| Message ID | 20210504171734.1434054-14-seanjc@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: x86: RDPID/RDTSCP fixes and uret MSR cleanups | expand |
On Tue, 2021-05-04 at 10:17 -0700, Sean Christopherson wrote: > Now that SVM and VMX both probe MSRs before "defining" user return slots > for them, consolidate the code for probe+define into common x86 and > eliminate the odd behavior of having the vendor code define the slot for > a given MSR. > > Signed-off-by: Sean Christopherson <seanjc@google.com> > --- > arch/x86/include/asm/kvm_host.h | 3 +-- > arch/x86/kvm/svm/svm.c | 5 +---- > arch/x86/kvm/vmx/vmx.c | 19 ++++--------------- > arch/x86/kvm/x86.c | 19 +++++++++++-------- > 4 files changed, 17 insertions(+), 29 deletions(-) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 10663610f105..a4b912f7e427 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -1778,9 +1778,8 @@ int kvm_pv_send_ipi(struct kvm *kvm, unsigned long ipi_bitmap_low, > unsigned long ipi_bitmap_high, u32 min, > unsigned long icr, int op_64_bit); > > -void kvm_define_user_return_msr(unsigned index, u32 msr); > +int kvm_add_user_return_msr(u32 msr); > int kvm_find_user_return_msr(u32 msr); > -int kvm_probe_user_return_msr(u32 msr); > int kvm_set_user_return_msr(unsigned index, u64 val, u64 mask); > > u64 kvm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc); > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c > index 231b9650d864..de921935e8de 100644 > --- a/arch/x86/kvm/svm/svm.c > +++ b/arch/x86/kvm/svm/svm.c > @@ -959,10 +959,7 @@ static __init int svm_hardware_setup(void) > kvm_tsc_scaling_ratio_frac_bits = 32; > } > > - if (!kvm_probe_user_return_msr(MSR_TSC_AUX)) { > - tsc_aux_uret_slot = 0; > - kvm_define_user_return_msr(tsc_aux_uret_slot, MSR_TSC_AUX); > - } > + tsc_aux_uret_slot = kvm_add_user_return_msr(MSR_TSC_AUX); > > /* Check for pause filtering support */ > if (!boot_cpu_has(X86_FEATURE_PAUSEFILTER)) { > diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c > index 7a53568b34fc..26f82f302391 100644 > --- a/arch/x86/kvm/vmx/vmx.c > +++ b/arch/x86/kvm/vmx/vmx.c > @@ -454,9 +454,6 @@ static inline void vmx_segment_cache_clear(struct vcpu_vmx *vmx) > > static unsigned long host_idt_base; > > -/* Number of user return MSRs that are actually supported in hardware. */ > -static int vmx_nr_uret_msrs; > - > #if IS_ENABLED(CONFIG_HYPERV) > static bool __read_mostly enlightened_vmcs = true; > module_param(enlightened_vmcs, bool, 0444); > @@ -1218,7 +1215,7 @@ void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu) > */ > if (!vmx->guest_uret_msrs_loaded) { > vmx->guest_uret_msrs_loaded = true; > - for (i = 0; i < vmx_nr_uret_msrs; ++i) { > + for (i = 0; i < kvm_nr_uret_msrs; ++i) { > if (!vmx->guest_uret_msrs[i].load_into_hardware) > continue; > > @@ -6921,7 +6918,7 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu) > goto free_vpid; > } > > - for (i = 0; i < vmx_nr_uret_msrs; ++i) { > + for (i = 0; i < kvm_nr_uret_msrs; ++i) { > vmx->guest_uret_msrs[i].data = 0; > vmx->guest_uret_msrs[i].mask = -1ull; > } > @@ -7810,20 +7807,12 @@ static __init void vmx_setup_user_return_msrs(void) > MSR_EFER, MSR_TSC_AUX, MSR_STAR, > MSR_IA32_TSX_CTRL, > }; > - u32 