2023-03-29 13:11:21

by Sricharan Ramabadhran

[permalink] [raw]
Subject: [PATCH] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT

When the qrtr socket is released, qrtr_port_remove gets called, which
broadcasts a DEL_CLIENT. After this DEL_SERVER is also additionally
broadcasted, which becomes NOP, but triggers the below error msg.

"failed while handling packet from 2:-2", since remote node already
acted upon on receiving the DEL_CLIENT, once again when it receives
the DEL_SERVER, it returns -ENOENT.

Fixing it by not sending a 'DEL_SERVER' to remote when a 'DEL_CLIENT'
was sent for that port.

Signed-off-by: Ram Kumar D <[email protected]>
Signed-off-by: Sricharan R <[email protected]>
---
Note: Functionally tested on 5.4 kernel and compile tested on 6.3 TOT

net/qrtr/ns.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
index 722936f..6fbb195 100644
--- a/net/qrtr/ns.c
+++ b/net/qrtr/ns.c
@@ -274,7 +274,7 @@ static struct qrtr_server *server_add(unsigned int service,
return NULL;
}

-static int server_del(struct qrtr_node *node, unsigned int port)
+static int server_del(struct qrtr_node *node, unsigned int port, bool del_server)
{
struct qrtr_lookup *lookup;
struct qrtr_server *srv;
@@ -287,7 +287,7 @@ static int server_del(struct qrtr_node *node, unsigned int port)
radix_tree_delete(&node->servers, port);

/* Broadcast the removal of local servers */
- if (srv->node == qrtr_ns.local_node)
+ if (srv->node == qrtr_ns.local_node && del_server)
service_announce_del(&qrtr_ns.bcast_sq, srv);

/* Announce the service's disappearance to observers */
@@ -373,7 +373,7 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from)
}
slot = radix_tree_iter_resume(slot, &iter);
rcu_read_unlock();
- server_del(node, srv->port);
+ server_del(node, srv->port, true);
rcu_read_lock();
}
rcu_read_unlock();
@@ -459,10 +459,14 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from,
kfree(lookup);
}

- /* Remove the server belonging to this port */
+ /* Remove the server belonging to this port
+ * Given that DEL_CLIENT is already broadcasted
+ * by port_remove, no need to send DEL_SERVER for
+ * the same port to remote
+ */
node = node_get(node_id);
if (node)
- server_del(node, port);
+ server_del(node, port, false);

/* Advertise the removal of this client to all local servers */
local_node = node_get(qrtr_ns.local_node);
@@ -567,7 +571,7 @@ static int ctrl_cmd_del_server(struct sockaddr_qrtr *from,
if (!node)
return -ENOENT;

- return server_del(node, port);
+ return server_del(node, port, true);
}

static int ctrl_cmd_new_lookup(struct sockaddr_qrtr *from,
--
2.7.4


2023-03-30 04:41:18

by Jakub Kicinski

[permalink] [raw]
Subject: Re: [PATCH] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT

On Wed, 29 Mar 2023 18:37:30 +0530 Sricharan R wrote:
> When the qrtr socket is released, qrtr_port_remove gets called, which
> broadcasts a DEL_CLIENT. After this DEL_SERVER is also additionally
> broadcasted, which becomes NOP, but triggers the below error msg.
>
> "failed while handling packet from 2:-2", since remote node already
> acted upon on receiving the DEL_CLIENT, once again when it receives
> the DEL_SERVER, it returns -ENOENT.
>
> Fixing it by not sending a 'DEL_SERVER' to remote when a 'DEL_CLIENT'
> was sent for that port.

You use the word "fix" so please add a Fixes tag.

> Signed-off-by: Ram Kumar D <[email protected]>
> Signed-off-by: Sricharan R <[email protected]>

Spell out full names, please.

2023-03-30 06:32:01

by Manivannan Sadhasivam

[permalink] [raw]
Subject: Re: [PATCH] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT

On Wed, Mar 29, 2023 at 06:37:30PM +0530, Sricharan R wrote:
> When the qrtr socket is released, qrtr_port_remove gets called, which
> broadcasts a DEL_CLIENT. After this DEL_SERVER is also additionally
> broadcasted, which becomes NOP, but triggers the below error msg.
>
> "failed while handling packet from 2:-2", since remote node already
> acted upon on receiving the DEL_CLIENT, once again when it receives
> the DEL_SERVER, it returns -ENOENT.
>
> Fixing it by not sending a 'DEL_SERVER' to remote when a 'DEL_CLIENT'
> was sent for that port.
>

Can you share the qrtr trace when this happens to help me understand the flow?

