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1250,7 +1250,7 @@ void wait_lapic_expire(struct kvm_vcpu *vcpu) tsc_deadline = apic->lapic_timer.expired_tscdeadline; apic->lapic_timer.expired_tscdeadline = 0; - guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, rdtsc()); + guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc()); trace_kvm_wait_lapic_expire(vcpu->vcpu_id, guest_tsc - tsc_deadline); /* __delay is delay_tsc whenever the hardware has TSC, thus always. */ @@ -1318,7 +1318,7 @@ static void start_apic_timer(struct kvm_lapic *apic) local_irq_save(flags); now = apic->lapic_timer.timer.base->get_time(); - guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, rdtsc()); + guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc()); if (likely(tscdeadline > guest_tsc)) { ns = (tscdeadline - guest_tsc) * 1000000ULL; do_div(ns, this_tsc_khz); diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 7d85bca..e7c2c14 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3359,7 +3359,7 @@ exit: return reserved; } -int handle_mmio_page_fault_common(struct kvm_vcpu *vcpu, u64 addr, bool direct) +int handle_mmio_page_fault(struct kvm_vcpu *vcpu, u64 addr, bool direct) { u64 spte; bool reserved; @@ -3368,7 +3368,7 @@ int handle_mmio_page_fault_common(struct kvm_vcpu *vcpu, u64 addr, bool direct) return RET_MMIO_PF_EMULATE; reserved = walk_shadow_page_get_mmio_spte(vcpu, addr, &spte); - if (unlikely(reserved)) + if (WARN_ON(reserved)) return RET_MMIO_PF_BUG; if (is_mmio_spte(spte)) { @@ -3392,17 +3392,7 @@ int handle_mmio_page_fault_common(struct kvm_vcpu *vcpu, u64 addr, bool direct) */ return RET_MMIO_PF_RETRY; } -EXPORT_SYMBOL_GPL(handle_mmio_page_fault_common); - -static int handle_mmio_page_fault(struct kvm_vcpu *vcpu, u64 addr, - u32 error_code, bool direct) -{ - int ret; - - ret = handle_mmio_page_fault_common(vcpu, addr, direct); - WARN_ON(ret == RET_MMIO_PF_BUG); - return ret; -} +EXPORT_SYMBOL_GPL(handle_mmio_page_fault); static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva, u32 error_code, bool prefault) @@ -3413,7 +3403,7 @@ static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva, pgprintk("%s: gva %lx error %x\n", __func__, gva, error_code); if (unlikely(error_code & PFERR_RSVD_MASK)) { - r = handle_mmio_page_fault(vcpu, gva, error_code, true); + r = handle_mmio_page_fault(vcpu, gva, true); if (likely(r != RET_MMIO_PF_INVALID)) return r; @@ -3503,7 +3493,7 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, u32 error_code, MMU_WARN_ON(!VALID_PAGE(vcpu->arch.mmu.root_hpa)); if (unlikely(error_code & PFERR_RSVD_MASK)) { - r = handle_mmio_page_fault(vcpu, gpa, error_code, true); + r = handle_mmio_page_fault(vcpu, gpa, true); if (likely(r != RET_MMIO_PF_INVALID)) return r; diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h index e4202e4..55ffb7b 100644 --- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -56,13 +56,13 @@ void reset_shadow_zero_bits_mask(struct kvm_vcpu *vcpu, struct kvm_mmu *context); /* - * Return values of handle_mmio_page_fault_common: + * Return values of handle_mmio_page_fault: * RET_MMIO_PF_EMULATE: it is a real mmio page fault, emulate the instruction * directly. * RET_MMIO_PF_INVALID: invalid spte is detected then let the real page * fault path update the mmio spte. * RET_MMIO_PF_RETRY: let CPU fault again on the address. - * RET_MMIO_PF_BUG: bug is detected. + * RET_MMIO_PF_BUG: a bug was detected (and a WARN was printed). */ enum { RET_MMIO_PF_EMULATE = 1, @@ -71,7 +71,7 @@ enum { RET_MMIO_PF_BUG = -1 }; -int handle_mmio_page_fault_common(struct kvm_vcpu *vcpu, u64 addr, bool direct); +int handle_mmio_page_fault(struct kvm_vcpu *vcpu, u64 addr, bool direct); void kvm_init_shadow_mmu(struct kvm_vcpu *vcpu); void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly); diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index b41faa9..3058a22 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -705,8 +705,7 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code, pgprintk("%s: addr %lx err %x\n", __func__, addr, error_code); if (unlikely(error_code & PFERR_RSVD_MASK)) { - r = handle_mmio_page_fault(vcpu, addr, error_code, - mmu_is_nested(vcpu)); + r = handle_mmio_page_fault(vcpu, addr, mmu_is_nested(vcpu)); if (likely(r != RET_MMIO_PF_INVALID)) return r; diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index f2c8e49..83a1c64 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -158,8 +158,6 @@ struct vcpu_svm { unsigned long int3_rip; u32 apf_reason; - u64 tsc_ratio; - /* cached guest cpuid flags for faster access */ bool nrips_enabled : 1; }; @@ -214,7 +212,6 @@ static int nested_svm_intercept(struct vcpu_svm *svm); static int nested_svm_vmexit(struct vcpu_svm *svm); static int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr, bool has_error_code, u32 error_code); -static u64 __scale_tsc(u64 ratio, u64 tsc); enum { VMCB_INTERCEPTS, /* Intercept vectors, TSC offset, @@ -894,20 +891,9 @@ static __init int svm_hardware_setup(void) kvm_enable_efer_bits(EFER_FFXSR); if (boot_cpu_has(X86_FEATURE_TSCRATEMSR)) { - u64 max; - kvm_has_tsc_control = true; - - /* - * Make sure the user can only configure tsc_khz values that - * fit into a signed integer. - * A min value is not calculated needed because it will always - * be 1 on all machines and a value of 0 is used to disable - * tsc-scaling for the vcpu. - */ - max = min(0x7fffffffULL, __scale_tsc(tsc_khz, TSC_RATIO_MAX)); - - kvm_max_guest_tsc_khz = max; + kvm_max_tsc_scaling_ratio = TSC_RATIO_MAX; + kvm_tsc_scaling_ratio_frac_bits = 32; } if (nested) { @@ -971,68 +957,6 @@ static void init_sys_seg(struct vmcb_seg *seg, uint32_t type) seg->base = 0; } -static u64 __scale_tsc(u64 ratio, u64 tsc) -{ - u64 mult, frac, _tsc; - - mult = ratio >> 32; - frac = ratio & ((1ULL << 32) - 1); - - _tsc = tsc; - _tsc *= mult; - _tsc += (tsc >> 32) * frac; - _tsc += ((tsc & ((1ULL << 32) - 1)) * frac) >> 32; - - return _tsc; -} - -static u64 svm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc) -{ - struct vcpu_svm *svm = to_svm(vcpu); - u64 _tsc = tsc; - - if (svm->tsc_ratio != TSC_RATIO_DEFAULT) - _tsc = __scale_tsc(svm->tsc_ratio, tsc); - - return _tsc; -} - -static void svm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz, bool scale) -{ - struct vcpu_svm *svm = to_svm(vcpu); - u64 ratio; - u64 khz; - - /* Guest TSC same frequency as host TSC? */ - if (!scale) { - svm->tsc_ratio = TSC_RATIO_DEFAULT; - return; - } - - /* TSC scaling supported? */ - if (!boot_cpu_has(X86_FEATURE_TSCRATEMSR)) { - if (user_tsc_khz > tsc_khz) { - vcpu->arch.tsc_catchup = 1; - vcpu->arch.tsc_always_catchup = 1; - } else - WARN(1, "user requested TSC rate below hardware speed\n"); - return; - } - - khz = user_tsc_khz; - - /* TSC scaling required - calculate ratio */ - ratio = khz << 32; - do_div(ratio, tsc_khz); - - if (ratio == 0 || ratio & TSC_RATIO_RSVD) { - WARN_ONCE(1, "Invalid TSC ratio - virtual-tsc-khz=%u\n", - user_tsc_khz); - return; - } - svm->tsc_ratio = ratio; -} - static u64 svm_read_tsc_offset(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); @@ -1059,16 +983,10 @@ static void svm_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset) mark_dirty(svm->vmcb, VMCB_INTERCEPTS); } -static void svm_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment, bool host) +static void svm_adjust_tsc_offset_guest(struct kvm_vcpu *vcpu, s64 adjustment) { struct vcpu_svm *svm = to_svm(vcpu); - if (host) { - if (svm->tsc_ratio != TSC_RATIO_DEFAULT) - WARN_ON(adjustment < 0); - adjustment = svm_scale_tsc(vcpu, (u64)adjustment); - } - svm->vmcb->control.tsc_offset += adjustment; if (is_guest_mode(vcpu)) svm->nested.hsave->control.tsc_offset += adjustment; @@ -1080,15 +998,6 @@ static void svm_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment, bool ho mark_dirty(svm->vmcb, VMCB_INTERCEPTS); } -static u64 svm_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc) -{ - u64 tsc; - - tsc = svm_scale_tsc(vcpu, rdtsc()); - - return target_tsc - tsc; -} - static void init_vmcb(struct vcpu_svm *svm) { struct vmcb_control_area *control = &svm->vmcb->control; @@ -1110,6 +1019,8 @@ static void init_vmcb(struct vcpu_svm *svm) set_exception_intercept(svm, PF_VECTOR); set_exception_intercept(svm, UD_VECTOR); set_exception_intercept(svm, MC_VECTOR); + set_exception_intercept(svm, AC_VECTOR); + set_exception_intercept(svm, DB_VECTOR); set_intercept(svm, INTERCEPT_INTR); set_intercept(svm, INTERCEPT_NMI); @@ -1235,8 +1146,6 @@ static struct kvm_vcpu *svm_create_vcpu(struct kvm *kvm, unsigned int id) goto out; } - svm->tsc_ratio = TSC_RATIO_DEFAULT; - err = kvm_vcpu_init(&svm->vcpu, kvm, id); if (err) goto free_svm; @@ -1322,10 +1231,12 @@ static void svm_vcpu_load(struct kvm_vcpu *vcpu, int cpu) for (i = 0; i < NR_HOST_SAVE_USER_MSRS; i++) rdmsrl(host_save_user_msrs[i], svm->host_user_msrs[i]); - if (static_cpu_has(X86_FEATURE_TSCRATEMSR) && - svm->tsc_ratio != __this_cpu_read(current_tsc_ratio)) { - __this_cpu_write(current_tsc_ratio, svm->tsc_ratio); - wrmsrl(MSR_AMD64_TSC_RATIO, svm->tsc_ratio); + if (static_cpu_has(X86_FEATURE_TSCRATEMSR)) { + u64 tsc_ratio = vcpu->arch.tsc_scaling_ratio; + if (tsc_ratio != __this_cpu_read(current_tsc_ratio)) { + __this_cpu_write(current_tsc_ratio, tsc_ratio); + wrmsrl(MSR_AMD64_TSC_RATIO, tsc_ratio); + } } } @@ -1644,20 +1555,13 @@ static void svm_set_segment(struct kvm_vcpu *vcpu, mark_dirty(svm->vmcb, VMCB_SEG); } -static void update_db_bp_intercept(struct kvm_vcpu *vcpu) +static void update_bp_intercept(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); - clr_exception_intercept(svm, DB_VECTOR); clr_exception_intercept(svm, BP_VECTOR); - if (svm->nmi_singlestep) - set_exception_intercept(svm, DB_VECTOR); - if (vcpu->guest_debug & KVM_GUESTDBG_ENABLE) { - if (vcpu->guest_debug & - (KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP)) - set_exception_intercept(svm, DB_VECTOR); if (vcpu->guest_debug & KVM_GUESTDBG_USE_SW_BP) set_exception_intercept(svm, BP_VECTOR); } else @@ -1763,7 +1667,6 @@ static int db_interception(struct vcpu_svm *svm) if (!