The patch titled Subject: hugetlbfs-use-i_mmap_rwsem-to-fix-page-fault-truncate-race-v3 has been added to the -mm tree. Its filename is hugetlbfs-use-i_mmap_rwsem-to-fix-page-fault-truncate-race-v3.patch
This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/hugetlbfs-use-i_mmap_rwsem-to-fix-p... and later at http://ozlabs.org/~akpm/mmotm/broken-out/hugetlbfs-use-i_mmap_rwsem-to-fix-p...
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------------------------------------------------------ From: Mike Kravetz mike.kravetz@oracle.com Subject: hugetlbfs-use-i_mmap_rwsem-to-fix-page-fault-truncate-race-v3
Incorporated suggestions from Kirill. Code change to hold i_mmap_rwsem for duration of copy in copy_hugetlb_page_range. Took i_mmap_rwsem in hugetlbfs_evict_inode to be consistent with other callers. Other changes were to documentation/comments.
Link: http://lkml.kernel.org/r/20181222223013.22193-3-mike.kravetz@oracle.com Cc: stable@vger.kernel.org Fixes: ebed4bfc8da8 ("hugetlb: fix absurd HugePages_Rsvd") Signed-off-by: Mike Kravetz mike.kravetz@oracle.com Cc: Andrea Arcangeli aarcange@redhat.com Cc: "Aneesh Kumar K . V" aneesh.kumar@linux.vnet.ibm.com Cc: Davidlohr Bueso dave@stgolabs.net Cc: Hugh Dickins hughd@google.com Cc: "Kirill A . Shutemov" kirill.shutemov@linux.intel.com Cc: Michal Hocko mhocko@kernel.org Cc: Naoya Horiguchi n-horiguchi@ah.jp.nec.com Cc: Prakash Sangappa prakash.sangappa@oracle.com Signed-off-by: Andrew Morton akpm@linux-foundation.org ---
--- a/fs/hugetlbfs/inode.c~hugetlbfs-use-i_mmap_rwsem-to-fix-page-fault-truncate-race-v3 +++ a/fs/hugetlbfs/inode.c @@ -462,9 +462,20 @@ static void remove_inode_hugepages(struc
static void hugetlbfs_evict_inode(struct inode *inode) { + struct address_space *mapping = inode->i_mapping; struct resv_map *resv_map;
+ /* + * The vfs layer guarantees that there are no other users of this + * inode. Therefore, it would be safe to call remove_inode_hugepages + * without holding i_mmap_rwsem. We acquire and hold here to be + * consistent with other callers. Since there will be no contention + * on the semaphore, overhead is negligible. + */ + i_mmap_lock_write(mapping); remove_inode_hugepages(inode, 0, LLONG_MAX); + i_mmap_unlock_write(mapping); + resv_map = (struct resv_map *)inode->i_mapping->private_data; /* root inode doesn't have the resv_map, so we should check it */ if (resv_map) _
Patches currently in -mm which might be from mike.kravetz@oracle.com are
hugetlbfs-use-i_mmap_rwsem-for-more-pmd-sharing-synchronization.patch hugetlbfs-use-i_mmap_rwsem-for-more-pmd-sharing-synchronization-fix.patch hugetlbfs-use-i_mmap_rwsem-to-fix-page-fault-truncate-race.patch hugetlbfs-use-i_mmap_rwsem-to-fix-page-fault-truncate-race-v3.patch