[PATCH v3 0/2] usb: dwc3: gadget: Fix isoc interrupt check

[PATCH v3 0/2] usb: dwc3: gadget: Fix isoc interrupt check

[Thinh Nguyen]

Fix issues where usb_request->no_interrupt is set for isoc transfers.
* Make sure no interrupt is asserted if no_interrupt is set
* Make sure to stop reclaiming TRBs when the driver needs to stop


Thinh Nguyen (2):
  usb: dwc3: gadget: Stop processing more requests on IMI
  usb: dwc3: gadget: Don't set IMI for no_interrupt

 drivers/usb/dwc3/gadget.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

Changes in v3:
* Only set IMI to the last TRB of the chained TRBs

Changes in v2:
* Fix missing cover letter subject
* No need to check for the last chained TRB

base-commit: fb8f60dd1b67520e0e0d7978ef17d015690acfc1
-- 
2.28.0

[PATCH v3 1/2] usb: dwc3: gadget: Stop processing more requests on IMI

[Thinh Nguyen]

When servicing a transfer completion event, the dwc3 driver will reclaim
TRBs of started requests up to the request associated with the interrupt
event. Currently we don't check for interrupt due to missed isoc, and
the driver may attempt to reclaim TRBs beyond the associated event. This
causes invalid memory access when the hardware still owns the TRB. If
there's a missed isoc TRB with IMI (interrupt on missed isoc), make sure
to stop servicing further.

Note that only the last TRB of chained TRBs has its status updated with
missed isoc.

Fixes: 72246da40f37 ("usb: Introduce DesignWare USB3 DRD Driver")
Cc: stable@vger.kernel.org
Reported-by: Jeff Vanhoof <jdv1029@gmail.com>
Reported-by: Dan Vacura <w36195@motorola.com>
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
---
 Changes in v3:
 - None
 Changes in v2:
 - No need to check for CHN=0 since only the last TRB has its status
 updated to missed isoc


 drivers/usb/dwc3/gadget.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index dd8ecbe61bec..230b3c660054 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -3248,6 +3248,10 @@ static int dwc3_gadget_ep_reclaim_completed_trb(struct dwc3_ep *dep,
 	if (event->status & DEPEVT_STATUS_SHORT && !chain)
 		return 1;
 
+	if ((trb->ctrl & DWC3_TRB_CTRL_ISP_IMI) &&
+	    DWC3_TRB_SIZE_TRBSTS(trb->size) == DWC3_TRBSTS_MISSED_ISOC)
+		return 1;
+
 	if ((trb->ctrl & DWC3_TRB_CTRL_IOC) ||
 	    (trb->ctrl & DWC3_TRB_CTRL_LST))
 		return 1;
-- 
2.28.0

[PATCH v3 2/2] usb: dwc3: gadget: Don't set IMI for no_interrupt

[Thinh Nguyen]

The gadget driver may have a certain expectation of how the request
completion flow should be from to its configuration. Make sure the
controller driver respect that. That is, don't set IMI (Interrupt on
Missed Isoc) when usb_request->no_interrupt is set. Also, the driver
should only set IMI to the last TRB of a chain.

Fixes: 72246da40f37 ("usb: Introduce DesignWare USB3 DRD Driver")
Cc: stable@vger.kernel.org
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
---
 Changes in v3:
 - Set IMI to only the last TRB of a chain
 Changes in v2:
 - None

 drivers/usb/dwc3/gadget.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 230b3c660054..5fe2d136dff5 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1292,8 +1292,8 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
 			trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS;
 		}
 
-		/* always enable Interrupt on Missed ISOC */
-		trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
+		if (!no_interrupt && !chain)
+			trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
 		break;
 
 	case USB_ENDPOINT_XFER_BULK:
-- 
2.28.0

Re: [PATCH v3 2/2] usb: dwc3: gadget: Don't set IMI for no_interrupt

[Jeff Vanhoof]

On Tue, Oct 25, 2022 at 03:10:20PM -0700, Thinh Nguyen wrote:
> The gadget driver may have a certain expectation of how the request
> completion flow should be from to its configuration. Make sure the
> controller driver respect that. That is, don't set IMI (Interrupt on
> Missed Isoc) when usb_request->no_interrupt is set. Also, the driver
> should only set IMI to the last TRB of a chain.
> 
> Fixes: 72246da40f37 ("usb: Introduce DesignWare USB3 DRD Driver")
> Cc: stable@vger.kernel.org
> Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
> ---
>  Changes in v3:
>  - Set IMI to only the last TRB of a chain
>  Changes in v2:
>  - None
> 
>  drivers/usb/dwc3/gadget.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 230b3c660054..5fe2d136dff5 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -1292,8 +1292,8 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
>  			trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS;
>  		}
>  
> -		/* always enable Interrupt on Missed ISOC */
> -		trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
> +		if (!no_interrupt && !chain)
> +			trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI;
>  		break;
>  
>  	case USB_ENDPOINT_XFER_BULK:
> -- 
> 2.28.0
>

No new issues seen with these changes. Changes look good to me.

Reviewed-by: Jeff Vanhoof <jdv1029@gmail.com>
Tested-by: Jeff Vanhoof <jdv1029@gmail.com> 

Regards,
Jeff

Re: [PATCH v3 1/2] usb: dwc3: gadget: Stop processing more requests on IMI

[Jeff Vanhoof]

On Tue, Oct 25, 2022 at 03:10:14PM -0700, Thinh Nguyen wrote:
> When servicing a transfer completion event, the dwc3 driver will reclaim
> TRBs of started requests up to the request associated with the interrupt
> event. Currently we don't check for interrupt due to missed isoc, and
> the driver may attempt to reclaim TRBs beyond the associated event. This
> causes invalid memory access when the hardware still owns the TRB. If
> there's a missed isoc TRB with IMI (interrupt on missed isoc), make sure
> to stop servicing further.
> 
> Note that only the last TRB of chained TRBs has its status updated with
> missed isoc.
> 
> Fixes: 72246da40f37 ("usb: Introduce DesignWare USB3 DRD Driver")
> Cc: stable@vger.kernel.org
> Reported-by: Jeff Vanhoof <jdv1029@gmail.com>
> Reported-by: Dan Vacura <w36195@motorola.com>
> Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
> ---
>  Changes in v3:
>  - None
>  Changes in v2:
>  - No need to check for CHN=0 since only the last TRB has its status
>  updated to missed isoc
> 
> 
>  drivers/usb/dwc3/gadget.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index dd8ecbe61bec..230b3c660054 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -3248,6 +3248,10 @@ static int dwc3_gadget_ep_reclaim_completed_trb(struct dwc3_ep *dep,
>  	if (event->status & DEPEVT_STATUS_SHORT && !chain)
>  		return 1;
>  
> +	if ((trb->ctrl & DWC3_TRB_CTRL_ISP_IMI) &&
> +	    DWC3_TRB_SIZE_TRBSTS(trb->size) == DWC3_TRBSTS_MISSED_ISOC)
> +		return 1;
> +
>  	if ((trb->ctrl & DWC3_TRB_CTRL_IOC) ||
>  	    (trb->ctrl & DWC3_TRB_CTRL_LST))
>  		return 1;
> -- 
> 2.28.0
>

No new issues seen with these changes. Changes look good to me.

Reviewed-by: Jeff Vanhoof <jdv1029@gmail.com>
Tested-by: Jeff Vanhoof <jdv1029@gmail.com> 

Regards,
Jeff