| From | Greg Kroah-Hartman <> | Subject | [PATCH 4.1 006/123] parisc: mm: Fix a memory leak related to pmd not attached to the pgd | Date | Sat, 8 Aug 2015 15:08:04 -0700 |
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4.1-stable review patch. If anyone has any objections, please let me know.
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From: Christophe Jaillet <christophe.jaillet@wanadoo.fr>
commit 4c4ac9a48ac512c6b5a6cca06cfad2ad96e8caaa upstream.
Commit 0e0da48dee8d ("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> Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- arch/parisc/include/asm/pgalloc.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/arch/parisc/include/asm/pgalloc.h +++ b/arch/parisc/include/asm/pgalloc.h @@ -72,7 +72,7 @@ static inline pmd_t *pmd_alloc_one(struc 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_st */ mm_inc_nr_pmds(mm); return; + } free_pages((unsigned long)pmd, PMD_ORDER); }
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