diff options
| author | Rik van Riel | 2023-10-05 23:59:07 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman | 2023-11-02 09:35:24 +0100 |
| commit | b1b2750de12382803f255ef7e5b40de16030e309 (patch) | |
| tree | bbd5adb2fda1d04ce2475c2ee2419ede4e71cfba /include | |
| parent | c9b066f6920d5e9d68258d0c708bef709406918c (diff) | |
hugetlbfs: extend hugetlb_vma_lock to private VMAs
commit bf4916922c60f43efaa329744b3eef539aa6a2b2 upstream.
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.
Link: https://lkml.kernel.org/r/20231006040020.3677377-3-riel@surriel.com
Fixes: 04ada095dcfc ("hugetlb: don't delete vma_lock in hugetlb MADV_DONTNEED processing")
Signed-off-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/hugetlb.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 58b53d08f2c8..e46f6b49eb38 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -70,6 +70,7 @@ struct resv_map { long adds_in_progress; struct list_head region_cache; long region_cache_count; + struct rw_semaphore rw_sema; #ifdef CONFIG_CGROUP_HUGETLB /* * On private mappings, the counter to uncharge reservations is stored @@ -879,6 +880,11 @@ static inline bool hugepage_migration_supported(struct hstate *h) return arch_hugetlb_migration_supported(h); } +static inline bool __vma_private_lock(struct vm_area_struct *vma) +{ + return (!(vma->vm_flags & VM_MAYSHARE)) && vma->vm_private_data; +} + /* * Movability check is different as compared to migration check. * It determines whether or not a huge page should be placed on |