On Wed, May 18, 2022 at 04:51:06PM +0200, David Hildenbrand wrote: > yes, I talked about the involved challenges, especially, how malicious > user space can trigger allocation of almost elusively page tables and > essentially consume a lot of unmovable+unswappable memory and even store > secrets in the page table structure. There are a lot of ways for userspace to consume a large amount of kernel memory. For example, one can open a file and set file locks on alternate bytes. We generally handle this by accounting the memory to the process and let the OOM killer, rlimits, memcg or other mechanism take care of it. Just because page tables are (generally) reclaimable doesn't mean we need to treat them specially.
