Re: [PATCH RFC v9 13/25] mm: kpkeys: Introduce early page table allocator

On 8/18/26 07:08, Kevin Brodsky wrote:

This patch addresses the second category: PTPs allocated via memblock.
Such PTPs are notably used to create the linear map. Protecting them as
soon as they are allocated would require modifying the linear map while
it is being created, which seems at best difficult. Instead, a
simple allocator is introduced, obtaining pages from memblock and
keeping track of all allocated ranges to set their pkey once it is
safe to do so.

What makes setting a pkey on the memory "unsafe"? Is there something
preventing just making access permissive during boot?