[PATCH] usb: dwc3: gadget: skip Set/Clear Halt when invalid

[PATCH] usb: dwc3: gadget: skip Set/Clear Halt when invalid

[Felipe Balbi]

At least macOS seems to be sending
ClearFeature(ENDPOINT_HALT) to endpoints which
aren't Halted. This makes DWC3's CLEARSTALL command
time out which causes several issues for the driver.

Instead, let's just return 0 and bail out early.

Cc: <stable@vger.kernel.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
---

this falls into "has never worked before" category, so I'll be sending
it together with other patches for v4.11 merge window. Still, it's a
valid bug that's likely needed for stable trees.

 drivers/usb/dwc3/gadget.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 6faf484e5dfc..0a664d8eba3f 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1379,6 +1379,9 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
 		unsigned transfer_in_flight;
 		unsigned started;
 
+		if (dep->flags & DWC3_EP_STALL)
+			return 0;
+
 		if (dep->number > 1)
 			trb = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
 		else
@@ -1400,6 +1403,8 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
 		else
 			dep->flags |= DWC3_EP_STALL;
 	} else {
+		if (!(dep->flags & DWC3_EP_STALL))
+			return 0;
 
 		ret = dwc3_send_clear_stall_ep_cmd(dep);
 		if (ret)
-- 
2.11.0.295.gd7dffce1ce

RE: [PATCH] usb: dwc3: gadget: skip Set/Clear Halt when invalid

[Felipe Balbi]

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Hi Thinh,

Thinh Nguyen <Thinh.Nguyen@synopsys.com> writes:
>>  drivers/usb/dwc3/gadget.c | 5 +++++
>>  1 file changed, 5 insertions(+)
>> 
>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>> index 6faf484e5dfc..0a664d8eba3f 100644
>> --- a/drivers/usb/dwc3/gadget.c
>> +++ b/drivers/usb/dwc3/gadget.c
>> @@ -1379,6 +1379,9 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep
>> *dep, int value, int protocol)
>>  		unsigned transfer_in_flight;
>>  		unsigned started;
>> 
>> +		if (dep->flags & DWC3_EP_STALL)
>> +			return 0;
>> +
>>  		if (dep->number > 1)
>>  			trb = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
>>  		else
>> @@ -1400,6 +1403,8 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep
>> *dep, int value, int protocol)
>>  		else
>>  			dep->flags |= DWC3_EP_STALL;
>>  	} else {
>> +		if (!(dep->flags & DWC3_EP_STALL))
>> +			return 0;
>> 
>>  		ret = dwc3_send_clear_stall_ep_cmd(dep);
>>  		if (ret)
>> --
>> 2.11.0.295.gd7dffce1ce
>> 
>> --
>
> I encounter an issue when I test mainline with USB 3 CV MSC test and
> bisected to this patch.
>
> Tester: USB 3 CV test (v2.1.3.0).
> Function Driver: f_mass_storage
> Reproducibility: always 
>
> The failure occurs under MSC Error Recovery Test (TD 1.4).
>
> Failure from the test sequence as follow (MSC compliance test spec) :
> 1. Place the device in the desired starting state.
> 2. Issue a Case 9 CBW (see Table 2) but with invalid signature of 0xDEADBEEF.
> 3. Issue several In requests to the Bulk-Only Data Interface Bulk In endpoint. Verify a
> STALL handshake is returned. If STALL handshake is not returned, skip to step 11.
> 4. Issue a Get_Status(endpoint) request targeting the Bulk-Only Data Interface bulk In
> endpoint. Verify that it completes normally, reports endpoint halt status.
>
>  ***After this point the device idles for 10 seconds and resets. ***
>
> Test fails.

I've been looking at this and based on sniffer and dwc3 tracepoints, it
seems like dwc3 is behaving properly. The real issue seems to be that
g_mass_storage isn't queueing a new request to IN endpoint.

I'll continue debugging this and try to find a solution that doesn't
involve reverting $subject.

