From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-by2nam03on0131.outbound.protection.outlook.com ([104.47.42.131]:4960 "EHLO NAM03-BY2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755311AbeDIA0U (ORCPT ); Sun, 8 Apr 2018 20:26:20 -0400 From: Sasha Levin To: "stable@vger.kernel.org" , "linux-kernel@vger.kernel.org" CC: Trond Myklebust , Sasha Levin Subject: [PATCH AUTOSEL for 4.14 148/161] SUNRPC: Don't call __UDPX_INC_STATS() from a preemptible context Date: Mon, 9 Apr 2018 00:21:54 +0000 Message-ID: <20180409001936.162706-148-alexander.levin@microsoft.com> References: <20180409001936.162706-1-alexander.levin@microsoft.com> In-Reply-To: <20180409001936.162706-1-alexander.levin@microsoft.com> Content-Language: en-US Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org List-ID: From: Trond Myklebust [ 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/u5:0/3= 1 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 Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin --- 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 8cb40f8ffa5b..30192abfdc3b 100644 --- a/net/sunrpc/xprtsock.c +++ b/net/sunrpc/xprtsock.c @@ -1069,18 +1069,18 @@ static void xs_udp_data_read_skb(struct rpc_xprt *x= prt, =20 /* 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; } =20 - __UDPX_INC_STATS(sk, UDP_MIB_INDATAGRAMS); =20 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: --=20 2.15.1