From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steve French Subject: Re: [PATCH v4] cifs: Do not modify mid entry after submitting I/O in cifs_call_async Date: Thu, 29 Jun 2017 10:56:08 -0500 Message-ID: References: <1498690555-8454-1-git-send-email-longli@exchange.microsoft.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Cc: Steve French , "linux-cifs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , samba-technical , LKML , Long Li To: Long Li Return-path: In-Reply-To: <1498690555-8454-1-git-send-email-longli-Lp/cVzEoVyZiJJESP9tAQJZ3qXmFLfmx@public.gmane.org> Sender: linux-cifs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: merged into cifs-2.6.git for-next On Wed, Jun 28, 2017 at 5:55 PM, Long Li wrote: > 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 > Reviewed-by: Pavel Shilovsky > --- > fs/cifs/transport.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c > index 47a125e..7efbab0 100644 > --- a/fs/cifs/transport.c > +++ b/fs/cifs/transport.c > @@ -536,11 +536,14 @@ 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 may 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 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-cifs" in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Thanks, Steve From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752770AbdF2P4i (ORCPT ); Thu, 29 Jun 2017 11:56:38 -0400 Received: from mail-pg0-f65.google.com ([74.125.83.65]:36238 "EHLO mail-pg0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751783AbdF2P43 (ORCPT ); Thu, 29 Jun 2017 11:56:29 -0400 MIME-Version: 1.0 In-Reply-To: <1498690555-8454-1-git-send-email-longli@exchange.microsoft.com> References: <1498690555-8454-1-git-send-email-longli@exchange.microsoft.com> From: Steve French Date: Thu, 29 Jun 2017 10:56:08 -0500 Message-ID: Subject: Re: [PATCH v4] cifs: Do not modify mid entry after submitting I/O in cifs_call_async To: Long Li Cc: Steve French , "linux-cifs@vger.kernel.org" , samba-technical , LKML , Long Li Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org merged into cifs-2.6.git for-next On Wed, Jun 28, 2017 at 5:55 PM, Long Li wrote: > 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 > Reviewed-by: Pavel Shilovsky > --- > fs/cifs/transport.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c > index 47a125e..7efbab0 100644 > --- a/fs/cifs/transport.c > +++ b/fs/cifs/transport.c > @@ -536,11 +536,14 @@ 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 may 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 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-cifs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Thanks, Steve