-- 
balbi

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RE: [PATCH] usb: dwc3: gadget: skip Set/Clear Halt when invalid

[Felipe Balbi]

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Felipe Balbi <felipe.balbi@linux.intel.com> writes:

> Hi Thinh,
>
> Thinh Nguyen <Thinh.Nguyen@synopsys.com> writes:
>>>  drivers/usb/dwc3/gadget.c | 5 +++++
>>>  1 file changed, 5 insertions(+)
>>> 
>>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>>> index 6faf484e5dfc..0a664d8eba3f 100644
>>> --- a/drivers/usb/dwc3/gadget.c
>>> +++ b/drivers/usb/dwc3/gadget.c
>>> @@ -1379,6 +1379,9 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep
>>> *dep, int value, int protocol)
>>>  		unsigned transfer_in_flight;
>>>  		unsigned started;
>>> 
>>> +		if (dep->flags & DWC3_EP_STALL)
>>> +			return 0;
>>> +
>>>  		if (dep->number > 1)
>>>  			trb = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
>>>  		else
>>> @@ -1400,6 +1403,8 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep
>>> *dep, int value, int protocol)
>>>  		else
>>>  			dep->flags |= DWC3_EP_STALL;
>>>  	} else {
>>> +		if (!(dep->flags & DWC3_EP_STALL))
>>> +			return 0;
>>> 
>>>  		ret = dwc3_send_clear_stall_ep_cmd(dep);
>>>  		if (ret)
>>> --
>>> 2.11.0.295.gd7dffce1ce
>>> 
>>> --
>>
>> I encounter an issue when I test mainline with USB 3 CV MSC test and
>> bisected to this patch.
>>
>> Tester: USB 3 CV test (v2.1.3.0).
>> Function Driver: f_mass_storage
>> Reproducibility: always 
>>
>> The failure occurs under MSC Error Recovery Test (TD 1.4).
>>
>> Failure from the test sequence as follow (MSC compliance test spec) :
>> 1. Place the device in the desired starting state.
>> 2. Issue a Case 9 CBW (see Table 2) but with invalid signature of 0xDEADBEEF.
>> 3. Issue several In requests to the Bulk-Only Data Interface Bulk In endpoint. Verify a
>> STALL handshake is returned. If STALL handshake is not returned, skip to step 11.
>> 4. Issue a Get_Status(endpoint) request targeting the Bulk-Only Data Interface bulk In
>> endpoint. Verify that it completes normally, reports endpoint halt status.
>>
>>  ***After this point the device idles for 10 seconds and resets. ***
>>
>> Test fails.
>
> I've been looking at this and based on sniffer and dwc3 tracepoints, it
> seems like dwc3 is behaving properly. The real issue seems to be that
> g_mass_storage isn't queueing a new request to IN endpoint.
>
> I'll continue debugging this and try to find a solution that doesn't
> involve reverting $subject.

oh no, wait. ep2out misses XferInProgress:

    file-storage-1592  [000] d..1   152.809922: dwc3_ep_queue: ep2out: req ffff88003cd6ee40 length 0/512 zsI ==> -115
    file-storage-1592  [000] d..1   152.809931: dwc3_prepare_trb: ep2out: 3/8 trb ffff88003a196050 buf 000000002d5e4000 size 512 ctrl 00000819 (HlcS:sC:normal)
    file-storage-1592  [000] d..1   152.809942: dwc3_gadget_ep_cmd: ep2out: cmd 'Update Transfer' [262151] params 00000000 00000000 00000000 --> status: Successful
    file-storage-1592  [000] ....   152.809951: usb_ep_queue: ep2out: length 0/512 sgs 0/0 stream 0 zsI status -115 --> 0
     irq/34-dwc3-1593  [001] d..1   152.810212: dwc3_event: event (0000c040): ep0out: Transfer Complete [Setup Phase]
     irq/34-dwc3-1593  [001] d..1   152.810218: dwc3_ctrl_req: bRequestType 02 bRequest 01 wValue 0000 wIndex 0002 wLength 0
     irq/34-dwc3-1593  [001] d..1   152.810228: __dwc3_gadget_ep_set_halt: ep2out: NOT stalled

Sniffer shows me this completing, but I don't see IRQ for this.

-- 
balbi

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RE: [PATCH] usb: dwc3: gadget: skip Set/Clear Halt when invalid

[Felipe Balbi]

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Hi,

Felipe Balbi <felipe.balbi@linux.intel.com> writes:
>> Thinh Nguyen <Thinh.Nguyen@synopsys.com> writes:
>>>>  drivers/usb/dwc3/gadget.c | 5 +++++
>>>>  1 file changed, 5 insertions(+)
>>>> 
>>>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>>>> index 6faf484e5dfc..0a664d8eba3f 100644
>>>> --- a/drivers/usb/dwc3/gadget.c
>>>> +++ b/drivers/usb/dwc3/gadget.c
>>>> @@ -1379,6 +1379,9 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep
>>>> *dep, int value, int protocol)
>>>>  		unsigned transfer_in_flight;
>>>>  		unsigned started;
>>>> 
>>>> +		if (dep->flags & DWC3_EP_STALL)
>>>> +			return 0;
>>>> +
>>>>  		if (dep->number > 1)
>>>>  			trb = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
>>>>  		else
>>>> @@ -1400,6 +1403,8 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep
>>>> *dep, int value, int protocol)
>>>>  		else
>>>>  			dep->flags |= DWC3_EP_STALL;
>>>>  	} else {
>>>> +		if (!(dep->flags & DWC3_EP_STALL))
>>>> +			return 0;
>>>> 
>>>>  		ret = dwc3_send_clear_stall_ep_cmd(dep);
>>>>  		if (ret)
>>>> --
>>>> 2.11.0.295.gd7dffce1ce
>>>> 
>>>> --
>>>
>>> I encounter an issue when I test mainline with USB 3 CV MSC test and
>>> bisected to this patch.
>>>
>>> Tester: USB 3 CV test (v2.1.3.0).
>>> Function Driver: f_mass_storage
>>> Reproducibility: always 
>>>
>>> The failure occurs under MSC Error Recovery Test (TD 1.4).
>>>
>>> Failure from the test sequence as follow (MSC compliance test spec) :
>>> 1. Place the device in the desired starting state.
>>> 2. Issue a Case 9 CBW (see Table 2) but with invalid signature of 0xDEADBEEF.
>>> 3. Issue several In requests to the Bulk-Only Data Interface Bulk In endpoint. Verify a
>>> STALL handshake is returned. If STALL handshake is not returned, skip to step 11.
>>> 4. Issue a Get_Status(endpoint) request targeting the Bulk-Only Data Interface bulk In
>>> endpoint. Verify that it completes normally, reports endpoint halt status.
>>>
>>>  ***After this point the device idles for 10 seconds and resets. ***
>>>
>>> Test fails.
>>
>> I've been looking at this and based on sniffer and dwc3 tracepoints, it
>> seems like dwc3 is behaving properly. The real issue seems to be that
>> g_mass_storage isn't queueing a new request to IN endpoint.
>>
>> I'll continue debugging this and try to find a solution that doesn't
>> involve reverting $subject.
>
> oh no, wait. ep2out misses XferInProgress:
>
>     file-storage-1592  [000] d..1   152.809922: dwc3_ep_queue: ep2out: req ffff88003cd6ee40 length 0/512 zsI ==> -115
>     file-storage-1592  [000] d..1   152.809931: dwc3_prepare_trb: ep2out: 3/8 trb ffff88003a196050 buf 000000002d5e4000 size 512 ctrl 00000819 (HlcS:sC:normal)
>     file-storage-1592  [000] d..1   152.809942: dwc3_gadget_ep_cmd: ep2out: cmd 'Update Transfer' [262151] params 00000000 00000000 00000000 --> status: Successful
>     file-storage-1592  [000] ....   152.809951: usb_ep_queue: ep2out: length 0/512 sgs 0/0 stream 0 zsI status -115 --> 0
>      irq/34-dwc3-1593  [001] d..1   152.810212: dwc3_event: event (0000c040): ep0out: Transfer Complete [Setup Phase]
>      irq/34-dwc3-1593  [001] d..1   152.810218: dwc3_ctrl_req: bRequestType 02 bRequest 01 wValue 0000 wIndex 0002 wLength 0
>      irq/34-dwc3-1593  [001] d..1   152.810228: __dwc3_gadget_ep_set_halt: ep2out: NOT stalled
>
> Sniffer shows me this completing, but I don't see IRQ for this.

BTW, I just tested without $subject and it fails the same way. This is
caused by something else. Can you rerun your bisect while I look at the
problem here?

-- 
balbi

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RE: [PATCH] usb: dwc3: gadget: skip Set/Clear Halt when invalid

[Felipe Balbi]

