On Thu 22-08-24 14:56:08, Linus Torvalds wrote: > On Thu, 22 Aug 2024 at 14:40, Linus Torvalds > <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > > > > I did find three cases of kvcalloc(NOFAIL) in the nouveau driver and > > one in erofs. It's not clear that any of them make much sense (or that > > the erofs one is actually a large allocation). > > Oh, and I missed one in btrfs because it needed five lines of context > due to being the allocation from hell. > > That said, yes, the vmalloc case at least has no fragmentation issues, > but I do think even that needs to be size limited for sanity. > > The size limit might be larger than a couple of pages, but not > _hugely_ larger. You can't just say "I want a megabyte, and you can't > fail me". That kind of code is garbage, and needs to be called out for > being garbage. yes, no objection here. Our current limits are too large for any practical purpose. We still need a strategy how to communicate that the size is not supported though. Just returning NULL is IMHO bad thing because it adds potentially silent failure. In other subthread I was contemplating about OOPS_ON which would simply terminate the user context and kill it right away. What do you think about something like that? -- Michal Hocko SUSE Labs
