Wrap kvm_guest_time_update()'s entire use_master_clock block in #ifdef CONFIG_X86_64 and providing a hardcoded-to-false variable for the 32-bit path, as use_master_clock is never true on 32-bit (host_tsc_clocksource is only set under CONFIG_X86_64) Keep the local "ka" variable outside of the 64-bit-only code as it's also used for Xen code, but tag it as potentially unused since it's not used on 32-bit kernels without Xen emulation. For all intents and purposes, no functional change intended. Signed-off-by: Sean Christopherson --- arch/x86/kvm/x86.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 63702be799cc..070a12535788 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1796,22 +1796,21 @@ static void kvm_setup_guest_pvclock(struct pvclock_vcpu_time_info *ref_hv_clock, int kvm_guest_time_update(struct kvm_vcpu *v) { + struct kvm_arch *ka __maybe_unused = &v->kvm->arch; struct pvclock_vcpu_time_info hv_clock = {}; u64 tgt_tsc_hz; - unsigned seq; struct kvm_vcpu_arch *vcpu = &v->arch; - struct kvm_arch *ka = &v->kvm->arch; s64 kernel_ns; u64 tsc_timestamp, host_tsc; + + /* + * If the host uses TSC clock, then passthrough TSC as stable + * to the guest. + */ +#ifdef CONFIG_X86_64 bool use_master_clock; + unsigned int seq; - kernel_ns = 0; - host_tsc = 0; - - /* - * If the host uses TSC clock, then passthrough TSC as stable - * to the guest. - */ do { seq = read_seqcount_begin(&ka->pvclock_sc); use_master_clock = ka->use_master_clock; @@ -1820,7 +1819,9 @@ int kvm_guest_time_update(struct kvm_vcpu *v) kernel_ns = ka->master_kernel_ns; } } while (read_seqcount_retry(&ka->pvclock_sc, seq)); - +#else + const bool use_master_clock = false; +#endif /* * Ensure reading the TSC+frequency pair is done on the same CPU. When * NOT using the master clock, the TSC frequency may vary between CPUs. -- 2.55.0.571.g244d577d93-goog