diff options
Diffstat (limited to 'include/linux/mm.h')
| -rw-r--r-- | include/linux/mm.h | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 69fa3df9e712..2b17d2fca429 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -446,7 +446,6 @@ static inline void page_mapcount_reset(struct page *page) static inline int page_mapcount(struct page *page) { - VM_BUG_ON_PAGE(PageSlab(page), page); return atomic_read(&page->_mapcount) + 1; } @@ -1124,6 +1123,10 @@ void unmap_vmas(struct mmu_gather *tlb, struct vm_area_struct *start_vma, * followed by taking the mmap_sem for writing before modifying the * vmas or anything the coredump pretends not to change from under it. * + * It also has to be called when mmgrab() is used in the context of + * the process, but then the mm_count refcount is transferred outside + * the context of the process to run down_write() on that pinned mm. + * * NOTE: find_extend_vma() called from GUP context is the only place * that can modify the "mm" (notably the vm_start/end) under mmap_sem * for reading and outside the context of the process, so it is also |