(svm->vcpu.guest_debug & KVM_GUESTDBG_SINGLESTEP)) svm->vmcb->save.rflags &= ~(X86_EFLAGS_TF | X86_EFLAGS_RF); - update_db_bp_intercept(&svm->vcpu); } if (svm->vcpu.guest_debug & @@ -1798,6 +1701,12 @@ static int ud_interception(struct vcpu_svm *svm) return 1; } +static int ac_interception(struct vcpu_svm *svm) +{ + kvm_queue_exception_e(&svm->vcpu, AC_VECTOR, 0); + return 1; +} + static void svm_fpu_activate(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); @@ -3075,8 +2984,7 @@ static int cr8_write_interception(struct vcpu_svm *svm) static u64 svm_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc) { struct vmcb *vmcb = get_host_vmcb(to_svm(vcpu)); - return vmcb->control.tsc_offset + - svm_scale_tsc(vcpu, host_tsc); + return vmcb->control.tsc_offset + host_tsc; } static int svm_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) @@ -3086,7 +2994,7 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) switch (msr_info->index) { case MSR_IA32_TSC: { msr_info->data = svm->vmcb->control.tsc_offset + - svm_scale_tsc(vcpu, rdtsc()); + kvm_scale_tsc(vcpu, rdtsc()); break; } @@ -3362,6 +3270,7 @@ static int (*const svm_exit_handlers[])(struct vcpu_svm *svm) = { [SVM_EXIT_EXCP_BASE + PF_VECTOR] = pf_interception, [SVM_EXIT_EXCP_BASE + NM_VECTOR] = nm_interception, [SVM_EXIT_EXCP_BASE + MC_VECTOR] = mc_interception, + [SVM_EXIT_EXCP_BASE + AC_VECTOR] = ac_interception, [SVM_EXIT_INTR] = intr_interception, [SVM_EXIT_NMI] = nmi_interception, [SVM_EXIT_SMI] = nop_on_interception, @@ -3745,7 +3654,6 @@ static void enable_nmi_window(struct kvm_vcpu *vcpu) */ svm->nmi_singlestep = true; svm->vmcb->save.rflags |= (X86_EFLAGS_TF | X86_EFLAGS_RF); - update_db_bp_intercept(vcpu); } static int svm_set_tss_addr(struct kvm *kvm, unsigned int addr) @@ -4371,7 +4279,7 @@ static struct kvm_x86_ops svm_x86_ops = { .vcpu_load = svm_vcpu_load, .vcpu_put = svm_vcpu_put, - .update_db_bp_intercept = update_db_bp_intercept, + .update_bp_intercept = update_bp_intercept, .get_msr = svm_get_msr, .set_msr = svm_set_msr, .get_segment_base = svm_get_segment_base, @@ -4443,11 +4351,9 @@ static struct kvm_x86_ops svm_x86_ops = { .has_wbinvd_exit = svm_has_wbinvd_exit, - .set_tsc_khz = svm_set_tsc_khz, .read_tsc_offset = svm_read_tsc_offset, .write_tsc_offset = svm_write_tsc_offset, - .adjust_tsc_offset = svm_adjust_tsc_offset, - .compute_tsc_offset = svm_compute_tsc_offset, + .adjust_tsc_offset_guest = svm_adjust_tsc_offset_guest, .read_l1_tsc = svm_read_l1_tsc, .set_tdp_cr3 = set_tdp_cr3, diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 5eb56ed..87acc52 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -107,6 +107,8 @@ static u64 __read_mostly host_xss; static bool __read_mostly enable_pml = 1; module_param_named(pml, enable_pml, bool, S_IRUGO); +#define KVM_VMX_TSC_MULTIPLIER_MAX 0xffffffffffffffffULL + #define KVM_GUEST_CR0_MASK (X86_CR0_NW | X86_CR0_CD) #define KVM_VM_CR0_ALWAYS_ON_UNRESTRICTED_GUEST (X86_CR0_WP | X86_CR0_NE) #define KVM_VM_CR0_ALWAYS_ON \ @@ -1172,6 +1174,12 @@ static inline bool cpu_has_vmx_pml(void) return vmcs_config.cpu_based_2nd_exec_ctrl & SECONDARY_EXEC_ENABLE_PML; } +static inline bool cpu_has_vmx_tsc_scaling(void) +{ + return vmcs_config.cpu_based_2nd_exec_ctrl & + SECONDARY_EXEC_TSC_SCALING; +} + static inline bool report_flexpriority(void) { return flexpriority_enabled; @@ -1631,7 +1639,7 @@ static void update_exception_bitmap(struct kvm_vcpu *vcpu) u32 eb; eb = (1u << PF_VECTOR) | (1u << UD_VECTOR) | (1u << MC_VECTOR) | - (1u << NM_VECTOR) | (1u << DB_VECTOR); + (1u << NM_VECTOR) | (1u << DB_VECTOR) | (1u << AC_VECTOR); if ((vcpu->guest_debug & (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP)) == (KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP)) @@ -2053,6 +2061,12 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu, int cpu) rdmsrl(MSR_IA32_SYSENTER_ESP, sysenter_esp); vmcs_writel(HOST_IA32_SYSENTER_ESP, sysenter_esp); /* 