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Hi,

Felipe Balbi <felipe.balbi@linux.intel.com> writes:
>>> I've been looking at this and based on sniffer and dwc3 tracepoints, it
>>> seems like dwc3 is behaving properly. The real issue seems to be that
>>> g_mass_storage isn't queueing a new request to IN endpoint.
>>>
>>> I'll continue debugging this and try to find a solution that doesn't
>>> involve reverting $subject.
>>
>> oh no, wait. ep2out misses XferInProgress:
>>
>>     file-storage-1592  [000] d..1   152.809922: dwc3_ep_queue: ep2out: req ffff88003cd6ee40 length 0/512 zsI ==> -115
>>     file-storage-1592  [000] d..1   152.809931: dwc3_prepare_trb: ep2out: 3/8 trb ffff88003a196050 buf 000000002d5e4000 size 512 ctrl 00000819 (HlcS:sC:normal)
>>     file-storage-1592  [000] d..1   152.809942: dwc3_gadget_ep_cmd: ep2out: cmd 'Update Transfer' [262151] params 00000000 00000000 00000000 --> status: Successful
>>     file-storage-1592  [000] ....   152.809951: usb_ep_queue: ep2out: length 0/512 sgs 0/0 stream 0 zsI status -115 --> 0
>>      irq/34-dwc3-1593  [001] d..1   152.810212: dwc3_event: event (0000c040): ep0out: Transfer Complete [Setup Phase]
>>      irq/34-dwc3-1593  [001] d..1   152.810218: dwc3_ctrl_req: bRequestType 02 bRequest 01 wValue 0000 wIndex 0002 wLength 0
>>      irq/34-dwc3-1593  [001] d..1   152.810228: __dwc3_gadget_ep_set_halt: ep2out: NOT stalled
>>
>> Sniffer shows me this completing, but I don't see IRQ for this.
>
> BTW, I just tested without $subject and it fails the same way. This is
> caused by something else. Can you rerun your bisect while I look at the
> problem here?

Okay, found it. This is caused by the ep_dequeue bug that I already
fixed. see [1] for that

[1] https://marc.info/?i=20170217105759.24356-1-felipe.balbi@linux.intel.com

-- 
balbi

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Re: [PATCH] usb: dwc3: gadget: skip Set/Clear Halt when invalid

[Felipe Balbi]

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Hi John,

Felipe Balbi <felipe.balbi@linux.intel.com> writes:
> At least macOS seems to be sending
> ClearFeature(ENDPOINT_HALT) to endpoints which
> aren't Halted. This makes DWC3's CLEARSTALL command
> time out which causes several issues for the driver.
>
> Instead, let's just return 0 and bail out early.
>
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
> ---
>
> this falls into "has never worked before" category, so I'll be sending
> it together with other patches for v4.11 merge window. Still, it's a
> valid bug that's likely needed for stable trees.
>
>  drivers/usb/dwc3/gadget.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 6faf484e5dfc..0a664d8eba3f 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -1379,6 +1379,9 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
>  		unsigned transfer_in_flight;
>  		unsigned started;
>  
> +		if (dep->flags & DWC3_EP_STALL)
> +			return 0;
> +
>  		if (dep->number > 1)
>  			trb = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
>  		else
> @@ -1400,6 +1403,8 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
>  		else
>  			dep->flags |= DWC3_EP_STALL;
>  	} else {
> +		if (!(dep->flags & DWC3_EP_STALL))
> +			return 0;
>  
>  		ret = dwc3_send_clear_stall_ep_cmd(dep);
>  		if (ret)

Reviving this old thread here. While $subject allowed dwc3 to work when
attached to macOS Host, I fear that we might have more issues than not
in the future. The reason is that USB20 spec allows hosts to use
ClearFeature(ENDPOINT_HALT) as a "Reset Data Toggle/SeqN" hint.

With this, we're basically blocking that possibility. Still, without
$subject, ClearStall commands were timing out. I'll try to do a local
revert here and check what happens in this case, but would you have any
idea why ClearStall would time out like that?

-- 
balbi

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Re: [PATCH] usb: dwc3: gadget: skip Set/Clear Halt when invalid

[John Youn]

On 04/04/2017 01:09 AM, Felipe Balbi wrote:
>
> Hi John,
>
> Felipe Balbi <felipe.balbi@linux.intel.com> writes:
>> At least macOS seems to be sending
>> ClearFeature(ENDPOINT_HALT) to endpoints which
>> aren't Halted. This makes DWC3's CLEARSTALL command
>> time out which causes several issues for the driver.
>>
>> Instead, let's just return 0 and bail out early.
>>
>> Cc: <stable@vger.kernel.org>
>> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
>> ---
>>
>> this falls into "has never worked before" category, so I'll be sending
>> it together with other patches for v4.11 merge window. Still, it's a
>> valid bug that's likely needed for stable trees.
>>
>>  drivers/usb/dwc3/gadget.c | 5 +++++
>>  1 file changed, 5 insertions(+)
>>
>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>> index 6faf484e5dfc..0a664d8eba3f 100644
>> --- a/drivers/usb/dwc3/gadget.c
>> +++ b/drivers/usb/dwc3/gadget.c
>> @@ -1379,6 +1379,9 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
>>  		unsigned transfer_in_flight;
>>  		unsigned started;
>>
>> +		if (dep->flags & DWC3_EP_STALL)
>> +			return 0;
>> +
>>  		if (dep->number > 1)
>>  			trb = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
>>  		else
>> @@ -1400,6 +1403,8 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
>>  		else
>>  			dep->flags |= DWC3_EP_STALL;
>>  	} else {
>> +		if (!(dep->flags & DWC3_EP_STALL))
>> +			return 0;
>>
>>  		ret = dwc3_send_clear_stall_ep_cmd(dep);
>>  		if (ret)
>
> Reviving this old thread here. While $subject allowed dwc3 to work when
> attached to macOS Host, I fear that we might have more issues than not
> in the future. The reason is that USB20 spec allows hosts to use
> ClearFeature(ENDPOINT_HALT) as a "Reset Data Toggle/SeqN" hint.
>
> With this, we're basically blocking that possibility. Still, without
> $subject, ClearStall commands were timing out. I'll try to do a local
> revert here and check what happens in this case, but would you have any
> idea why ClearStall would time out like that?
>

