Re: [PATCH v8 2/4] userfaultfd: split mwriteprotect_range()

On Tue, Jan 24, 2023 at 01:43:21PM +0500, Muhammad Usama Anjum wrote:

Split mwriteprotect_range() to create a unlocked version. This will be used in the next patch to write protect a memory area. Add a helper function, wp_range_async() as well.

Signed-off-by: Muhammad Usama Anjum usama.anjum@collabora.com

IIUC this patch is not needed. You have a stable vma, so I think you can directly use uffd_wp_range(), while most of the mwriteprotect_range() is not needed.

There's one trivial detail of ignoring userfaultfd_ctx->mmap_changing when it's set to true, but I don't think it applies here either because it was used to resolve a problem in uffd non-cooperative mode on the predictable behavior of events, here I don't think it matters a lot either.