Re: [PATCH 4/4] mm: delay page_remove_rmap() until after the TLB has been flushed

Nadav Amit
2022-11-08T21:05:47Z

On Nov 8, 2022, at 11:41 AM, Linus Torvalds <torvalds@linux-foundation.org> wrote:

> When we remove a page table entry, we are very careful to only free the
> page after we have flushed the TLB, because other CPUs could still be
> using the page through stale TLB entries until after the flush.

The patches (all 4) look fine to me.

I mean there are minor issues here and there, like s390’s tlb_flush_rmaps()
that can have VM_WARN_ON(1);the generic tlb_flush_rmaps() that is missing an
empty line after the ‘page' variable definition; or perhaps using __bitwise
for sparse (as David pointed) — but it can all be addressed later.