Re: [PATCH v2 5/5] usb: xhci: Handle USB transaction error on address command

[Lu Baolu]

Hi,

On 07/27/2017 03:55 PM, Felipe Balbi wrote:
> Hi,
>
> Lu Baolu  writes:
>> Xhci driver handles USB transaction errors on transfer events,
>> but transaction errors are possible on address device command
>> completion events as well.
>>
>> The xHCI specification (section 4.6.5) says: A USB Transaction
>> Error Completion Code for an Address Device Command may be due
>> to a Stall response from a device. Software should issue a Disable
>> Slot Command for the Device Slot then an Enable Slot Command to
>> recover from this error.
>>
>> This patch handles USB transaction errors on address command
>> completion events. The related discussion threads can be found
>> through below links.
>>
>> http://marc.info/?l=linux-usb=149362010728921=2
>> http://marc.info/?l=linux-usb=149252752825755=2
>>
>> Suggested-by: Mathias Nyman 
>> Signed-off-by: Lu Baolu 
>> ---
>>  drivers/usb/host/xhci.c | 5 +
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
>> index d6b728d..95780f8 100644
>> --- a/drivers/usb/host/xhci.c
>> +++ b/drivers/usb/host/xhci.c
>> @@ -3822,6 +3822,11 @@ static int xhci_setup_device(struct usb_hcd *hcd, 
>> struct usb_device *udev,
>>  break;
>>  case COMP_USB_TRANSACTION_ERROR:
>>  dev_warn(>dev, "Device not responding to setup %s.\n", 
>> act);
>> +
>> +ret = xhci_disable_slot(xhci, udev->slot_id);
>> +if (!ret)
>> +xhci_alloc_dev(hcd, udev);
> aren't you leaking previously allocated virt_dev ?
>

When disable slot command completes, the command completion handler
will release the previous allocated virt_dev.

Best regards,
Lu Baolu

Re: [PATCH v2 5/5] usb: xhci: Handle USB transaction error on address command

[Lu Baolu]

Hi,

On 07/27/2017 03:55 PM, Felipe Balbi wrote:
> Hi,
>
> Lu Baolu  writes:
>> Xhci driver handles USB transaction errors on transfer events,
>> but transaction errors are possible on address device command
>> completion events as well.
>>
>> The xHCI specification (section 4.6.5) says: A USB Transaction
>> Error Completion Code for an Address Device Command may be due
>> to a Stall response from a device. Software should issue a Disable
>> Slot Command for the Device Slot then an Enable Slot Command to
>> recover from this error.
>>
>> This patch handles USB transaction errors on address command
>> completion events. The related discussion threads can be found
>> through below links.
>>
>> http://marc.info/?l=linux-usb=149362010728921=2
>> http://marc.info/?l=linux-usb=149252752825755=2
>>
>> Suggested-by: Mathias Nyman 
>> Signed-off-by: Lu Baolu 
>> ---
>>  drivers/usb/host/xhci.c | 5 +
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
>> index d6b728d..95780f8 100644
>> --- a/drivers/usb/host/xhci.c
>> +++ b/drivers/usb/host/xhci.c
>> @@ -3822,6 +3822,11 @@ static int xhci_setup_device(struct usb_hcd *hcd, 
>> struct usb_device *udev,
>>  break;
>>  case COMP_USB_TRANSACTION_ERROR:
>>  dev_warn(>dev, "Device not responding to setup %s.\n", 
>> act);
>> +
>> +ret = xhci_disable_slot(xhci, udev->slot_id);
>> +if (!ret)
>> +xhci_alloc_dev(hcd, udev);
> aren't you leaking previously allocated virt_dev ?
>

When disable slot command completes, the command completion handler
will release the previous allocated virt_dev.

Best regards,
Lu Baolu

Re: [PATCH v2 5/5] usb: xhci: Handle USB transaction error on address command

[Felipe Balbi]

Hi,

Lu Baolu  writes:
> Xhci driver handles USB transaction errors on transfer events,
> but transaction errors are possible on address device command
> completion events as well.
>
> The xHCI specification (section 4.6.5) says: A USB Transaction
> Error Completion Code for an Address Device Command may be due
> to a Stall response from a device. Software should issue a Disable
> Slot Command for the Device Slot then an Enable Slot Command to
> recover from this error.
>
> This patch handles USB transaction errors on address command
> completion events. The related discussion threads can be found
> through below links.
>
> http://marc.info/?l=linux-usb=149362010728921=2
> http://marc.info/?l=linux-usb=149252752825755=2
>
> Suggested-by: Mathias Nyman 
> Signed-off-by: Lu Baolu 
> ---
>  drivers/usb/host/xhci.c | 5 +
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
> index d6b728d..95780f8 100644
> --- a/drivers/usb/host/xhci.c
> +++ b/drivers/usb/host/xhci.c
> @@ -3822,6 +3822,11 @@ static int xhci_setup_device(struct usb_hcd *hcd, 
> struct usb_device *udev,
>   break;
>   case COMP_USB_TRANSACTION_ERROR:
>   dev_warn(>dev, "Device not responding to setup %s.\n", 
> act);
> +
> + ret = xhci_disable_slot(xhci, udev->slot_id);
> + if (!ret)
> + xhci_alloc_dev(hcd, udev);

aren't you leaking previously allocated virt_dev ?

