X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=mm%2Fmemory-failure.c;h=44c6bd201d3a1cac7120527b45e2a86f5f77abff;hb=cee5aa1f81b1e88d8de05df226bfd207041954c2;hp=c6399e32893178b835457388371e8e4f85512361;hpb=5e2aa2ed08e2e280121dc7cf5609c87d464f12ef;p=firefly-linux-kernel-4.4.55.git

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index c6399e328931..44c6bd201d3a 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -435,7 +435,7 @@ static void collect_procs_anon(struct page *page, struct list_head *to_kill,
 	if (av == NULL)	/* Not actually mapped anymore */
 		return;
 
-	pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+	pgoff = page_to_pgoff(page);
 	read_lock(&tasklist_lock);
 	for_each_process (tsk) {
 		struct anon_vma_chain *vmac;
@@ -469,7 +469,7 @@ static void collect_procs_file(struct page *page, struct list_head *to_kill,
 	mutex_lock(&mapping->i_mmap_mutex);
 	read_lock(&tasklist_lock);
 	for_each_process(tsk) {
-		pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+		pgoff_t pgoff = page_to_pgoff(page);
 		struct task_struct *t = task_early_kill(tsk, force_early);
 
 		if (!t)
@@ -895,7 +895,13 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
 	struct page *hpage = *hpagep;
 	struct page *ppage;
 
-	if (PageReserved(p) || PageSlab(p) || !PageLRU(p))
+	/*
+	 * Here we are interested only in user-mapped pages, so skip any
+	 * other types of pages.
+	 */
+	if (PageReserved(p) || PageSlab(p))
+		return SWAP_SUCCESS;
+	if (!(PageLRU(hpage) || PageHuge(p)))
 		return SWAP_SUCCESS;
 
 	/*
@@ -905,8 +911,10 @@ static int hwpoison_user_mappings(struct page *p, unsigned long pfn,
 	if (!page_mapped(hpage))
 		return SWAP_SUCCESS;
 
-	if (PageKsm(p))
+	if (PageKsm(p)) {
+		pr_err("MCE %#lx: can't handle KSM pages.\n", pfn);
 		return SWAP_FAIL;
+	}
 
 	if (PageSwapCache(p)) {
 		printk(KERN_ERR
@@ -1164,6 +1172,16 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
 
 	lock_page(hpage);
 
+	/*
+	 * The page could have changed compound pages during the locking.
+	 * If this happens just bail out.
+	 */
+	if (compound_head(p) != hpage) {
+		action_result(pfn, "different compound page after locking", IGNORED);
+		res = -EBUSY;
+		goto out;
+	}
+
 	/*
 	 * We use page flags to determine what action should be taken, but
 	 * the flags can be modified by the error containment action.  One
@@ -1229,7 +1247,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
 	 */
 	if (hwpoison_user_mappings(p, pfn, trapno, flags, &hpage)
 	    != SWAP_SUCCESS) {
-		printk(KERN_ERR "MCE %#lx: cannot unmap page, give up\n", pfn);
+		action_result(pfn, "unmapping failed", IGNORED);
 		res = -EBUSY;
 		goto out;
 	}