Commit e5d96a31 authored by Liu Shixin's avatar Liu Shixin
Browse files

mm/dynamic_hugetlb: replace spin_lock with mutex_lock and fix kabi broken 

hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6MH03


CVE: NA

--------------------------------

When memory is fragmented, update_reserve_pages() may call migrate_pages()
to collect continuous memory. This function can sleep, so we should use
mutex lock instead of spin lock. Use KABI_EXTEND to fix kabi broken.

Fixes: 0c06a1c0 ("mm/dynamic_hugetlb: add interface to configure the count of hugepages")
Signed-off-by: default avatarLiu Shixin <liushixin2@huawei.com>
parent 2430060b

include/linux/dynamic_hugetlb.h

+13 −1
Original line number Diff line number Diff line
@@ -66,7 +66,7 @@ enum huge_pages_pool_type { 
struct dhugetlb_pool {

	int nid;

	spinlock_t lock;

	spinlock_t reserved_lock;

	KABI_DEPRECATE(spinlock_t, reserved_lock)

	atomic_t refcnt;

	unsigned long normal_pages_disabled;
@@ -74,6 +74,18 @@ struct dhugetlb_pool { 


	unsigned long total_huge_pages;

	struct huge_pages_pool hpages_pool[HUGE_PAGES_POOL_MAX];



	/* The dhugetlb_pool structures is only used by core kernel, it is

	 * also accessed only the memory cgroup and hugetlb core code and

	 * so changes made to dhugetlb_pool structure should not affect

	 * third-party kernel modules.

	 */

	KABI_EXTEND(struct mutex reserved_lock)



	/*

	 * The percpu_pool[] should only be used by dynamic hugetlb core.

	 * External kernel modules should not used it.

	 */

	struct percpu_pages_pool percpu_pool[0];

};

mm/dynamic_hugetlb.c

+3 −3
Original line number Diff line number Diff line
@@ -887,7 +887,7 @@ static int hugetlb_pool_create(struct mem_cgroup *memcg, unsigned long nid) 
		return -ENOMEM;



	spin_lock_init(&hpool->lock);

	spin_lock_init(&hpool->reserved_lock);

	mutex_init(&hpool->reserved_lock);

	hpool->nid = nid;

	atomic_set(&hpool->refcnt, 1);
@@ -1000,7 +1000,7 @@ static ssize_t update_reserved_pages(struct mem_cgroup *memcg, char *buf, int hp 
	if (!get_hpool_unless_zero(hpool))

		return -EINVAL;



	spin_lock(&hpool->reserved_lock);

	mutex_lock(&hpool->reserved_lock);

	spin_lock(&hpool->lock);

	hpages_pool = &hpool->hpages_pool[hpages_pool_idx];

	if (nr_pages > hpages_pool->nr_huge_pages) {
@@ -1036,7 +1036,7 @@ static ssize_t update_reserved_pages(struct mem_cgroup *memcg, char *buf, int hp 
		hpages_pool->free_normal_pages += delta;

	}

	spin_unlock(&hpool->lock);

	spin_unlock(&hpool->reserved_lock);

	mutex_unlock(&hpool->reserved_lock);

	put_hpool(hpool);

	return 0;

}