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charset="us-ascii" On Mon, Apr 22, 2024, Xiaoyao Li wrote: > On 4/19/2024 4:59 PM, Paolo Bonzini wrote: > > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > > index 10e90788b263..a045b23964c0 100644 > > --- a/arch/x86/kvm/mmu/mmu.c > > +++ b/arch/x86/kvm/mmu/mmu.c > > @@ -4647,6 +4647,78 @@ int kvm_tdp_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) > > return direct_page_fault(vcpu, fault); > > } > > +static int kvm_tdp_map_page(struct kvm_vcpu *vcpu, gpa_t gpa, u64 error_code, > > + u8 *level) Align parameters: static int kvm_tdp_map_page(struct kvm_vcpu *vcpu, gpa_t gpa, u64 error_code, u8 *level) > > +{ > > + int r; > > + > > + /* Restrict to TDP page fault. */ This is fairly obvious from the code, what might not be obvious is _why_. I'm also ok dropping the comment entirely, but it's easy enough to provide a hint to the reader. > > + if (vcpu->arch.mmu->page_fault != kvm_tdp_page_fault) > > + return -EOPNOTSUPP; > > + > > +retry: > > + r = __kvm_mmu_do_page_fault(vcpu, gpa, error_code, true, NULL, level); > > + if (r < 0) > > + return r; > > + > > + switch (r) { > > + case RET_PF_RETRY: > > + if (signal_pending(current)) > > + return -EINTR; > > + cond_resched(); > > + goto retry; Rather than a goto+retry from inside a switch statement, what about: int r; /* * Pre-faulting a GPA is supported only non-nested TDP, as indirect * MMUs map either GVAs or L2 GPAs, not L1 GPAs. */ if (vcpu->arch.mmu->page_fault != kvm_tdp_page_fault) return -EOPNOTSUPP; do { if (signal_pending(current)) return -EINTR; cond_resched(); r = kvm_mmu_do_page_fault(vcpu, gpa, error_code, true, NULL, level); } while (r == RET_PF_RETRY); switch (r) { case RET_PF_FIXED: case RET_PF_SPURIOUS: break; case RET_PF_EMULATE: return -ENOENT; case RET_PF_CONTINUE: case RET_PF_INVALID: case RET_PF_RETRY: default: WARN_ON_ONCE(r >= 0); return -EIO; } return 0;