Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752142AbdF1WEE (ORCPT ); Wed, 28 Jun 2017 18:04:04 -0400 Received: from a2nlsmtp01-02.prod.iad2.secureserver.net ([198.71.225.36]:54300 "EHLO a2nlsmtp01-02.prod.iad2.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752096AbdF1WDt (ORCPT ); Wed, 28 Jun 2017 18:03:49 -0400 x-originating-ip: 107.180.71.197 From: Long Li To: Steve French , linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org Cc: Long Li Subject: [PATCH v3] cifs: Do not modify mid entry after submitting I/O in cifs_call_async Date: Wed, 28 Jun 2017 15:02:38 -0700 Message-Id: <1498687358-7492-1-git-send-email-longli@exchange.microsoft.com> X-Mailer: git-send-email 1.7.1 X-CMAE-Envelope: MS4wfBy7Tplnn1ZN+DnDljz41aLsfq8pVRHAnAUe1d1PoUF9RuuAPZsCwT4bh6jGfPkERYifDUS15L54/sms5kXAOwSxkDfr7ene/3+TNtYQn25yn34l2GG9 w4+4WK4XeXJC2SILR/lV2oJTKnHSgc2uqrCc/Myxv1EIQVLaxa+MTDa5QxAmSWvqCfqGTljjtgpq/3yfmU0J55tCp37fcsYGx5Eqi8NvFSvtlZqg+FJ4TuL5 bzbmQ7Q3DZdmNcdq59Rg9ungMaN2XvpszEweDPz4R4tuHrR3Um8kSOf4iCqsv+5zeGzsFa+QlvnVJqgeRO5JE7fMVmQq8b4RBRUauYPZKDo= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1142 Lines: 36 From: Long Li In cifs_call_async, server may respond as soon as I/O is submitted. Because mid entry is freed on the return path, it should not be modified after I/O is submitted. cifs_save_when_sent modifies the sent timestamp in mid entry, and should not be called after I/O. Call it before I/O. Signed-off-by: Long Li --- fs/cifs/transport.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c index 47a125e..f49b73f 100644 --- a/fs/cifs/transport.c +++ b/fs/cifs/transport.c @@ -536,11 +536,13 @@ cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst, list_add_tail(&mid->qhead, &server->pending_mid_q); spin_unlock(&GlobalMid_Lock); - + /* Need to store the time in mid before calling I/O. For call_async, + * I/O response can come back and free the mid entry on another thread. + */ + cifs_save_when_sent(mid); cifs_in_send_inc(server); rc = smb_send_rqst(server, rqst, flags); cifs_in_send_dec(server); - cifs_save_when_sent(mid); if (rc < 0) { server->sequence_number -= 2; -- 2.7.4