diff options
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/mm/memory.c b/mm/memory.c index d14b251a25a..2302d228fe0 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1151,7 +1151,7 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, * be processed until returning to user space. */ if (unlikely(test_tsk_thread_flag(tsk, TIF_MEMDIE))) - return -ENOMEM; + return i ? i : -ENOMEM; if (write) foll_flags |= FOLL_WRITE; @@ -1697,8 +1697,19 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma, struct page *dirty_page = NULL; old_page = vm_normal_page(vma, address, orig_pte); - if (!old_page) + if (!old_page) { + /* + * VM_MIXEDMAP !pfn_valid() case + * + * We should not cow pages in a shared writeable mapping. + * Just mark the pages writable as we can't do any dirty + * accounting on raw pfn maps. + */ + if ((vma->vm_flags & (VM_WRITE|VM_SHARED)) == + (VM_WRITE|VM_SHARED)) + goto reuse; goto gotten; + } /* * Take out anonymous pages first, anonymous shared vmas are @@ -1751,6 +1762,7 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma, } if (reuse) { +reuse: flush_cache_page(vma, address, pte_pfn(orig_pte)); entry = pte_mkyoung(orig_pte); entry = maybe_mkwrite(pte_mkdirty(entry), vma); |