On Wed, Jan 12, 2022 at 07:14:34PM -0800, Peter Collingbourne wrote: > It has been reported that the tag setting operation on newly-allocated > pages can cause the page flags to be corrupted when performed > concurrently with other flag updates as a result of the use of > non-atomic operations. Fix the problem by using a compare-exchange > loop to update the tag. I really dislike it that kasan has taken some page flags for its use. I would much prefer it if kasan used some page_ext_flags. It's somewhat slower to access them, and they take up a bit of extra space (unless you already have CONFIG_PAGE_EXTENSION enabled). But page flags are a really scarce resource and kasan has taken 9.