- Mani

> Signed-off-by: Ram Kumar D <[email protected]>
> Signed-off-by: Sricharan R <[email protected]>
> ---
> Note: Functionally tested on 5.4 kernel and compile tested on 6.3 TOT
>
> net/qrtr/ns.c | 16 ++++++++++------
> 1 file changed, 10 insertions(+), 6 deletions(-)
>
> diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
> index 722936f..6fbb195 100644
> --- a/net/qrtr/ns.c
> +++ b/net/qrtr/ns.c
> @@ -274,7 +274,7 @@ static struct qrtr_server *server_add(unsigned int service,
> return NULL;
> }
>
> -static int server_del(struct qrtr_node *node, unsigned int port)
> +static int server_del(struct qrtr_node *node, unsigned int port, bool del_server)
> {
> struct qrtr_lookup *lookup;
> struct qrtr_server *srv;
> @@ -287,7 +287,7 @@ static int server_del(struct qrtr_node *node, unsigned int port)
> radix_tree_delete(&node->servers, port);
>
> /* Broadcast the removal of local servers */
> - if (srv->node == qrtr_ns.local_node)
> + if (srv->node == qrtr_ns.local_node && del_server)
> service_announce_del(&qrtr_ns.bcast_sq, srv);
>
> /* Announce the service's disappearance to observers */
> @@ -373,7 +373,7 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from)
> }
> slot = radix_tree_iter_resume(slot, &iter);
> rcu_read_unlock();
> - server_del(node, srv->port);
> + server_del(node, srv->port, true);
> rcu_read_lock();
> }
> rcu_read_unlock();
> @@ -459,10 +459,14 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from,
> kfree(lookup);
> }
>
> - /* Remove the server belonging to this port */
> + /* Remove the server belonging to this port
> + * Given that DEL_CLIENT is already broadcasted
> + * by port_remove, no need to send DEL_SERVER for
> + * the same port to remote
> + */
> node = node_get(node_id);
> if (node)
> - server_del(node, port);
> + server_del(node, port, false);
>
> /* Advertise the removal of this client to all local servers */
> local_node = node_get(qrtr_ns.local_node);
> @@ -567,7 +571,7 @@ static int ctrl_cmd_del_server(struct sockaddr_qrtr *from,
> if (!node)
> return -ENOENT;
>
> - return server_del(node, port);
> + return server_del(node, port, true);
> }
>
> static int ctrl_cmd_new_lookup(struct sockaddr_qrtr *from,
> --
> 2.7.4
>

--
மணிவண்ணன் சதாசிவம்

2023-03-30 09:52:21

by Sricharan Ramabadhran

[permalink] [raw]
Subject: Re: [PATCH] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT



On 3/30/2023 11:54 AM, Manivannan Sadhasivam wrote:
> On Wed, Mar 29, 2023 at 06:37:30PM +0530, Sricharan R wrote:
>> When the qrtr socket is released, qrtr_port_remove gets called, which
>> broadcasts a DEL_CLIENT. After this DEL_SERVER is also additionally
>> broadcasted, which becomes NOP, but triggers the below error msg.
>>
>> "failed while handling packet from 2:-2", since remote node already
>> acted upon on receiving the DEL_CLIENT, once again when it receives
>> the DEL_SERVER, it returns -ENOENT.
>>
>> Fixing it by not sending a 'DEL_SERVER' to remote when a 'DEL_CLIENT'
>> was sent for that port.
>>
>
> Can you share the qrtr trace when this happens to help me understand the flow?

Flow is like this.