msr; > int i; > > BUILD_BUG_ON(ARRAY_SIZE(vmx_uret_msrs_list) != MAX_NR_USER_RETURN_MSRS); > > - for (i = 0; i < ARRAY_SIZE(vmx_uret_msrs_list); ++i) { > - msr = vmx_uret_msrs_list[i]; > - > - if (kvm_probe_user_return_msr(msr)) > - continue; > - > - kvm_define_user_return_msr(vmx_nr_uret_msrs, msr); > - vmx_nr_uret_msrs++; > - } > + for (i = 0; i < ARRAY_SIZE(vmx_uret_msrs_list); ++i) > + kvm_add_user_return_msr(vmx_uret_msrs_list[i]); > } > > static __init int hardware_setup(void) > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 2fd46e917666..adca491d3b4b 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -336,7 +336,7 @@ static void kvm_on_user_return(struct user_return_notifier *urn) > } > } > > -int kvm_probe_user_return_msr(u32 msr) > +static int kvm_probe_user_return_msr(u32 msr) > { > u64 val; > int ret; > @@ -350,16 +350,18 @@ int kvm_probe_user_return_msr(u32 msr) > preempt_enable(); > return ret; > } > -EXPORT_SYMBOL_GPL(kvm_probe_user_return_msr); > > -void kvm_define_user_return_msr(unsigned slot, u32 msr) > +int kvm_add_user_return_msr(u32 msr) > { > - BUG_ON(slot >= KVM_MAX_NR_USER_RETURN_MSRS); > - kvm_uret_msrs_list[slot] = msr; > - if (slot >= kvm_nr_uret_msrs) > - kvm_nr_uret_msrs = slot + 1; > + BUG_ON(kvm_nr_uret_msrs >= KVM_MAX_NR_USER_RETURN_MSRS); > + > + if (kvm_probe_user_return_msr(msr)) > + return -1; > + > + kvm_uret_msrs_list[kvm_nr_uret_msrs] = msr; > + return kvm_nr_uret_msrs++; > } > -EXPORT_SYMBOL_GPL(kvm_define_user_return_msr); > +EXPORT_SYMBOL_GPL(kvm_add_user_return_msr); > > int kvm_find_user_return_msr(u32 msr) > { > @@ -8169,6 +8171,7 @@ int kvm_arch_init(void *opaque) > printk(KERN_ERR "kvm: failed to allocate percpu kvm_user_return_msrs\n"); > goto out_free_x86_emulator_cache; > } > + kvm_nr_uret_msrs = 0; > > r = kvm_mmu_module_init(); > if (r) Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Best regards, Maxim Levitsky
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 10663610f105..a4b912f7e427 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1778,9 +1778,8 @@ int kvm_pv_send_ipi(struct kvm *kvm, unsigned long ipi_bitmap_low, unsigned long ipi_bitmap_high, u32 min, unsigned long icr, int op_64_bit); -void kvm_define_user_return_msr(unsigned index, u32 msr); +int kvm_add_user_return_msr(u32 msr); int kvm_find_user_return_msr(u32 msr); -int kvm_probe_user_return_msr(u32 msr); int kvm_set_user_return_msr(unsigned index, u64 val, u64 mask); u64 kvm_scale_tsc(struct kvm_vcpu *vcpu, u64 tsc); diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 231b9650d864..de921935e8de 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -959,10 +959,7 @@ static __init int svm_hardware_setup(void) kvm_tsc_scaling_ratio_frac_bits = 32; } - if (!kvm_probe_user_return_msr(MSR_TSC_AUX)) { - tsc_aux_uret_slot = 0; - kvm_define_user_return_msr(tsc_aux_uret_slot, MSR_TSC_AUX); - } + tsc_aux_uret_slot = kvm_add_user_return_msr(MSR_TSC_AUX); /* Check for pause filtering support */ if (!boot_cpu_has(X86_FEATURE_PAUSEFILTER)) { diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 7a53568b34fc..26f82f302391 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -454,9 +454,6 @@ static inline