On Wed, Apr 20, 2022 at 2:41 PM Trond Myklebust <[email protected]> wrote:
>
> On Wed, 2022-04-20 at 14:21 -0400, Olga Kornievskaia wrote:
> > From: Olga Kornievskaia <[email protected]>
> >
> > A relocated task must release its previous transport.
> >
> > Fixes: 82ee41b85cef1 ("SUNRPC don't resend a task on an offlined
> > transport")
> > Signed-off-by: Olga Kornievskaia <[email protected]>
> > ---
> > net/sunrpc/clnt.c | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
> > index af0174d7ce5a..95de454a858b 100644
> > --- a/net/sunrpc/clnt.c
> > +++ b/net/sunrpc/clnt.c
> > @@ -1067,8 +1067,10 @@ void rpc_task_set_transport(struct rpc_task
> > *task, struct rpc_clnt *clnt)
> > {
> > if (task->tk_xprt &&
> > !(test_bit(XPRT_OFFLINE, &task->tk_xprt-
> > >state) &&
> > - (task->tk_flags & RPC_TASK_MOVEABLE)))
> > + (task->tk_flags & RPC_TASK_MOVEABLE))) {
> > + xprt_release_write(task->tk_xprt, task);
> > return;
> > + }
> > if (task->tk_flags & RPC_TASK_NO_ROUND_ROBIN)
> > task->tk_xprt = rpc_task_get_first_xprt(clnt);
> > else
>
>
> I don't think this patch is correct. It is changing the case where
> we're not changing the value of task->tk_xprt, which was never a
> problem before commit 82ee41b85cef.
>
> What needs to change is the case where task->tk_xprt is set, but we're
> going to change its value anyway because of the tests for XPRT_OFFLINE
> and RPC_TASK_MOVEABLE.
> In that case we need to call xprt_release(), followed by xprt_put().
> Otherwise we're leaking slots, locks and references to the old task-
> >tk_xprt.
Thank you Trond. It is indeed incorrect. I've sent v2.
>
> --
> Trond Myklebust
> Linux NFS client maintainer, Hammerspace
> [email protected]
>
>