IPQ SDX
--- ----
qrtr_release
qrtr_port_remove
qrtr_send_del_client
|
|
|
|
RX CTRL: cmd:0x6 addr[0x2:0x40d4]<-----------|
(qrtr_send_client broadcasts it to |
the remote, |
IPQ cleans up the port) |
|
ctrl_cmd_del_client
(send_del_client
also forwards the
DEL_CLIENT to
internal ns.c.
Which then again
sends DEL_server
to same port to
remote)
|
|
RX CTRL: cmd:0x5 SVC[0x1389:0x1] |
addr[0x2:0x40d4] <-------------------- ---|
(IPQ on receiving the DEL_SERVER on
same port throws the message
"failed while handling packet from 2:-2")


Regards,
Sricharan

2023-03-30 10:00:19

by Sricharan Ramabadhran

[permalink] [raw]
Subject: Re: [PATCH] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT



On 3/30/2023 10:02 AM, Jakub Kicinski wrote:
> On Wed, 29 Mar 2023 18:37:30 +0530 Sricharan R wrote:
>> When the qrtr socket is released, qrtr_port_remove gets called, which
>> broadcasts a DEL_CLIENT. After this DEL_SERVER is also additionally
>> broadcasted, which becomes NOP, but triggers the below error msg.
>>
>> "failed while handling packet from 2:-2", since remote node already
>> acted upon on receiving the DEL_CLIENT, once again when it receives
>> the DEL_SERVER, it returns -ENOENT.
>>
>> Fixing it by not sending a 'DEL_SERVER' to remote when a 'DEL_CLIENT'
>> was sent for that port.
>
> You use the word "fix" so please add a Fixes tag.
>

ok

>> Signed-off-by: Ram Kumar D <[email protected]>
>> Signed-off-by: Sricharan R <[email protected]>
>
> Spell out full names, please.

ok

Regards,
Sricharan

2023-03-30 12:42:07

by Manivannan Sadhasivam

[permalink] [raw]
Subject: Re: [PATCH] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT

On Wed, Mar 29, 2023 at 06:37:30PM +0530, Sricharan R wrote:
> When the qrtr socket is released, qrtr_port_remove gets called, which
> broadcasts a DEL_CLIENT. After this DEL_SERVER is also additionally
> broadcasted, which becomes NOP, but triggers the below error msg.
>
> "failed while handling packet from 2:-2", since remote node already
> acted upon on receiving the DEL_CLIENT, once again when it receives
> the DEL_SERVER, it returns -ENOENT.
>
> Fixing it by not sending a 'DEL_SERVER' to remote when a 'DEL_CLIENT'
> was sent for that port.
>

How about:

"On the remote side, when QRTR socket is removed, af_qrtr will call
qrtr_port_remove() which broadcasts the DEL_CLIENT packet to all neighbours
including local NS. NS upon receiving the DEL_CLIENT packet, will remove
the lookups associated with the node:port and broadcasts the DEL_SERVER
packet.

But on the host side, due to the arrival of the DEL_CLIENT packet, the NS
would've already deleted the server belonging to that port. So when the
remote's NS again broadcasts the DEL_SERVER for that port, it throws below
error message on the host:

"failed while handling packet from 2:-2"

So fix this error by not broadcasting the DEL_SERVER packet when the
DEL_CLIENT packet gets processed."

> Signed-off-by: Ram Kumar D <[email protected]>
> Signed-off-by: Sricharan R <[email protected]>
> ---
> Note: Functionally tested on 5.4 kernel and compile tested on 6.3 TOT
>
> net/qrtr/ns.c | 16 ++++++++++------
> 1 file changed, 10 insertions(+), 6 deletions(-)
>
> diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
> index 722936f..6fbb195 100644
> --- a/net/qrtr/ns.c
> +++ b/net/qrtr/ns.c
> @@ -274,7 +274,7 @@ static struct qrtr_server *server_add(unsigned int service,
> return NULL;
> }
>
> -static int server_del(struct qrtr_node *node, unsigned int port)
> +static int server_del(struct qrtr_node *node, unsigned int port, bool del_server)

