* [PATCH v4] cifs: Do not modify mid entry after submitting I/O in cifs_call_async
@ 2017-06-28 22:55 ` Long Li
0 siblings, 0 replies; 4+ messages in thread
From: Long Li @ 2017-06-28 22:55 UTC (permalink / raw)
To: Steve French, linux-cifs-u79uwXL29TY76Z2rM5mHXA,
samba-technical-w/Ol4Ecudpl8XjKLYN78aQ,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
Cc: Long Li
From: Long Li <longli-0li6OtcxBFHby3iVrkZq2A@public.gmane.org>
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 <longli-0li6OtcxBFHby3iVrkZq2A@public.gmane.org>
Reviewed-by: Pavel Shilovsky <pshilov-0li6OtcxBFHby3iVrkZq2A@public.gmane.org>
---
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
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH v4] cifs: Do not modify mid entry after submitting I/O in cifs_call_async
@ 2017-06-28 22:55 ` Long Li
0 siblings, 0 replies; 4+ messages in thread
From: Long Li @ 2017-06-28 22:55 UTC (permalink / raw)
To: Steve French, linux-cifs, samba-technical, linux-kernel; +Cc: Long Li
From: Long Li <longli@microsoft.com>
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 <longli@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
---
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
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH v4] cifs: Do not modify mid entry after submitting I/O in cifs_call_async
2017-06-28 22:55 ` Long Li
@ 2017-06-29 15:56 ` Steve French
-1 siblings, 0 replies; 4+ messages in thread
From: Steve French @ 2017-06-29 15:56 UTC (permalink / raw)
To: Long Li
Cc: Steve French, linux-cifs-u79uwXL29TY76Z2rM5mHXA, samba-technical,
LKML, Long Li
merged into cifs-2.6.git for-next
On Wed, Jun 28, 2017 at 5:55 PM, Long Li <longli-Lp/cVzEoVyZiJJESP9tAQJZ3qXmFLfmx@public.gmane.org> wrote:
> From: Long Li <longli-0li6OtcxBFHby3iVrkZq2A@public.gmane.org>
>
> 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 <longli-0li6OtcxBFHby3iVrkZq2A@public.gmane.org>
> Reviewed-by: Pavel Shilovsky <pshilov-0li6OtcxBFHby3iVrkZq2A@public.gmane.org>
> ---
> 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
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v4] cifs: Do not modify mid entry after submitting I/O in cifs_call_async
@ 2017-06-29 15:56 ` Steve French
0 siblings, 0 replies; 4+ messages in thread
From: Steve French @ 2017-06-29 15:56 UTC (permalink / raw)
To: Long Li; +Cc: Steve French, linux-cifs, samba-technical, LKML, Long Li
merged into cifs-2.6.git for-next
On Wed, Jun 28, 2017 at 5:55 PM, Long Li <longli@exchange.microsoft.com> wrote:
> From: Long Li <longli@microsoft.com>
>
> 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 <longli@microsoft.com>
> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
> ---
> 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
^ permalink raw reply [flat|nested] 4+ messages in thread
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2017-06-28 22:55 [PATCH v4] cifs: Do not modify mid entry after submitting I/O in cifs_call_async Long Li
2017-06-28 22:55 ` Long Li
[not found] ` <1498690555-8454-1-git-send-email-longli-Lp/cVzEoVyZiJJESP9tAQJZ3qXmFLfmx@public.gmane.org>
2017-06-29 15:56 ` Steve French
2017-06-29 15:56 ` Steve French
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