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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2020-12-29 15:45:49 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-12-29 15:45:49 -0800 |
| commit | 139711f033f636cc78b6aaf7363252241b9698ef (patch) | |
| tree | 56cedce3b399e22eb0fee8f592ad77c823129a8b /mm/hugetlb.c | |
| parent | dea8dcf2a9fa8cc540136a6cd885c3beece16ec3 (diff) | |
| parent | 1f3147b49d75b47b6be54a1e6dfa87a4921e1e51 (diff) | |
Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
"16 patches
Subsystems affected by this patch series: mm (selftests, hugetlb,
pagecache, mremap, kasan, and slub), kbuild, checkpatch, misc, and
lib"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm: slub: call account_slab_page() after slab page initialization
zlib: move EXPORT_SYMBOL() and MODULE_LICENSE() out of dfltcc_syms.c
lib/zlib: fix inflating zlib streams on s390
lib/genalloc: fix the overflow when size is too big
kdev_t: always inline major/minor helper functions
sizes.h: add SZ_8G/SZ_16G/SZ_32G macros
local64.h: make <asm/local64.h> mandatory
kasan: fix null pointer dereference in kasan_record_aux_stack
mm: generalise COW SMC TLB flushing race comment
mm/mremap.c: fix extent calculation
mm: memmap defer init doesn't work as expected
mm: add prototype for __add_to_page_cache_locked()
checkpatch: prefer strscpy to strlcpy
Revert "kbuild: avoid static_assert for genksyms"
mm/hugetlb: fix deadlock in hugetlb_cow error path
selftests/vm: fix building protection keys test
Diffstat (limited to 'mm/hugetlb.c')
| -rw-r--r-- | mm/hugetlb.c | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index cbf32d2824fd..a2602969873d 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -4105,10 +4105,30 @@ retry_avoidcopy: * may get SIGKILLed if it later faults. */ if (outside_reserve) { + struct address_space *mapping = vma->vm_file->f_mapping; + pgoff_t idx; + u32 hash; + put_page(old_page); BUG_ON(huge_pte_none(pte)); + /* + * Drop hugetlb_fault_mutex and i_mmap_rwsem before + * unmapping. unmapping needs to hold i_mmap_rwsem + * in write mode. Dropping i_mmap_rwsem in read mode + * here is OK as COW mappings do not interact with + * PMD sharing. + * + * Reacquire both after unmap operation. + */ + idx = vma_hugecache_offset(h, vma, haddr); + hash = hugetlb_fault_mutex_hash(mapping, idx); + mutex_unlock(&hugetlb_fault_mutex_table[hash]); + i_mmap_unlock_read(mapping); + unmap_ref_private(mm, vma, old_page, haddr); - BUG_ON(huge_pte_none(pte)); + + i_mmap_lock_read(mapping); + mutex_lock(&hugetlb_fault_mutex_table[hash]); spin_lock(ptl); ptep = huge_pte_offset(mm, haddr, huge_page_size(h)); if (likely(ptep && |