On Fri, 1 Nov 2024 at 08:46, Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> wrote: > > Each of which acquire the mmap write lock before doing so. Despite this, we > maintain code that acquires a page table lock in the expand_upwards() and > expand_downwards() code, stating that we hold a shared mmap lock and thus > this is necessary. > > It is not, we do not have to worry about concurrent VMA expansions so we > can simply drop this, and update comments accordingly. > > We do not even need be concerned with racing page faults, as > vma_start_write() is invoked in both cases. Ack, seems ObviouslyCorrect(tm). Linus