void vmx_segment_cache_clear(struct vcpu_vmx *vmx) static unsigned long host_idt_base; -/* Number of user return MSRs that are actually supported in hardware. */ -static int vmx_nr_uret_msrs; - #if IS_ENABLED(CONFIG_HYPERV) static bool __read_mostly enlightened_vmcs = true; module_param(enlightened_vmcs, bool, 0444); @@ -1218,7 +1215,7 @@ void vmx_prepare_switch_to_guest(struct kvm_vcpu *vcpu) */ if (!vmx->guest_uret_msrs_loaded) { vmx->guest_uret_msrs_loaded = true; - for (i = 0; i < vmx_nr_uret_msrs; ++i) { + for (i = 0; i < kvm_nr_uret_msrs; ++i) { if (!vmx->guest_uret_msrs[i].load_into_hardware) continue; @@ -6921,7 +6918,7 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu) goto free_vpid; } - for (i = 0; i < vmx_nr_uret_msrs; ++i) { + for (i = 0; i < kvm_nr_uret_msrs; ++i) { vmx->guest_uret_msrs[i].data = 0; vmx->guest_uret_msrs[i].mask = -1ull; } @@ -7810,20 +7807,12 @@ static __init void vmx_setup_user_return_msrs(void) MSR_EFER, MSR_TSC_AUX, MSR_STAR, MSR_IA32_TSX_CTRL, }; - u32 msr; int i; BUILD_BUG_ON(ARRAY_SIZE(vmx_uret_msrs_list) != MAX_NR_USER_RETURN_MSRS); - for (i = 0; i < ARRAY_SIZE(vmx_uret_msrs_list); ++i) { - msr = vmx_uret_msrs_list[i]; - - if (kvm_probe_user_return_msr(msr)) - continue; - - kvm_define_user_return_msr(vmx_nr_uret_msrs, msr); - vmx_nr_uret_msrs++; - } + for (i = 0; i < ARRAY_SIZE(vmx_uret_msrs_list); ++i) + kvm_add_user_return_msr(vmx_uret_msrs_list[i]); } static __init int hardware_setup(void) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2fd46e917666..adca491d3b4b 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -336,7 +336,7 @@ static void kvm_on_user_return(struct user_return_notifier *urn) } } -int kvm_probe_user_return_msr(u32 msr) +static int kvm_probe_user_return_msr(u32 msr) { u64 val; int ret; @@ -350,16 +350,18 @@ int kvm_probe_user_return_msr(u32 msr) preempt_enable(); return ret; } -EXPORT_SYMBOL_GPL(kvm_probe_user_return_msr); -void kvm_define_user_return_msr(unsigned slot, u32 msr) +int kvm_add_user_return_msr(u32 msr) { - BUG_ON(slot >= KVM_MAX_NR_USER_RETURN_MSRS); - kvm_uret_msrs_list[slot] = msr; - if (slot >= kvm_nr_uret_msrs) - kvm_nr_uret_msrs = slot + 1; + BUG_ON(kvm_nr_uret_msrs >= KVM_MAX_NR_USER_RETURN_MSRS); + + if (kvm_probe_user_return_msr(msr)) + return -1; + + kvm_uret_msrs_list[kvm_nr_uret_msrs] = msr; + return kvm_nr_uret_msrs++; } -EXPORT_SYMBOL_GPL(kvm_define_user_return_msr); +EXPORT_SYMBOL_GPL(kvm_add_user_return_msr); int kvm_find_user_return_msr(u32 msr) { @@ -8169,6 +8171,7 @@ int kvm_arch_init(void *opaque) printk(KERN_ERR "kvm: failed to allocate percpu kvm_user_return_msrs\n"); goto out_free_x86_emulator_cache; } + kvm_nr_uret_msrs = 0; r = kvm_mmu_module_init(); if (r)
Now that SVM and VMX both probe MSRs before "defining" user return slots for them, consolidate the code for probe+define into common x86 and eliminate the odd behavior of having the vendor code define the slot for a given MSR. Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/x86/include/asm/kvm_host.h | 3 +-- arch/x86/kvm/svm/svm.c | 5 +---- arch/x86/kvm/vmx/vmx.c | 19 ++++--------------- arch/x86/kvm/x86.c | 19 +++++++++++-------- 4 files changed, 17 insertions(+), 29 deletions(-)