[PATCH 3.16 256/370] SUNRPC: cleanup ida information when removing sunrpc module

[Ben Hutchings]

3.16.42-rc1 review patch.  If anyone has any objections, please let me know.

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

From: Kinglong Mee <kinglongmee@xxxxxxxxx>

commit c929ea0b910355e1876c64431f3d5802f95b3d75 upstream.

After removing sunrpc module, I get many kmemleak information as,
unreferenced object 0xffff88003316b1e0 (size 544):
  comm "gssproxy", pid 2148, jiffies 4294794465 (age 4200.081s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffffb0cfb58a>] kmemleak_alloc+0x4a/0xa0
    [<ffffffffb03507fe>] kmem_cache_alloc+0x15e/0x1f0
    [<ffffffffb0639baa>] ida_pre_get+0xaa/0x150
    [<ffffffffb0639cfd>] ida_simple_get+0xad/0x180
    [<ffffffffc06054fb>] nlmsvc_lookup_host+0x4ab/0x7f0 [lockd]
    [<ffffffffc0605e1d>] lockd+0x4d/0x270 [lockd]
    [<ffffffffc06061e5>] param_set_timeout+0x55/0x100 [lockd]
    [<ffffffffc06cba24>] svc_defer+0x114/0x3f0 [sunrpc]
    [<ffffffffc06cbbe7>] svc_defer+0x2d7/0x3f0 [sunrpc]
    [<ffffffffc06c71da>] rpc_show_info+0x8a/0x110 [sunrpc]
    [<ffffffffb044a33f>] proc_reg_write+0x7f/0xc0
    [<ffffffffb038e41f>] __vfs_write+0xdf/0x3c0
    [<ffffffffb0390f1f>] vfs_write+0xef/0x240
    [<ffffffffb0392fbd>] SyS_write+0xad/0x130
    [<ffffffffb0d06c37>] entry_SYSCALL_64_fastpath+0x1a/0xa9
    [<ffffffffffffffff>] 0xffffffffffffffff

I found, the ida information (dynamic memory) isn't cleanup.

Signed-off-by: Kinglong Mee <kinglongmee@xxxxxxxxx>
Fixes: 2f048db4680a ("SUNRPC: Add an identifier for struct rpc_clnt")
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 include/linux/sunrpc/clnt.h | 1 +
 net/sunrpc/clnt.c           | 5 +++++
 net/sunrpc/sunrpc_syms.c    | 1 +
 3 files changed, 7 insertions(+)

--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -175,6 +175,7 @@ void		rpc_force_rebind(struct rpc_clnt *
 size_t		rpc_peeraddr(struct rpc_clnt *, struct sockaddr *, size_t);
 const char	*rpc_peeraddr2str(struct rpc_clnt *, enum rpc_display_format_t);
 int		rpc_localaddr(struct rpc_clnt *, struct sockaddr *, size_t);
+void rpc_cleanup_clids(void);
 
 #endif /* __KERNEL__ */
 #endif /* _LINUX_SUNRPC_CLNT_H */
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -336,6 +336,11 @@ out:
 
 static DEFINE_IDA(rpc_clids);
 
+void rpc_cleanup_clids(void)
+{
+	ida_destroy(&rpc_clids);
+}
+
 static int rpc_alloc_clid(struct rpc_clnt *clnt)
 {
 	int clid;
--- a/net/sunrpc/sunrpc_syms.c
+++ b/net/sunrpc/sunrpc_syms.c
@@ -117,6 +117,7 @@ out:
 static void __exit
 cleanup_sunrpc(void)
 {
+	rpc_cleanup_clids();
 	rpcauth_remove_module();
 	cleanup_socket_xprt();
 	svc_cleanup_xprt_sock();