parisc: mm: Fix a memory leak related to pmd not attached to the pgd

Commit 0e0da48dee ("parisc: mm: don't count preallocated pmds")
introduced a memory leak.

After this commit, the 'return' statement in pmd_free is executed in all
cases. Even for pmd that are not attached to the pgd.  So 'free_pages'
can never be called anymore, leading to a memory leak.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org  # v4.0+
Signed-off-by: Helge Deller <deller@gmx.de>
This commit is contained in:
Christophe Jaillet 2015-07-13 11:32:43 +02:00 committed by Helge Deller
parent 9d37e6679d
commit 4c4ac9a48a

View File

@ -72,7 +72,7 @@ static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
{
if(pmd_flag(*pmd) & PxD_FLAG_ATTACHED)
if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED) {
/*
* This is the permanent pmd attached to the pgd;
* cannot free it.
@ -81,6 +81,7 @@ static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
*/
mm_inc_nr_pmds(mm);
return;
}
free_pages((unsigned long)pmd, PMD_ORDER);
}