On Thu, Mar 16, 2023, Shameerali Kolothum Thodi wrote: > > From: Sean Christopherson [mailto:seanjc@xxxxxxxxxx] > > On Thu, Mar 16, 2023, Shameerali Kolothum Thodi wrote: > > > > From: Sean Christopherson [mailto:seanjc@xxxxxxxxxx] On Thu, Mar 16, > > > > 2023, Shameer Kolothum wrote: > > > > > The stub for !CONFIG_HAVE_KVM_DIRTY_RING case is missing. > > > > > > > > No stub is needed. kvm_dirty_ring_check_request() isn't called from > > > > common code, and should not (and isn't unless I'm missing something) > > > > be called from arch code unless CONFIG_HAVE_KVM_DIRTY_RING=y. > > > > > > > > x86 and arm64 are the only users, and they both select > > > > HAVE_KVM_DIRTY_RING unconditionally when KVM is enabled. > > > > > > Yes, it is at present not called from anywhere other than x86 and arm64. > > > But I still think since it is a common helper, better to have a stub. > > > > Why? It buys us nothing other than dead code, and even worse it could let > > a bug that would otherwise be caught during build time escape to run time. > > Agree, it buys nothing now:) It just came up while I was playing with a custom > build without HAVE_KVM_DIRTY_RING. Since all other functions there has a stub > just thought it would make it easier for future common usage. We could very well > leave it till that comes up as well. Stubs are typically only added when they are strictly necessary. Providing a stub would make things "easier" in the sense that it could theoretically avoid a build error, but as above, in many cases we _want_ build errors when new code behaves in a way that diverges from what's expected/established.