22.2.3 */ + + /* Setup TSC multiplier */ + if (cpu_has_vmx_tsc_scaling()) + vmcs_write64(TSC_MULTIPLIER, + vcpu->arch.tsc_scaling_ratio); + vmx->loaded_vmcs->cpu = cpu; } @@ -2357,15 +2371,16 @@ static void setup_msrs(struct vcpu_vmx *vmx) /* * reads and returns guest's timestamp counter "register" - * guest_tsc = host_tsc + tsc_offset -- 21.3 + * guest_tsc = (host_tsc * tsc multiplier) >> 48 + tsc_offset + * -- Intel TSC Scaling for Virtualization White Paper, sec 1.3 */ -static u64 guest_read_tsc(void) +static u64 guest_read_tsc(struct kvm_vcpu *vcpu) { u64 host_tsc, tsc_offset; host_tsc = rdtsc(); tsc_offset = vmcs_read64(TSC_OFFSET); - return host_tsc + tsc_offset; + return kvm_scale_tsc(vcpu, host_tsc) + tsc_offset; } /* @@ -2382,22 +2397,6 @@ static u64 vmx_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc) return host_tsc + tsc_offset; } -/* - * Engage any workarounds for mis-matched TSC rates. Currently limited to - * software catchup for faster rates on slower CPUs. - */ -static void vmx_set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz, bool scale) -{ - if (!scale) - return; - - if (user_tsc_khz > tsc_khz) { - vcpu->arch.tsc_catchup = 1; - vcpu->arch.tsc_always_catchup = 1; - } else - WARN(1, "user requested TSC rate below hardware speed\n"); -} - static u64 vmx_read_tsc_offset(struct kvm_vcpu *vcpu) { return vmcs_read64(TSC_OFFSET); @@ -2429,7 +2428,7 @@ static void vmx_write_tsc_offset(struct kvm_vcpu *vcpu, u64 offset) } } -static void vmx_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment, bool host) +static void vmx_adjust_tsc_offset_guest(struct kvm_vcpu *vcpu, s64 adjustment) { u64 offset = vmcs_read64(TSC_OFFSET); @@ -2442,11 +2441,6 @@ static void vmx_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment, bool ho offset + adjustment); } -static u64 vmx_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc) -{ - return target_tsc - rdtsc(); -} - static bool guest_cpuid_has_vmx(struct kvm_vcpu *vcpu) { struct kvm_cpuid_entry2 *best = kvm_find_cpuid_entry(vcpu, 1, 0); @@ -2778,7 +2772,7 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) case MSR_EFER: return kvm_get_msr_common(vcpu, msr_info); case MSR_IA32_TSC: - msr_info->data = guest_read_tsc(); + msr_info->data = guest_read_tsc(vcpu); break; case MSR_IA32_SYSENTER_CS: msr_info->data = vmcs_read32(GUEST_SYSENTER_CS); @@ -3154,7 +3148,8 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf) SECONDARY_EXEC_SHADOW_VMCS | SECONDARY_EXEC_XSAVES | SECONDARY_EXEC_ENABLE_PML | - SECONDARY_EXEC_PCOMMIT; + SECONDARY_EXEC_PCOMMIT | + SECONDARY_EXEC_TSC_SCALING; if (adjust_vmx_controls(min2, opt2, MSR_IA32_VMX_PROCBASED_CTLS2, &_cpu_based_2nd_exec_control) < 0) @@ -5266,6 +5261,9 @@ static int handle_exception(struct kvm_vcpu *vcpu) return handle_rmode_exception(vcpu, ex_no, error_code); switch (ex_no) { + case AC_VECTOR: + kvm_queue_exception_e(vcpu, AC_VECTOR, error_code); + return 1; case DB_VECTOR: dr6 = vmcs_readl(EXIT_QUALIFICATION); if (!