s/bool del_server/bool bcast/g

> {
> struct qrtr_lookup *lookup;
> struct qrtr_server *srv;
> @@ -287,7 +287,7 @@ static int server_del(struct qrtr_node *node, unsigned int port)
> radix_tree_delete(&node->servers, port);
>
> /* Broadcast the removal of local servers */
> - if (srv->node == qrtr_ns.local_node)
> + if (srv->node == qrtr_ns.local_node && del_server)
> service_announce_del(&qrtr_ns.bcast_sq, srv);
>
> /* Announce the service's disappearance to observers */
> @@ -373,7 +373,7 @@ static int ctrl_cmd_bye(struct sockaddr_qrtr *from)
> }
> slot = radix_tree_iter_resume(slot, &iter);
> rcu_read_unlock();
> - server_del(node, srv->port);
> + server_del(node, srv->port, true);
> rcu_read_lock();
> }
> rcu_read_unlock();
> @@ -459,10 +459,14 @@ static int ctrl_cmd_del_client(struct sockaddr_qrtr *from,
> kfree(lookup);
> }
>
> - /* Remove the server belonging to this port */
> + /* Remove the server belonging to this port
> + * Given that DEL_CLIENT is already broadcasted
> + * by port_remove, no need to send DEL_SERVER for
> + * the same port to remote
> + */

/*
* Remove the server belonging to this port but don't broadcast
* DEL_SERVER. Neighbours would've already removed the server belonging
* to this port due to the DEL_CLIENT broadcast from qrtr_port_remove().
*/
- Mani

> node = node_get(node_id);
> if (node)
> - server_del(node, port);
> + server_del(node, port, false);
>
> /* Advertise the removal of this client to all local servers */
> local_node = node_get(qrtr_ns.local_node);
> @@ -567,7 +571,7 @@ static int ctrl_cmd_del_server(struct sockaddr_qrtr *from,
> if (!node)
> return -ENOENT;
>
> - return server_del(node, port);
> + return server_del(node, port, true);
> }
>
> static int ctrl_cmd_new_lookup(struct sockaddr_qrtr *from,
> --
> 2.7.4
>

--
மணிவண்ணன் சதாசிவம்

2023-03-30 19:48:58

by Sricharan Ramabadhran

[permalink] [raw]
Subject: Re: [PATCH] net: qrtr: Do not do DEL_SERVER broadcast after DEL_CLIENT



On 3/30/2023 6:09 PM, Manivannan Sadhasivam wrote:
> On Wed, Mar 29, 2023 at 06:37:30PM +0530, Sricharan R wrote:
>> When the qrtr socket is released, qrtr_port_remove gets called, which
>> broadcasts a DEL_CLIENT. After this DEL_SERVER is also additionally
>> broadcasted, which becomes NOP, but triggers the below error msg.
>>
>> "failed while handling packet from 2:-2", since remote node already
>> acted upon on receiving the DEL_CLIENT, once again when it receives
>> the DEL_SERVER, it returns -ENOENT.
>>
>> Fixing it by not sending a 'DEL_SERVER' to remote when a 'DEL_CLIENT'
>> was sent for that port.
>>
>
> How about:
>
> "On the remote side, when QRTR socket is removed, af_qrtr will call
> qrtr_port_remove() which broadcasts the DEL_CLIENT packet to all neighbours
> including local NS. NS upon receiving the DEL_CLIENT packet, will remove
> the lookups associated with the node:port and broadcasts the DEL_SERVER
> packet.
>
> But on the host side, due to the arrival of the DEL_CLIENT packet, the NS
> would've already deleted the server belonging to that port. So when the
> remote's NS again broadcasts the DEL_SERVER for that port, it throws below
> error message on the host:
>
> "failed while handling packet from 2:-2"
>
> So fix this error by not broadcasting the DEL_SERVER packet when the
> DEL_CLIENT packet gets processed."
>

Sure, sounds good. Will change this up and send V2.

>> Signed-off-by: Ram Kumar D <[email protected]>
>> Signed-off-by: Sricharan R <[email protected]>
>> ---
>> Note: Functionally tested on 5.4 kernel and compile tested on 6.3 TOT
>>

<...>

>>
>> - /* Remove the server belonging to this port */
>> + /* Remove the server belonging to this port
>> + * Given that DEL_CLIENT is already broadcasted
>> + * by port_remove, no need to send DEL_SERVER for
>> + * the same port to remote
>> + */
>
> /*
> * Remove the server belonging to this port but don't broadcast
> * DEL_SERVER. Neighbours would've already removed the server belonging
> * to this port due to the DEL_CLIENT broadcast from qrtr_port_remove().
> */

Sure, would reword it like above in V2. Thanks.

Regards,
Sricharan