From 127770ac0d043435375ab86434f31a93efa88215 Mon Sep 17 00:00:00 2001 From: Aaron Lewis Date: Mon, 14 Feb 2022 21:29:51 +0000 Subject: KVM: x86: Add KVM_CAP_ENABLE_CAP to x86 Follow the precedent set by other architectures that support the VCPU ioctl, KVM_ENABLE_CAP, and advertise the VM extension, KVM_CAP_ENABLE_CAP. This way, userspace can ensure that KVM_ENABLE_CAP is available on a vcpu before using it. Fixes: 5c919412fe61 ("kvm/x86: Hyper-V synthetic interrupt controller") Signed-off-by: Aaron Lewis Message-Id: <20220214212950.1776943-1-aaronlewis@google.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/kvm/x86.c') diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 641044db415d..b8bd8da32045 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4233,6 +4233,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_EXIT_ON_EMULATION_FAILURE: case KVM_CAP_VCPU_ATTRIBUTES: case KVM_CAP_SYS_ATTRIBUTES: + case KVM_CAP_ENABLE_CAP: r = 1; break; case KVM_CAP_EXIT_HYPERCALL: -- cgit v1.2.3 From 3a55f729240a686aa8af00af436306c0cd532522 Mon Sep 17 00:00:00 2001 From: Anton Romanov Date: Wed, 16 Feb 2022 18:26:54 +0000 Subject: kvm: x86: Disable KVM_HC_CLOCK_PAIRING if tsc is in always catchup mode If vcpu has tsc_always_catchup set each request updates pvclock data. KVM_HC_CLOCK_PAIRING consumers such as ptp_kvm_x86 rely on tsc read on host's side and do hypercall inside pvclock_read_retry loop leading to infinite loop in such situation. v3: Removed warn Changed return code to KVM_EFAULT v2: Added warn Signed-off-by: Anton Romanov Message-Id: <20220216182653.506850-1-romanton@google.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'arch/x86/kvm/x86.c') diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b8bd8da32045..3471efe47e5f 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -8943,6 +8943,13 @@ static int kvm_pv_clock_pairing(struct kvm_vcpu *vcpu, gpa_t paddr, if (clock_type != KVM_CLOCK_PAIRING_WALLCLOCK) return -KVM_EOPNOTSUPP; + /* + * When tsc is in permanent catchup mode guests won't be able to use + * pvclock_read_retry loop to get consistent view of pvclock + */ + if (vcpu->arch.tsc_always_catchup) + return -KVM_EOPNOTSUPP; + if (!kvm_get_walltime_and_clockread(&ts, &cycle)) return -KVM_EOPNOTSUPP; -- cgit v1.2.3 From 988896bb61827345c6d074dd5f2af1b7b008193f Mon Sep 17 00:00:00 2001 From: Leonardo Bras Date: Thu, 17 Feb 2022 02:30:30 -0300 Subject: x86/kvm/fpu: Remove kvm_vcpu_arch.guest_supported_xcr0 kvm_vcpu_arch currently contains the guest supported features in both guest_supported_xcr0 and guest_fpu.fpstate->user_xfeatures field. Currently both fields are set to the same value in kvm_vcpu_after_set_cpuid() and are not changed anywhere else after that. Since it's not good to keep duplicated data, remove guest_supported_xcr0. To keep the code more readable, introduce kvm_guest_supported_xcr() and kvm_guest_supported_xfd() to replace the previous usages of guest_supported_xcr0. Signed-off-by: Leonardo Bras Message-Id: <20220217053028.96432-3-leobras@redhat.com> Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 1 - arch/x86/kvm/cpuid.c | 5 +++-- arch/x86/kvm/x86.c | 18 +++++++++++++----- 3 files changed, 16 insertions(+), 8 deletions(-) (limited to 'arch/x86/kvm/x86.c') diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 6dcccb304775..ec9830d2aabf 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -703,7 +703,6 @@ struct kvm_vcpu_arch { struct fpu_guest guest_fpu; u64 xcr0; - u64 guest_supported_xcr0; struct kvm_pio_request pio; void *pio_data; diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 71125291c578..b8f8d268d058 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -282,6 +282,7 @@ static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) { struct