From b836aec53e2bce71de1d5415313380688c851477 Mon Sep 17 00:00:00 2001 From: Bob Liu Date: Thu, 14 Apr 2011 15:22:20 -0700 Subject: [PATCH] ramfs: fix memleak on no-mmu arch On no-mmu arch, there is a memleak during shmem test. The cause of this memleak is ramfs_nommu_expand_for_mapping() added page refcount to 2 which makes iput() can't free that pages. The simple test file is like this: int main(void) { int i; key_t k = ftok("/etc", 42); for ( i=0; i<100; ++i) { int id = shmget(k, 10000, 0644|IPC_CREAT); if (id == -1) { printf("shmget error\n"); } if(shmctl(id, IPC_RMID, NULL ) == -1) { printf("shm rm error\n"); return -1; } } printf("run ok...\n"); return 0; } And the result: root:/> free total used free shared buffers Mem: 60320 17912 42408 0 0 -/+ buffers: 17912 42408 root:/> shmem run ok... root:/> free total used free shared buffers Mem: 60320 19096 41224 0 0 -/+ buffers: 19096 41224 root:/> shmem run ok... root:/> free total used free shared buffers Mem: 60320 20296 40024 0 0 -/+ buffers: 20296 40024 ... After this patch the test result is:(no memleak anymore) root:/> free total used free shared buffers Mem: 60320 16668 43652 0 0 -/+ buffers: 16668 43652 root:/> shmem run ok... root:/> free total used free shared buffers Mem: 60320 16668 43652 0 0 -/+ buffers: 16668 43652 Signed-off-by: Bob Liu Acked-by: Hugh Dickins Signed-off-by: David Howells Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ramfs/file-nommu.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c index 9eead2c796b..fbb0b478a34 100644 --- a/fs/ramfs/file-nommu.c +++ b/fs/ramfs/file-nommu.c @@ -112,6 +112,7 @@ int ramfs_nommu_expand_for_mapping(struct inode *inode, size_t newsize) SetPageDirty(page); unlock_page(page); + put_page(page); } return 0; -- 2.20.1