Hi Felipe,

I think Thinh Nguyen e-mailed you about this before saying it caused a
regression for us. But he has not had time to look into it further and
follow-up yet.

No idea about the timing out on Mac though. We can try to reproduce
this when we have some time and take a look. Do you have a USB trace?

Regards,
John

Re: [PATCH] usb: dwc3: gadget: skip Set/Clear Halt when invalid

[Felipe Balbi]

Hi,

John Youn <John.Youn@synopsys.com> writes:
>> Felipe Balbi <felipe.balbi@linux.intel.com> writes:
>>> At least macOS seems to be sending
>>> ClearFeature(ENDPOINT_HALT) to endpoints which
>>> aren't Halted. This makes DWC3's CLEARSTALL command
>>> time out which causes several issues for the driver.
>>>
>>> Instead, let's just return 0 and bail out early.
>>>
>>> Cc: <stable@vger.kernel.org>
>>> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
>>> ---
>>>
>>> this falls into "has never worked before" category, so I'll be sending
>>> it together with other patches for v4.11 merge window. Still, it's a
>>> valid bug that's likely needed for stable trees.
>>>
>>>  drivers/usb/dwc3/gadget.c | 5 +++++
>>>  1 file changed, 5 insertions(+)
>>>
>>> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
>>> index 6faf484e5dfc..0a664d8eba3f 100644
>>> --- a/drivers/usb/dwc3/gadget.c
>>> +++ b/drivers/usb/dwc3/gadget.c
>>> @@ -1379,6 +1379,9 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
>>>  		unsigned transfer_in_flight;
>>>  		unsigned started;
>>>
>>> +		if (dep->flags & DWC3_EP_STALL)
>>> +			return 0;
>>> +
>>>  		if (dep->number > 1)
>>>  			trb = dwc3_ep_prev_trb(dep, dep->trb_enqueue);
>>>  		else
>>> @@ -1400,6 +1403,8 @@ int __dwc3_gadget_ep_set_halt(struct dwc3_ep *dep, int value, int protocol)
>>>  		else
>>>  			dep->flags |= DWC3_EP_STALL;
>>>  	} else {
>>> +		if (!(dep->flags & DWC3_EP_STALL))
>>> +			return 0;
>>>
>>>  		ret = dwc3_send_clear_stall_ep_cmd(dep);
>>>  		if (ret)
>>
>> Reviving this old thread here. While $subject allowed dwc3 to work when
>> attached to macOS Host, I fear that we might have more issues than not
>> in the future. The reason is that USB20 spec allows hosts to use
>> ClearFeature(ENDPOINT_HALT) as a "Reset Data Toggle/SeqN" hint.
>>
>> With this, we're basically blocking that possibility. Still, without
>> $subject, ClearStall commands were timing out. I'll try to do a local
>> revert here and check what happens in this case, but would you have any
>> idea why ClearStall would time out like that?
>>
>
> Hi Felipe,
>
> I think Thinh Nguyen e-mailed you about this before saying it caused a
> regression for us. But he has not had time to look into it further and
> follow-up yet.
>
> No idea about the timing out on Mac though. We can try to reproduce
> this when we have some time and take a look. Do you have a USB trace?

not anymore, but as soon I have some free time, I can revert the patch
locally and try to reproduce. I'll also implement a little libusb-based
test to issue that request hundreds of times in a row and see if I can
force the problem to happen ;-)

Thanks for responding so quickly :-)

-- 
balbi