-- 
balbi


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Description: PGP signature

Re: [PATCH v2 5/5] usb: xhci: Handle USB transaction error on address command

[Felipe Balbi]

Hi,

Lu Baolu  writes:
> Xhci driver handles USB transaction errors on transfer events,
> but transaction errors are possible on address device command
> completion events as well.
>
> The xHCI specification (section 4.6.5) says: A USB Transaction
> Error Completion Code for an Address Device Command may be due
> to a Stall response from a device. Software should issue a Disable
> Slot Command for the Device Slot then an Enable Slot Command to
> recover from this error.
>
> This patch handles USB transaction errors on address command
> completion events. The related discussion threads can be found
> through below links.
>
> http://marc.info/?l=linux-usb=149362010728921=2
> http://marc.info/?l=linux-usb=149252752825755=2
>
> Suggested-by: Mathias Nyman 
> Signed-off-by: Lu Baolu 
> ---
>  drivers/usb/host/xhci.c | 5 +
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
> index d6b728d..95780f8 100644
> --- a/drivers/usb/host/xhci.c
> +++ b/drivers/usb/host/xhci.c
> @@ -3822,6 +3822,11 @@ static int xhci_setup_device(struct usb_hcd *hcd, 
> struct usb_device *udev,
>   break;
>   case COMP_USB_TRANSACTION_ERROR:
>   dev_warn(>dev, "Device not responding to setup %s.\n", 
> act);
> +
> + ret = xhci_disable_slot(xhci, udev->slot_id);
> + if (!ret)
> + xhci_alloc_dev(hcd, udev);

aren't you leaking previously allocated virt_dev ?

-- 
balbi


signature.asc
Description: PGP signature

[PATCH v2 5/5] usb: xhci: Handle USB transaction error on address command

[Lu Baolu]

Xhci driver handles USB transaction errors on transfer events,
but transaction errors are possible on address device command
completion events as well.

The xHCI specification (section 4.6.5) says: A USB Transaction
Error Completion Code for an Address Device Command may be due
to a Stall response from a device. Software should issue a Disable
Slot Command for the Device Slot then an Enable Slot Command to
recover from this error.

This patch handles USB transaction errors on address command
completion events. The related discussion threads can be found
through below links.

http://marc.info/?l=linux-usb=149362010728921=2
http://marc.info/?l=linux-usb=149252752825755=2

Suggested-by: Mathias Nyman 
Signed-off-by: Lu Baolu 
---
 drivers/usb/host/xhci.c | 5 +
 1 file changed, 5 insertions(+)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index d6b728d..95780f8 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -3822,6 +3822,11 @@ static int xhci_setup_device(struct usb_hcd *hcd, struct 
usb_device *udev,
break;
case COMP_USB_TRANSACTION_ERROR:
dev_warn(>dev, "Device not responding to setup %s.\n", 
act);
+
+   ret = xhci_disable_slot(xhci, udev->slot_id);
+   if (!ret)
+   xhci_alloc_dev(hcd, udev);
+
ret = -EPROTO;
break;
case COMP_INCOMPATIBLE_DEVICE_ERROR:
-- 
2.7.4

[PATCH v2 5/5] usb: xhci: Handle USB transaction error on address command

[Lu Baolu]

Xhci driver handles USB transaction errors on transfer events,
but transaction errors are possible on address device command
completion events as well.

The xHCI specification (section 4.6.5) says: A USB Transaction
Error Completion Code for an Address Device Command may be due
to a Stall response from a device. Software should issue a Disable
Slot Command for the Device Slot then an Enable Slot Command to
recover from this error.

This patch handles USB transaction errors on address command
completion events. The related discussion threads can be found
through below links.

http://marc.info/?l=linux-usb=149362010728921=2
http://marc.info/?l=linux-usb=149252752825755=2

Suggested-by: Mathias Nyman 
Signed-off-by: Lu Baolu 
---
 drivers/usb/host/xhci.c | 5 +
 1 file changed, 5 insertions(+)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index d6b728d..95780f8 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -3822,6 +3822,11 @@ static int xhci_setup_device(struct usb_hcd *hcd, struct 
usb_device *udev,
break;
case COMP_USB_TRANSACTION_ERROR:
dev_warn(>dev, "Device not responding to setup %s.\n", 
act);
+
+   ret = xhci_disable_slot(xhci, udev->slot_id);
+   if (!ret)
+   xhci_alloc_dev(hcd, udev);
+
ret = -EPROTO;
break;
case COMP_INCOMPATIBLE_DEVICE_ERROR:
-- 
2.7.4