On Tue, 23 May 2023, Matthew Wilcox wrote: > On Mon, May 22, 2023 at 11:39:27AM -0700, David Rientjes wrote: > > I think VM_BUG_ON*() and friends are used to crash the kernel for > > debugging so that we get a crash dump and because some variants don't > > exist for VM_WARN_ON(). There's no VM_WARN_ON_PAGE(), for example, unless > > implicitly converted with this patch. > > It could be added, but there's already a VM_WARN_ON_FOLIO() and > VM_WARN_ON_ONCE_PAGE(), so hopefully we just keep converting code > to folios until nobody notices that we might need such a thing. > Yeah, the lack of VM_WARN variants for VM_BUG_ON_MM or VM_BUG_ON_VMA are probably better examples. But it looks like we're converging toward eliminating VM_BUG_ON* variants entirely and relying on kernel.panic_on_warn to do the BUG_ON() behavior if we want to opt into that. So this will be a useful cleanup.