(vcpu->guest_debug & @@ -5908,7 +5906,7 @@ static int handle_ept_misconfig(struct kvm_vcpu *vcpu) return 1; } - ret = handle_mmio_page_fault_common(vcpu, gpa, true); + ret = handle_mmio_page_fault(vcpu, gpa, true); if (likely(ret == RET_MMIO_PF_EMULATE)) return x86_emulate_instruction(vcpu, gpa, 0, NULL, 0) == EMULATE_DONE; @@ -6199,6 +6197,12 @@ static __init int hardware_setup(void) if (!cpu_has_vmx_apicv()) enable_apicv = 0; + if (cpu_has_vmx_tsc_scaling()) { + kvm_has_tsc_control = true; + kvm_max_tsc_scaling_ratio = KVM_VMX_TSC_MULTIPLIER_MAX; + kvm_tsc_scaling_ratio_frac_bits = 48; + } + if (enable_apicv) kvm_x86_ops->update_cr8_intercept = NULL; else { @@ -8008,6 +8012,9 @@ static void dump_vmcs(void) vmcs_read32(IDT_VECTORING_INFO_FIELD), vmcs_read32(IDT_VECTORING_ERROR_CODE)); pr_err("TSC Offset = 0x%016lx\n", vmcs_readl(TSC_OFFSET)); + if (secondary_exec_control & SECONDARY_EXEC_TSC_SCALING) + pr_err("TSC Multiplier = 0x%016lx\n", + vmcs_readl(TSC_MULTIPLIER)); if (cpu_based_exec_ctrl & CPU_BASED_TPR_SHADOW) pr_err("TPR Threshold = 0x%02x\n", vmcs_read32(TPR_THRESHOLD)); if (pin_based_exec_ctrl & PIN_BASED_POSTED_INTR) @@ -10752,7 +10759,7 @@ static struct kvm_x86_ops vmx_x86_ops = { .vcpu_load = vmx_vcpu_load, .vcpu_put = vmx_vcpu_put, - .update_db_bp_intercept = update_exception_bitmap, + .update_bp_intercept = update_exception_bitmap, .get_msr = vmx_get_msr, .set_msr = vmx_set_msr, .get_segment_base = vmx_get_segment_base, @@ -10826,11 +10833,9 @@ static struct kvm_x86_ops vmx_x86_ops = { .has_wbinvd_exit = cpu_has_vmx_wbinvd_exit, - .set_tsc_khz = vmx_set_tsc_khz, .read_tsc_offset = vmx_read_tsc_offset, .write_tsc_offset = vmx_write_tsc_offset, - .adjust_tsc_offset = vmx_adjust_tsc_offset, - .compute_tsc_offset = vmx_compute_tsc_offset, + .adjust_tsc_offset_guest = vmx_adjust_tsc_offset_guest, .read_l1_tsc = vmx_read_l1_tsc, .set_tdp_cr3 = vmx_set_cr3, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 4a6eff1..00462bd 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -93,10 +93,10 @@ static void update_cr8_intercept(struct kvm_vcpu *vcpu); static void process_nmi(struct kvm_vcpu *vcpu); static void __kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags); -struct kvm_x86_ops *kvm_x86_ops; +struct kvm_x86_ops *kvm_x86_ops __read_mostly; EXPORT_SYMBOL_GPL(kvm_x86_ops); -static bool ignore_msrs = 0; +static bool __read_mostly ignore_msrs = 0; module_param(ignore_msrs, bool, S_IRUGO | S_IWUSR); unsigned int min_timer_period_us = 500; @@ -105,20 +105,25 @@ module_param(min_timer_period_us, uint, S_IRUGO | S_IWUSR); static bool __read_mostly kvmclock_periodic_sync = true; module_param(kvmclock_periodic_sync, bool, S_IRUGO); -bool kvm_has_tsc_control; +bool __read_mostly kvm_has_tsc_control; EXPORT_SYMBOL_GPL(kvm_has_tsc_control); -u32 kvm_max_guest_tsc_khz; +u32 __read_mostly kvm_max_guest_tsc_khz; EXPORT_SYMBOL_GPL(kvm_max_guest_tsc_khz); +u8 __read_mostly kvm_tsc_scaling_ratio_frac_bits; +EXPORT_SYMBOL_GPL(kvm_tsc_scaling_ratio_frac_bits); +u64 __read_mostly kvm_max_tsc_scaling_ratio; +EXPORT_SYMBOL_GPL(kvm_max_tsc_scaling_ratio); +static u64 __read_mostly kvm_default_tsc_scaling_ratio; /* tsc tolerance in parts per million - default to 1/2 of the NTP threshold */ -static u32 tsc_tolerance_ppm = 250; +static u32 __read_mostly tsc_tolerance_ppm = 250; module_param(tsc_tolerance_ppm, uint, S_IRUGO | S_IWUSR); /* lapic timer advance (tscdeadline mode only) in nanoseconds */ -unsigned int lapic_timer_advance_ns = 0; +unsigned int __read_mostly lapic_timer_advance_ns = 0; module_param(lapic_timer_advance_ns, uint, S_IRUGO | S_IWUSR); -static bool backwards_tsc_observed = false; +static bool __read_mostly backwards_tsc_observed = false; #define KVM_NR_SHARED_MSRS 16 @@ -1249,14 +1254,53 @@ static u32 adjust_tsc_khz(u32 khz, s32 ppm) return v; } -static void kvm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 this_tsc_khz) +static int set_tsc_khz(struct kvm_vcpu *vcpu, u32 user_tsc_khz, bool