From: Trond Myklebust trond.myklebust@primarydata.com
[ Upstream commit 0afa6b4412988019db14c6bfb8c6cbdf120ca9ad ]
Calling __UDPX_INC_STATS() from a preemptible context leads to a warning of the form:
BUG: using __this_cpu_add() in preemptible [00000000] code: kworker/u5:0/31 caller is xs_udp_data_receive_workfn+0x194/0x270 CPU: 1 PID: 31 Comm: kworker/u5:0 Not tainted 4.15.0-rc8-00076-g90ea9f1 #2 Workqueue: xprtiod xs_udp_data_receive_workfn Call Trace: dump_stack+0x85/0xc1 check_preemption_disabled+0xce/0xe0 xs_udp_data_receive_workfn+0x194/0x270 process_one_work+0x318/0x620 worker_thread+0x20a/0x390 ? process_one_work+0x620/0x620 kthread+0x120/0x130 ? __kthread_bind_mask+0x60/0x60 ret_from_fork+0x24/0x30
Since we're taking a spinlock in those functions anyway, let's fix the issue by moving the call so that it occurs under the spinlock.
Reported-by: kernel test robot fengguang.wu@intel.com Signed-off-by: Trond Myklebust trond.myklebust@primarydata.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com --- net/sunrpc/xprtsock.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c index 6d0cc3b8f932..33e2baebdca7 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -1070,18 +1070,18 @@ static void xs_udp_data_read_skb(struct rpc_xprt *xprt,
/* Suck it into the iovec, verify checksum if not done by hw. */ if (csum_partial_copy_to_xdr(&rovr->rq_private_buf, skb)) { - __UDPX_INC_STATS(sk, UDP_MIB_INERRORS); spin_lock(&xprt->recv_lock); + __UDPX_INC_STATS(sk, UDP_MIB_INERRORS); goto out_unpin; }
- __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS);
spin_lock_bh(&xprt->transport_lock); xprt_adjust_cwnd(xprt, task, copied); spin_unlock_bh(&xprt->transport_lock); spin_lock(&xprt->recv_lock); xprt_complete_rqst(task, copied); + __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS); out_unpin: xprt_unpin_rqst(rovr); out_unlock: