diff mbox series

rpmsg: glink: Avoid infinite loop on intent for missing channel

Message ID 20230109223801.1706213-1-quic_bjorande@quicinc.com
State New
Headers
Series rpmsg: glink: Avoid infinite loop on intent for missing channel |

Commit Message

Bjorn Andersson Jan. 9, 2023, 10:38 p.m. UTC 
  In the event that an intent advertisement arrives on an unknown channel
the fifo is not advanced, resulting in the same message being handled
over and over.

Fixes: dacbb35e930f ("rpmsg: glink: Receive and store the remote intent buffers")
Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
---
 drivers/rpmsg/qcom_glink_native.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

Comments

Chris Lew Feb. 14, 2023, 10:55 p.m. UTC | #1 
On 1/9/2023 2:38 PM, Bjorn Andersson wrote:
> In the event that an intent advertisement arrives on an unknown channel
> the fifo is not advanced, resulting in the same message being handled
> over and over.
> 
> Fixes: dacbb35e930f ("rpmsg: glink: Receive and store the remote intent buffers")
> Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
> ---
>   drivers/rpmsg/qcom_glink_native.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
> index f36740cb6866..7b1320b1579e 100644
> --- a/drivers/rpmsg/qcom_glink_native.c
> +++ b/drivers/rpmsg/qcom_glink_native.c
> @@ -946,12 +946,12 @@ static void qcom_glink_handle_intent(struct qcom_glink *glink,
>   	spin_unlock_irqrestore(&glink->idr_lock, flags);
>   	if (!channel) {
>   		dev_err(glink->dev, "intents for non-existing channel\n");
> -		return;
> +		goto advance_rx;
>   	}
>   
>   	msg = kmalloc(msglen, GFP_ATOMIC);
>   	if (!msg)
> -		return;
> +		goto advance_rx;


Should we be dropping the packet for this case? If we try again later 
more memory might be available to handle the command.

>   
>   	qcom_glink_rx_peak(glink, msg, 0, msglen);
>   
> @@ -973,6 +973,7 @@ static void qcom_glink_handle_intent(struct qcom_glink *glink,
>   	}
>   
>   	kfree(msg);
> +advance_rx:
>   	qcom_glink_rx_advance(glink, ALIGN(msglen, 8));
>   }
>   
>
Bjorn Andersson Feb. 14, 2023, 11:34 p.m. UTC | #2 
On Tue, Feb 14, 2023 at 02:55:02PM -0800, Chris Lew wrote:
> On 1/9/2023 2:38 PM, Bjorn Andersson wrote:
> > In the event that an intent advertisement arrives on an unknown channel
> > the fifo is not advanced, resulting in the same message being handled
> > over and over.
> > 
> > Fixes: dacbb35e930f ("rpmsg: glink: Receive and store the remote intent buffers")
> > Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
> > ---
> >   drivers/rpmsg/qcom_glink_native.c | 5 +++--
> >   1 file changed, 3 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
> > index f36740cb6866..7b1320b1579e 100644
> > --- a/drivers/rpmsg/qcom_glink_native.c
> > +++ b/drivers/rpmsg/qcom_glink_native.c
> > @@ -946,12 +946,12 @@ static void qcom_glink_handle_intent(struct qcom_glink *glink,
> >   	spin_unlock_irqrestore(&glink->idr_lock, flags);
> >   	if (!channel) {
> >   		dev_err(glink->dev, "intents for non-existing channel\n");
> > -		return;
> > +		goto advance_rx;
> >   	}
> >   	msg = kmalloc(msglen, GFP_ATOMIC);
> >   	if (!msg)
> > -		return;
> > +		goto advance_rx;
> 
> 
> Should we be dropping the packet for this case? If we try again later more
> memory might be available to handle the command.
> 

You're right, we found a channel above, but we don't have enough memory
to handle the message right now. That seems like a message worth not
throwing away.

Thanks,
Bjorn

> >   	qcom_glink_rx_peak(glink, msg, 0, msglen);
> > @@ -973,6 +973,7 @@ static void qcom_glink_handle_intent(struct qcom_glink *glink,
> >   	}
> >   	kfree(msg);
> > +advance_rx:
> >   	qcom_glink_rx_advance(glink, ALIGN(msglen, 8));
> >   }
> >
diff mbox series

Patch

diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
index f36740cb6866..7b1320b1579e 100644
--- a/drivers/rpmsg/qcom_glink_native.c
+++ b/drivers/rpmsg/qcom_glink_native.c
@@ -946,12 +946,12 @@  static void qcom_glink_handle_intent(struct qcom_glink *glink,
 	spin_unlock_irqrestore(&glink->idr_lock, flags);
 	if (!channel) {
 		dev_err(glink->dev, "intents for non-existing channel\n");
-		return;
+		goto advance_rx;
 	}
 
 	msg = kmalloc(msglen, GFP_ATOMIC);
 	if (!msg)
-		return;
+		goto advance_rx;
 
 	qcom_glink_rx_peak(glink, msg, 0, msglen);
 
@@ -973,6 +973,7 @@  static void qcom_glink_handle_intent(struct qcom_glink *glink,
 	}
 
 	kfree(msg);
+advance_rx:
 	qcom_glink_rx_advance(glink, ALIGN(msglen, 8));
 }