X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=mm%2Fmemory.c;h=d037e84cdcf33d0b1ec6a38692e9d714e3ba4694;hb=a1bd55431114f35158e3c5a46db754fd74c55889;hp=adf9b9ef8277da3dab7500ee26b0067bd6763e71;hpb=02d5e016800d082058b3d3b7c3ede136cdc6ddcb;p=platform%2Fkernel%2Flinux-rpi.git

diff --git a/mm/memory.c b/mm/memory.c
index adf9b9e..d037e84 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1301,6 +1301,17 @@ copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma)
 	return ret;
 }
 
+/* Whether we should zap all COWed (private) pages too */
+static inline bool should_zap_cows(struct zap_details *details)
+{
+	/* By default, zap all pages */
+	if (!details)
+		return true;
+
+	/* Or, we zap COWed pages only if the caller wants to */
+	return !details->check_mapping;
+}
+
 static unsigned long zap_pte_range(struct mmu_gather *tlb,
 				struct vm_area_struct *vma, pmd_t *pmd,
 				unsigned long addr, unsigned long end,
@@ -1396,16 +1407,18 @@ again:
 			continue;
 		}
 
-		/* If details->check_mapping, we leave swap entries. */
-		if (unlikely(details))
-			continue;
-
-		if (!non_swap_entry(entry))
+		if (!non_swap_entry(entry)) {
+			/* Genuine swap entry, hence a private anon page */
+			if (!should_zap_cows(details))
+				continue;
 			rss[MM_SWAPENTS]--;
-		else if (is_migration_entry(entry)) {
+		} else if (is_migration_entry(entry)) {
 			struct page *page;
 
 			page = pfn_swap_entry_to_page(entry);
+			if (details && details->check_mapping &&
+			    details->check_mapping != page_rmapping(page))
+				continue;
 			rss[mm_counter(page)]--;
 		}
 		if (unlikely(!free_swap_and_cache(entry)))
@@ -3861,11 +3874,20 @@ static vm_fault_t __do_fault(struct vm_fault *vmf)
 		return ret;
 
 	if (unlikely(PageHWPoison(vmf->page))) {
-		if (ret & VM_FAULT_LOCKED)
-			unlock_page(vmf->page);
-		put_page(vmf->page);
+		struct page *page = vmf->page;
+		vm_fault_t poisonret = VM_FAULT_HWPOISON;
+		if (ret & VM_FAULT_LOCKED) {
+			if (page_mapped(page))
+				unmap_mapping_pages(page_mapping(page),
+						    page->index, 1, false);
+			/* Retry if a clean page was removed from the cache. */
+			if (invalidate_inode_page(page))
+				poisonret = VM_FAULT_NOPAGE;
+			unlock_page(page);
+		}
+		put_page(page);
 		vmf->page = NULL;
-		return VM_FAULT_HWPOISON;
+		return poisonret;
 	}
 
 	if (unlikely(!(ret & VM_FAULT_LOCKED)))
@@ -3907,6 +3929,15 @@ vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page)
 		return ret;
 
 	/*
+	 * Just backoff if any subpage of a THP is corrupted otherwise
+	 * the corrupted page may mapped by PMD silently to escape the
+	 * check.  This kind of THP just can be PTE mapped.  Access to
+	 * the corrupted subpage should trigger SIGBUS as expected.
+	 */
+	if (unlikely(PageHasHWPoisoned(page)))
+		return ret;
+
+	/*
 	 * Archs like ppc64 need additional space to store information
 	 * related to pte entry. Use the preallocated table for that.
 	 */
@@ -4040,9 +4071,12 @@ vm_fault_t finish_fault(struct vm_fault *vmf)
 		}
 	}
 
-	/* See comment in handle_pte_fault() */
+	/*
+	 * See comment in handle_pte_fault() for how this scenario happens, we
+	 * need to return NOPAGE so that we drop this page.
+	 */
 	if (pmd_devmap_trans_unstable(vmf->pmd))
-		return 0;
+		return VM_FAULT_NOPAGE;
 
 	vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd,
 				      vmf->address, &vmf->ptl);
@@ -4059,7 +4093,7 @@ vm_fault_t finish_fault(struct vm_fault *vmf)
 }
 
 static unsigned long fault_around_bytes __read_mostly =
-	rounddown_pow_of_two(65536);
+	rounddown_pow_of_two(4096);
 
 #ifdef CONFIG_DEBUG_FS
 static int fault_around_bytes_get(void *data, u64 *val)
@@ -4460,6 +4494,19 @@ static vm_fault_t create_huge_pud(struct vm_fault *vmf)
 	defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)
 	/* No support for anonymous transparent PUD pages yet */
 	if (vma_is_anonymous(vmf->vma))
+		return VM_FAULT_FALLBACK;
+	if (vmf->vma->vm_ops->huge_fault)
+		return vmf->vma->vm_ops->huge_fault(vmf, PE_SIZE_PUD);
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+	return VM_FAULT_FALLBACK;
+}
+
+static vm_fault_t wp_huge_pud(struct vm_fault *vmf, pud_t orig_pud)
+{
+#if defined(CONFIG_TRANSPARENT_HUGEPAGE) &&			\
+	defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)
+	/* No support for anonymous transparent PUD pages yet */
+	if (vma_is_anonymous(vmf->vma))
 		goto split;
 	if (vmf->vma->vm_ops->huge_fault) {
 		vm_fault_t ret = vmf->vma->vm_ops->huge_fault(vmf, PE_SIZE_PUD);
@@ -4470,19 +4517,7 @@ static vm_fault_t create_huge_pud(struct vm_fault *vmf)
 split:
 	/* COW or write-notify not handled on PUD level: split pud.*/
 	__split_huge_pud(vmf->vma, vmf->pud, vmf->address);
-#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
-	return VM_FAULT_FALLBACK;
-}
-
-static vm_fault_t wp_huge_pud(struct vm_fault *vmf, pud_t orig_pud)
-{
-#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	/* No support for anonymous transparent PUD pages yet */
-	if (vma_is_anonymous(vmf->vma))
-		return VM_FAULT_FALLBACK;
-	if (vmf->vma->vm_ops->huge_fault)
-		return vmf->vma->vm_ops->huge_fault(vmf, PE_SIZE_PUD);
-#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE && CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
 	return VM_FAULT_FALLBACK;
 }
 
@@ -5256,7 +5291,7 @@ void __might_fault(const char *file, int line)
 		return;
 	if (pagefault_disabled())
 		return;
-	__might_sleep(file, line, 0);
+	__might_sleep(file, line);
 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP)
 	if (current->mm)
 		might_lock_read(&current->mm->mmap_lock);
@@ -5436,6 +5471,8 @@ long copy_huge_page_from_user(struct page *dst_page,
 		if (rc)
 			break;
 
+		flush_dcache_page(subpage);
+
 		cond_resched();
 	}
 	return ret_val;