The sysfs group per_node_hstate_attr_group and hstate_demote_attr_group
when h->demote_order != 0 are created in hugetlb_register_node(). But
these sysfs groups are not removed when unregister the node, thus sysfs
group is leaked. Using sysfs_remove_group() to fix this issue.
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
---
mm/hugetlb.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index b69d7808f457..e1356ad57087 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3850,12 +3850,18 @@ static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent,
}
if (h->demote_order) {
- if (sysfs_create_group(hstate_kobjs[hi],
- &hstate_demote_attr_group))
+ retval = sysfs_create_group(hstate_kobjs[hi],
+ &hstate_demote_attr_group);
+ if (retval) {
pr_warn("HugeTLB unable to create demote interfaces for %s\n", h->name);
+ sysfs_remove_group(hstate_kobjs[hi], hstate_attr_group);
+ kobject_put(hstate_kobjs[hi]);
+ hstate_kobjs[hi] = NULL;
+ return retval;
+ }
}
- return retval;
+ return 0;
}
static void __init hugetlb_sysfs_init(void)
@@ -3941,10 +3947,15 @@ static void hugetlb_unregister_node(struct node *node)
for_each_hstate(h) {
int idx = hstate_index(h);
- if (nhs->hstate_kobjs[idx]) {
- kobject_put(nhs->hstate_kobjs[idx]);
- nhs->hstate_kobjs[idx] = NULL;
- }
+ struct kobject *hstate_kobj = nhs->hstate_kobjs[idx];
+
+ if (!hstate_kobj)
+ continue;
+ if (h->demote_order)
+ sysfs_remove_group(hstate_kobj, &hstate_demote_attr_group);
+ sysfs_remove_group(hstate_kobj, &per_node_hstate_attr_group);
+ kobject_put(hstate_kobj);
+ nhs->hstate_kobjs[idx] = NULL;
}
kobject_put(nhs->hugepages_kobj);
--
2.23.0
On 8/16/2022 9:05 PM, Miaohe Lin wrote:
> The sysfs group per_node_hstate_attr_group and hstate_demote_attr_group
> when h->demote_order != 0 are created in hugetlb_register_node(). But
> these sysfs groups are not removed when unregister the node, thus sysfs
> group is leaked. Using sysfs_remove_group() to fix this issue.
>
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Fengwei Yin <fengwei.yin@intel.com>
Regards
Yin, Fengwei
> ---
> mm/hugetlb.c | 25 ++++++++++++++++++-------
> 1 file changed, 18 insertions(+), 7 deletions(-)
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index b69d7808f457..e1356ad57087 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -3850,12 +3850,18 @@ static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent,
> }
>
> if (h->demote_order) {
> - if (sysfs_create_group(hstate_kobjs[hi],
> - &hstate_demote_attr_group))
> + retval = sysfs_create_group(hstate_kobjs[hi],
> + &hstate_demote_attr_group);
> + if (retval) {
> pr_warn("HugeTLB unable to create demote interfaces for %s\n", h->name);
> + sysfs_remove_group(hstate_kobjs[hi], hstate_attr_group);
> + kobject_put(hstate_kobjs[hi]);
> + hstate_kobjs[hi] = NULL;
> + return retval;
> + }
> }
>
> - return retval;
> + return 0;
> }
>
> static void __init hugetlb_sysfs_init(void)
> @@ -3941,10 +3947,15 @@ static void hugetlb_unregister_node(struct node *node)
>
> for_each_hstate(h) {
> int idx = hstate_index(h);
> - if (nhs->hstate_kobjs[idx]) {
> - kobject_put(nhs->hstate_kobjs[idx]);
> - nhs->hstate_kobjs[idx] = NULL;
> - }
> + struct kobject *hstate_kobj = nhs->hstate_kobjs[idx];
> +
> + if (!hstate_kobj)
> + continue;
> + if (h->demote_order)
> + sysfs_remove_group(hstate_kobj, &hstate_demote_attr_group);
> + sysfs_remove_group(hstate_kobj, &per_node_hstate_attr_group);
> + kobject_put(hstate_kobj);
> + nhs->hstate_kobjs[idx] = NULL;
> }
>
> kobject_put(nhs->hugepages_kobj);
Hi Miaohe,
On 8/16/2022 9:05 PM, Miaohe Lin wrote:
> }
>
> if (h->demote_order) {
> - if (sysfs_create_group(hstate_kobjs[hi],
> - &hstate_demote_attr_group))
> + retval = sysfs_create_group(hstate_kobjs[hi],
> + &hstate_demote_attr_group);
What about add one more:
just return if hstate_attr_group creating failed:
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 0aee2f3ae15c..a67ef4b4eb3f 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3845,6 +3845,7 @@ static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent,
if (retval) {
kobject_put(hstate_kobjs[hi]);
hstate_kobjs[hi] = NULL;
+ return retval;
}
Once hstate_kobjs[hi] is set to NULL, hstate_demote_attr_group creating will
fail as well. Thanks.
Regards
Yin, Fengwei
> + if (retval) {
> pr_warn("HugeTLB unable to create demote interfaces for %s\n", h->name);
> + sysfs_remove_group(hstate_kobjs[hi], hstate_attr_group);
> + kobject_put(hstate_kobjs[hi]);
> + hstate_kobjs[hi] = NULL;
> + return retval;
> + }
> }
On 8/17/2022 5:41 PM, Yin, Fengwei wrote:
> Hi Miaohe,
>
> On 8/16/2022 9:05 PM, Miaohe Lin wrote:
>> }
>>
>> if (h->demote_order) {
>> - if (sysfs_create_group(hstate_kobjs[hi],
>> - &hstate_demote_attr_group))
>> + retval = sysfs_create_group(hstate_kobjs[hi],
>> + &hstate_demote_attr_group);
> What about add one more:
> just return if hstate_attr_group creating failed:
>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 0aee2f3ae15c..a67ef4b4eb3f 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -3845,6 +3845,7 @@ static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent,
> if (retval) {
> kobject_put(hstate_kobjs[hi]);
> hstate_kobjs[hi] = NULL;
> + return retval;
> }
Please ignore this. Just saw the patch 2 made this change.
Regards
Yin, Fengwei
>
> Once hstate_kobjs[hi] is set to NULL, hstate_demote_attr_group creating will
> fail as well. Thanks.
>
>
> Regards
> Yin, Fengwei
>
>> + if (retval) {
>> pr_warn("HugeTLB unable to create demote interfaces for %s\n", h->name);
>> + sysfs_remove_group(hstate_kobjs[hi], hstate_attr_group);
>> + kobject_put(hstate_kobjs[hi]);
>> + hstate_kobjs[hi] = NULL;
>> + return retval;
>> + }
>> }
>
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