> > > > On 19/10/21 09:23, Vitaly Kuznetsov wrote: > > >> > > >> -static void pv_eoi_clr_pending(struct kvm_vcpu *vcpu) > > >> +static void pv_eoi_clr_pending(struct kvm_vcpu *vcpu, bool > > >> +pending) > > > Nitpick (and probably a matter of personal taste): > > > pv_eoi_clr_pending() has only one user and the change doesn't make > > > its interface much nicer, I'd suggest we just inline in instead. (we > > > can probably do the same to > > > pv_eoi_get_pending()/pv_eoi_set_pending() too). > > > > Alternatively, merge pv_eoi_get_pending and pv_eoi_clr_pending into a > > single function pv_eoi_test_and_clear_pending, which returns the value > > of the pending bit. > > > > So the caller can do essentially: > > > > - pending = pv_eoi_get_pending(vcpu); > > - pv_eoi_clr_pending(vcpu); > > - if (pending) > > + if (pv_eoi_test_and_clear_pending(vcpu)) > > return; > > > > > > It is better to implement pv_eoi_test_and_clear_pending(), and it can fix the > race that Vitaly suggested > > And I will write a new function kvm_test_and_clear_bit_guest_cached, to be > called in pv_eoi_test_and_clear_pending > > Bool kvm_test_and_clear_bit_guest_cached（struct kvm_vcpu *vcpu， struct > gfn_to_hva_cache * ghc， long nr） > gfn_to_hva_cache has hva(user space address), but no hpa, and test_and_clear() can not be used to user space address. So kvm_test_and_clear_bit_guest_cached seems not work -Li > -Li > > > Paolo
