@@ -281,13 +281,12 @@ static void record_hugetlb_cgroup_unchar
&h_cg->rsvd_hugepage[hstate_index(h)];
nrg->css = &h_cg->css;
/*
- * The caller (hugetlb_reserve_pages now) will only hold one
- * h_cg->css reference for the whole contiguous reservation
- * region. But this area might be scattered when there are
- * already some file_regions reside in it. As a result, many
- * file_regions may share only one h_cg->css reference. In
- * order to ensure that one file_region must hold and only
- * hold one h_cg->css reference, we should do css_get for
+ * The caller will hold exactly one h_cg->css reference for the
+ * whole contiguous reservation region. But this area might be
+ * scattered when there are already some file_regions reside in
+ * it. As a result, many file_regions may share only one css
+ * reference. In order to ensure that one file_region must hold
+ * exactly one h_cg->css reference, we should do css_get for
* each file_region and leave the reference held by caller
* untouched.
*/
@@ -403,8 +403,7 @@ void hugetlb_cgroup_uncharge_file_region
nr_pages * resv->pages_per_hpage);
/*
* Only do css_put(rg->css) when we delete the entire region
- * because one file_region must hold and only hold one rg->css
- * reference.
+ * because one file_region must hold exactly one css reference.
*/
if (region_del)
css_put(rg->css);
The patch titled Subject: hugetlb_cgroup: fix imbalanced css_get and css_put pair for shared mappings has been added to the -mm tree. Its filename is hugetlb_cgroup-fix-imbalanced-css_get-and-css_put-pair-for-shared-mappings-v3.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/hugetlb_cgroup-fix-imbalanced-css_get-and-css_put-pair-for-shared-mappings-v3.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/hugetlb_cgroup-fix-imbalanced-css_get-and-css_put-pair-for-shared-mappings-v3.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Miaohe Lin <linmiaohe@huawei.com> Subject: hugetlb_cgroup: fix imbalanced css_get and css_put pair for shared mappings reshape some comments, per Mike Link: https://lkml.kernel.org/r/20210316023002.53921-1-linmiaohe@huawei.com Fixes: 075a61d07a8e ("hugetlb_cgroup: add accounting for shared mappings") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Reported-by: kernel test robot <lkp@intel.com> (auto build test ERROR) Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Wanpeng Li <liwp.linux@gmail.com> Cc: Mina Almasry <almasrymina@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> --- mm/hugetlb.c | 13 ++++++------- mm/hugetlb_cgroup.c | 3 +-- 2 files changed, 7 insertions(+), 9 deletions(-)