On Mon, 9 Apr 2012 14:59:00 -0500 Will Drewry <wad@xxxxxxxxxxxx> wrote: > >> I think this gives userspace an easy way of causing page allocation > >> failure warnings, by permitting large kmalloc() attempts. __Add > >> __GFP_NOWARN? > > > > Max is 32kb. sk_attach_filter() in net/core/filter.c is worse, > > it allocates up to 512kb before even checking the length. > > > > What about using GFP_USER (and adding __GFP_NOWARN to GFP_USER) instead? > > It looks like GFP_USER|__GFP_NOWARN would make sense here. I'll change it. I'm not really sure why GFP_USER exists. It's very rarely used, and most usages are probably inappropriate. To me it means "same as GFP_HIGHUSER, only don't use highmem". That's relevant to blockdev pagecache and nothing else as far as I can tell. And good luck working out what the __GFP_HARDWALL does ;) This is a regular old allocation of kernel memory - the thing to use here is GFP_KERNEL|__GFP_NOWARN. (I'm surprised that we didn't remove __GFP_NOWARN ages ago - warning by default is pretty obnoxious. But the warning continues to be occasionally useful and false positives are rare). -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
