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