[merged] mm-gup-fix-potential-pgmap-refcnt-leak-in-__gup_device_huge.patch removed from -mm tree

[merged] mm-gup-fix-potential-pgmap-refcnt-leak-in-__gup_device_huge.patch removed from -mm tree

[akpm]

The patch titled
     Subject: mm: gup: fix potential pgmap refcnt leak in __gup_device_huge()
has been removed from the -mm tree.  Its filename was
     mm-gup-fix-potential-pgmap-refcnt-leak-in-__gup_device_huge.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: Miaohe Lin <linmiaohe@huawei.com>
Subject: mm: gup: fix potential pgmap refcnt leak in __gup_device_huge()

When failed to try_grab_page, put_dev_pagemap() is missed.  So pgmap
refcnt will leak in this case.  Also we remove the check for pgmap against
NULL as it's also checked inside the put_dev_pagemap().

[akpm@linux-foundation.org: simplify, cleanup]
[akpm@linux-foundation.org: fix return value]
Link: https://lkml.kernel.org/r/20210807093620.21347-5-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Fixes: 3faa52c03f44 ("mm/gup: track FOLL_PIN pages")
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/gup.c |   12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

--- a/mm/gup.c~mm-gup-fix-potential-pgmap-refcnt-leak-in-__gup_device_huge
+++ a/mm/gup.c
@@ -2240,6 +2240,7 @@ static int __gup_device_huge(unsigned lo
 {
 	int nr_start = *nr;
 	struct dev_pagemap *pgmap = NULL;
+	int ret = 1;
 
 	do {
 		struct page *page = pfn_to_page(pfn);
@@ -2247,21 +2248,22 @@ static int __gup_device_huge(unsigned lo
 		pgmap = get_dev_pagemap(pfn, pgmap);
 		if (unlikely(!pgmap)) {
 			undo_dev_pagemap(nr, nr_start, flags, pages);
-			return 0;
+			ret = 0;
+			break;
 		}
 		SetPageReferenced(page);
 		pages[*nr] = page;
 		if (unlikely(!try_grab_page(page, flags))) {
 			undo_dev_pagemap(nr, nr_start, flags, pages);
-			return 0;
+			ret = 0;
+			break;
 		}
 		(*nr)++;
 		pfn++;
 	} while (addr += PAGE_SIZE, addr != end);
 
-	if (pgmap)
-		put_dev_pagemap(pgmap);
-	return 1;
+	put_dev_pagemap(pgmap);
+	return ret;
 }
 
 static int __gup_device_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr,
_

Patches currently in -mm which might be from linmiaohe@huawei.com are

mm-page_allocc-avoid-accessing-uninitialized-pcp-page-migratetype.patch
mm-memory_hotplug-use-helper-zone_is_zone_device-to-simplify-the-code.patch
mm-memory_hotplug-make-hwpoisoned-dirty-swapcache-pages-unmovable.patch
mm-zsmallocc-close-race-window-between-zs_pool_dec_isolated-and-zs_unregister_migration.patch
mm-zsmallocc-combine-two-atomic-ops-in-zs_pool_dec_isolated.patch