kvm_lapic *apic = vcpu->arch.apic; struct kvm_cpuid_entry2 *best; + u64 guest_supported_xcr0; best = kvm_find_cpuid_entry(vcpu, 1, 0); if (best && apic) { @@ -293,10 +294,10 @@ static void kvm_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) kvm_apic_set_version(vcpu); } - vcpu->arch.guest_supported_xcr0 = + guest_supported_xcr0 = cpuid_get_supported_xcr0(vcpu->arch.cpuid_entries, vcpu->arch.cpuid_nent); - vcpu->arch.guest_fpu.fpstate->user_xfeatures = vcpu->arch.guest_supported_xcr0; + vcpu->arch.guest_fpu.fpstate->user_xfeatures = guest_supported_xcr0; kvm_update_pv_runtime(vcpu); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 3471efe47e5f..20ad6fe391bf 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -984,6 +984,16 @@ void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu) } EXPORT_SYMBOL_GPL(kvm_load_host_xsave_state); +static inline u64 kvm_guest_supported_xcr0(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.guest_fpu.fpstate->user_xfeatures; +} + +static inline u64 kvm_guest_supported_xfd(struct kvm_vcpu *vcpu) +{ + return kvm_guest_supported_xcr0(vcpu) & XFEATURE_MASK_USER_DYNAMIC; +} + static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) { u64 xcr0 = xcr; @@ -1003,7 +1013,7 @@ static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) * saving. However, xcr0 bit 0 is always set, even if the * emulated CPU does not support XSAVE (see kvm_vcpu_reset()). */ - valid_bits = vcpu->arch.guest_supported_xcr0 | XFEATURE_MASK_FP; + valid_bits = kvm_guest_supported_xcr0(vcpu) | XFEATURE_MASK_FP; if (xcr0 & ~valid_bits) return 1; @@ -3706,8 +3716,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) !guest_cpuid_has(vcpu, X86_FEATURE_XFD)) return 1; - if (data & ~(XFEATURE_MASK_USER_DYNAMIC & - vcpu->arch.guest_supported_xcr0)) + if (data & ~kvm_guest_supported_xfd(vcpu)) return 1; fpu_update_guest_xfd(&vcpu->arch.guest_fpu, data); @@ -3717,8 +3726,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) !guest_cpuid_has(vcpu, X86_FEATURE_XFD)) return 1; - if (data & ~(XFEATURE_MASK_USER_DYNAMIC & - vcpu->arch.guest_supported_xcr0)) + if (data & ~kvm_guest_supported_xfd(vcpu)) return 1; vcpu->arch.guest_fpu.xfd_err = data; -- cgit v1.2.3 From ba1f77c546966c12d86220d078e5838dcaeab348 Mon Sep 17 00:00:00 2001 From: Leonardo Bras Date: Fri, 18 Feb 2022 00:41:00 -0300 Subject: x86/kvm: Fix compilation warning in non-x86_64 builds On non-x86_64 builds, helpers gtod_is_based_on_tsc() and kvm_guest_supported_xfd() are defined but never used. Because these are static inline but are in a .c file, some compilers do warn for them with -Wunused-function, which becomes an error if -Werror is present. Add #ifdef so they are only defined in x86_64 builds. Reported-by: kernel test robot Signed-off-by: Leonardo Bras Message-Id: <20220218034100.115702-1-leobras@redhat.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'arch/x86/kvm/x86.c') diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 20ad6fe391bf..82a9dcd8c67f 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -989,10 +989,12 @@ static inline u64 kvm_guest_supported_xcr0(struct kvm_vcpu *vcpu) return vcpu->arch.guest_fpu.fpstate->user_xfeatures; } +#ifdef CONFIG_X86_64 static inline u64 kvm_guest_supported_xfd(struct kvm_vcpu *vcpu) { return kvm_guest_supported_xcr0(vcpu) & XFEATURE_MASK_USER_DYNAMIC; } +#endif static int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) { @@ -2361,10 +2363,12 @@ static u64 compute_guest_tsc(struct kvm_vcpu *vcpu, s64 kernel_ns) return tsc; } +#ifdef CONFIG_X86_64 static inline int gtod_is_based_on_tsc(int mode) { return mode == VDSO_CLOCKMODE_TSC || mode == VDSO_CLOCKMODE_HVCLOCK; } +#endif static void kvm_track_tsc_matching(struct kvm_vcpu *vcpu) { -- cgit v1.2.3