SUNRPC: Fix a backchannel deadlock

xprt_alloc_bc_request() cannot call xprt_free_bc_request() without
deadlocking, since it already holds the xprt->bc_pa_lock.

Reported-by: Chuck Lever <chuck.lever@oracle.com>
Fixes: 0d2a970d0a ("SUNRPC: Fix a backchannel race")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This commit is contained in:
Trond Myklebust 2015-07-22 16:31:17 -04:00
parent faa4a54f0b
commit 68514471ce

View file

@ -240,8 +240,8 @@ static struct rpc_rqst *xprt_alloc_bc_request(struct rpc_xprt *xprt, __be32 xid)
req = xprt_alloc_bc_req(xprt, GFP_ATOMIC);
if (!req)
goto not_found;
/* Note: this 'free' request adds it to xprt->bc_pa_list */
xprt_free_bc_request(req);
list_add_tail(&req->rq_bc_pa_list, &xprt->bc_pa_list);
xprt->bc_alloc_count++;
}
req = list_first_entry(&xprt->bc_pa_list, struct rpc_rqst,
rq_bc_pa_list);