scale) +{ + u64 ratio; + + /* Guest TSC same frequency as host TSC? */ + if (!scale) { + vcpu->arch.tsc_scaling_ratio = kvm_default_tsc_scaling_ratio; + return 0; + } + + /* TSC scaling supported? */ + if (!kvm_has_tsc_control) { + if (user_tsc_khz > tsc_khz) { + vcpu->arch.tsc_catchup = 1; + vcpu->arch.tsc_always_catchup = 1; + return 0; + } else { + WARN(1, "user requested TSC rate below hardware speed\n"); + return -1; + } + } + + /* TSC scaling required - calculate ratio */ + ratio = mul_u64_u32_div(1ULL << kvm_tsc_scaling_ratio_frac_bits, + user_tsc_khz, tsc_khz); + + if (ratio == 0 || ratio >= kvm_max_tsc_scaling_ratio) { + WARN_ONCE(1, "Invalid TSC scaling ratio - virtual-tsc-khz=%u\n", + user_tsc_khz); + return -1; + } + + vcpu->arch.tsc_scaling_ratio = ratio; + return 0; +} + +static int kvm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 this_tsc_khz) { u32 thresh_lo, thresh_hi; int use_scaling = 0; /* tsc_khz can be zero if TSC calibration fails */ - if (this_tsc_khz == 0) - return; + if (this_tsc_khz == 0) { + /* set tsc_scaling_ratio to a safe value */ + vcpu->arch.tsc_scaling_ratio = kvm_default_tsc_scaling_ratio; + return -1; + } /* Compute a scale to convert nanoseconds in TSC cycles */ kvm_get_time_scale(this_tsc_khz, NSEC_PER_SEC / 1000, @@ -1276,7 +1320,7 @@ static void kvm_set_tsc_khz(struct kvm_vcpu *vcpu, u32 this_tsc_khz) pr_debug("kvm: requested TSC rate %u falls outside tolerance [%u,%u]\n", this_tsc_khz, thresh_lo, thresh_hi); use_scaling = 1; } - kvm_x86_ops->set_tsc_khz(vcpu, this_tsc_khz, use_scaling); + return set_tsc_khz(vcpu, this_tsc_khz, use_scaling); } static u64 compute_guest_tsc(struct kvm_vcpu *vcpu, s64 kernel_ns) @@ -1322,6 +1366,48 @@ static void update_ia32_tsc_adjust_msr(struct kvm_vcpu *vcpu, s64 offset) vcpu->arch.ia32_tsc_adjust_msr += offset - curr_offset; } +/* + * Multiply tsc by a fixed point number represented by ratio. + * + * The most significant 64-N bits (mult) of ratio represent the + * integral part of the fixed point number; the remaining N bits + * (frac) represent the fractional part, ie. ratio represents a fixed + * point number (mult + frac * 2^(-N)). + * + * N equals to kvm_tsc_scaling_ratio_frac_bits. + */ +static inline u64 __scale_tsc(u64 ratio, u64 tsc) +{ + return mul_u64_u64_shr(tsc, ratio, kvm_tsc_scaling_ratio_frac_bits); +} + +u64 kvm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc) +{ + u64 _tsc = tsc; + u64 ratio = vcpu->arch.tsc_scaling_ratio; + + if (ratio != kvm_default_tsc_scaling_ratio) + _tsc = __scale_tsc(ratio, tsc); + + return _tsc; +} +EXPORT_SYMBOL_GPL(kvm_scale_tsc); + +static u64 kvm_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc) +{ + u64 tsc; + + tsc = kvm_scale_tsc(vcpu, rdtsc()); + + return target_tsc - tsc; +} + +u64 kvm_read_l1_tsc(struct kvm_vcpu *vcpu, u64 host_tsc) +{ + return kvm_x86_ops->read_l1_tsc(vcpu, kvm_scale_tsc(vcpu, host_tsc)); +} +EXPORT_SYMBOL_GPL(kvm_read_l1_tsc); + void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr) { struct kvm *kvm = vcpu->kvm; @@ -1333,7 +1419,7 @@ void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr) u64 data = msr->data; raw_spin_lock_irqsave(&kvm->arch.tsc_write_lock, flags); - offset = kvm_x86_ops->compute_tsc_offset(vcpu, data); + offset = kvm_compute_tsc_offset(vcpu, data); ns = get_kernel_ns(); elapsed = ns - kvm->arch.last_tsc_nsec; @@ -1390,7 +1476,7 @@ void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr) } else { u64 delta = nsec_to_cycles(vcpu, elapsed); data += delta; - offset = kvm_x86_ops->compute_tsc_offset(vcpu, data); + offset = kvm_compute_tsc_offset(vcpu, data); pr_debug("kvm: adjusted tsc offset by %llu\n", delta); } matched = true; @@ -1447,6 +1533,20 @@ void kvm_write_tsc(struct kvm_vcpu *vcpu, struct msr_data *msr) EXPORT_SYMBOL_GPL(kvm_write_tsc); +static inline void adjust_tsc_offset_guest(struct kvm_vcpu *vcpu, + s64 adjustment) +{ + kvm_x86_ops->adjust_tsc_offset_guest(vcpu, adjustment); +} + +static inline void adjust_tsc_offset_host(struct kvm_vcpu *vcpu, s64 adjustment) +{ + if (vcpu->arch.tsc_scaling_ratio != kvm_default_tsc_scaling_ratio) + WARN_ON(adjustment < 0); + adjustment = kvm_scale_tsc(vcpu, (u64) adjustment); + kvm_x86_ops->adjust_tsc_offset_guest(vcpu, adjustment); +} + #ifdef CONFIG_X86_64 static cycle_t read_tsc(void) @@ -1608,7 +1708,7 @@ static void kvm_gen_update_masterclock(struct kvm *kvm) static int kvm_guest_time_update(struct kvm_vcpu *v) { - unsigned long flags, this_tsc_khz; + unsigned long flags, this_tsc_khz, tgt_tsc_khz; struct kvm_vcpu_arch *vcpu = &v->arch; struct kvm_arch *ka = &v->kvm->arch; s64 kernel_ns; @@ -1645,7 +1745,7 @@ static int kvm_guest_time_update(struct kvm_vcpu *v) kernel_ns = get_kernel_ns(); } - tsc_timestamp = kvm_x86_ops->read_l1_tsc(v, host_tsc); + tsc_timestamp = kvm_read_l1_tsc(v, host_tsc); /* * We may have to catch up the TSC to match elapsed wall clock @@ -1671,7 +1771,9 @@ static int kvm_guest_time_update(struct kvm_vcpu *v) return 0; if (unlikely(vcpu->hw_tsc_khz != this_tsc_khz)) { - kvm_get_time_scale(NSEC_PER_SEC / 1000, this_tsc_khz, + tgt_tsc_khz = kvm_has_tsc_control ? + vcpu->virtual_tsc_khz : this_tsc_khz; + kvm_get_time_scale(NSEC_PER_SEC / 1000, tgt_tsc_khz, &vcpu->hv_clock.tsc_shift, &vcpu->hv_clock.tsc_to_system_mul); vcpu->hw_tsc_khz = this_tsc_khz; @@ -2617,7 +2719,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) if (tsc_delta < 0) mark_tsc_unstable("KVM discovered backwards TSC"); if (check_tsc_unstable()) { - u64 offset = kvm_x86_ops->compute_tsc_offset(vcpu, + u64 offset = kvm_compute_tsc_offset(vcpu, vcpu->arch.last_guest_tsc); kvm_x86_ops->write_tsc_offset(vcpu, offset); vcpu->arch.tsc_catchup = 1; @@ -3319,9 +3421,9 @@ long kvm_arch_vcpu_ioctl(struct file *filp, if (user_tsc_khz == 0) user_tsc_khz = tsc_khz; - kvm_set_tsc_khz(vcpu, user_tsc_khz); + if (!kvm_set_tsc_khz(vcpu, user_tsc_khz)) + r = 0; - r = 0; goto out; } case KVM_GET_TSC_KHZ: { @@ -6452,8 +6554,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) if (hw_breakpoint_active()) hw_breakpoint_restore(); - vcpu->arch.last_guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, - rdtsc()); + vcpu->arch.last_guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc()); vcpu->mode = OUTSIDE_GUEST_MODE; smp_wmb(); @@ -7015,7 +7116,7 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, */ kvm_set_rflags(vcpu, rflags); - kvm_x86_ops->update_db_bp_intercept(vcpu); + kvm_x86_ops->update_bp_intercept(vcpu); r = 0; @@ -7364,6 +7465,20 @@ int kvm_arch_hardware_setup(void) if (r != 0) return r; + if (kvm_has_tsc_control) { + /* + * Make sure the user can only configure tsc_khz values that + * fit into a signed integer. + * A min value is not calculated needed because it will always + * be 1 on all machines. + */ + u64 max = min(0x7fffffffULL, + __scale_tsc(kvm_max_tsc_scaling_ratio, tsc_khz)); + kvm_max_guest_tsc_khz = max; + + kvm_default_tsc_scaling_ratio = 1ULL << kvm_tsc_scaling_ratio_frac_bits; + } + kvm_init_msr_list(); return 0; } |