On 09/20/23 00:09, Rik van Riel wrote: > On Wed, 2023-09-20 at 04:57 +0100, Matthew Wilcox wrote: > > On Tue, Sep 19, 2023 at 10:16:09PM -0400, riel@xxxxxxxxxxx wrote: > > > From: Rik van Riel <riel@xxxxxxxxxxx> > > > > > > Extend the locking scheme used to protect shared hugetlb mappings > > > from truncate vs page fault races, in order to protect private > > > hugetlb mappings (with resv_map) against MADV_DONTNEED. > > > > > > Add a read-write semaphore to the resv_map data structure, and > > > use that from the hugetlb_vma_(un)lock_* functions, in preparation > > > for closing the race between MADV_DONTNEED and page faults. > > > > This feels an awful lot like the invalidate_lock in struct > > address_space > > which was recently added by Jan Kara. > > > Indeed it does. > > It might be even nicer if we could replace the hugetlb_vma_lock > special logic with the invalidate_lock for hugetlbfs. > > Mike, can you think of any reason why the hugetlb_vma_lock logic > should not be replaced with the invalidate_lock? > > If not, I'd be happy to implement that. > Sorry Rik, I have some other things that need immediate attention and have not had a chance to take a close look here. I'll take a closer look later (my) today or tomorrow. -- Mike Kravetz
