* [bug report] usb: cdns3: Add Cadence USB3 DRD Driver
@ 2019-09-24 13:55 Dan Carpenter
2019-09-25 4:11 ` Pawel Laszczak
0 siblings, 1 reply; 2+ messages in thread
From: Dan Carpenter @ 2019-09-24 13:55 UTC (permalink / raw)
To: Pawel Laszczak; +Cc: linux-usb
Hello Pawel Laszczak,
The patch 7733f6c32e36: "usb: cdns3: Add Cadence USB3 DRD Driver"
from Aug 26, 2019, leads to the following static checker warning:
drivers/usb/cdns3/ep0.c:335 cdns3_ep0_feature_handle_device()
error: scheduling with locks held: 'spin_lock:lock'
drivers/usb/cdns3/ep0.c
309
310 priv_dev->u2_allowed = !!set;
311 break;
312 case USB_DEVICE_LTM_ENABLE:
313 ret = -EINVAL;
314 break;
315 case USB_DEVICE_TEST_MODE:
316 if (state != USB_STATE_CONFIGURED || speed > USB_SPEED_HIGH)
317 return -EINVAL;
318
319 tmode = le16_to_cpu(ctrl->wIndex);
320
321 if (!set || (tmode & 0xff) != 0)
322 return -EINVAL;
323
324 switch (tmode >> 8) {
325 case TEST_J:
326 case TEST_K:
327 case TEST_SE0_NAK:
328 case TEST_PACKET:
329 cdns3_ep0_complete_setup(priv_dev, 0, 1);
330 /**
331 * Little delay to give the controller some time
332 * for sending status stage.
333 * This time should be less then 3ms.
334 */
335 usleep_range(1000, 2000);
^^^^^^^^^^^^^^^^^^^^^^^^
This is called with locks held and IRQs disabled in
cdns3_device_thread_irq_handler(). The call tree is:
cdns3_device_thread_irq_handler()
cdns3_check_ep0_interrupt_proceed()
cdns3_ep0_setup_phase()
cdns3_ep0_standard_request()
cdns3_req_ep0_handle_feature()
cdns3_ep0_feature_handle_device()
You would need to have certain debug config options enabled to see the
might_sleep() warnings and probably USB_DEVICE_TEST_MODE isn't used
very often.
336 cdns3_set_register_bit(&priv_dev->regs->usb_cmd,
337 USB_CMD_STMODE |
338 USB_STS_TMODE_SEL(tmode - 1));
339 break;
340 default:
341 ret = -EINVAL;
342 }
343 break;
344 default:
345 ret = -EINVAL;
346 }
regards,
dan carpenter
^ permalink raw reply [flat|nested] 2+ messages in thread
* RE: [bug report] usb: cdns3: Add Cadence USB3 DRD Driver
2019-09-24 13:55 [bug report] usb: cdns3: Add Cadence USB3 DRD Driver Dan Carpenter
@ 2019-09-25 4:11 ` Pawel Laszczak
0 siblings, 0 replies; 2+ messages in thread
From: Pawel Laszczak @ 2019-09-25 4:11 UTC (permalink / raw)
To: Dan Carpenter; +Cc: linux-usb
Hi Dan,
>Hello Pawel Laszczak,
>
>The patch 7733f6c32e36: "usb: cdns3: Add Cadence USB3 DRD Driver"
>from Aug 26, 2019, leads to the following static checker warning:
>
> drivers/usb/cdns3/ep0.c:335 cdns3_ep0_feature_handle_device()
> error: scheduling with locks held: 'spin_lock:lock'
>
>drivers/usb/cdns3/ep0.c
> 309
> 310 priv_dev->u2_allowed = !!set;
> 311 break;
> 312 case USB_DEVICE_LTM_ENABLE:
> 313 ret = -EINVAL;
> 314 break;
> 315 case USB_DEVICE_TEST_MODE:
> 316 if (state != USB_STATE_CONFIGURED || speed > USB_SPEED_HIGH)
> 317 return -EINVAL;
> 318
> 319 tmode = le16_to_cpu(ctrl->wIndex);
> 320
> 321 if (!set || (tmode & 0xff) != 0)
> 322 return -EINVAL;
> 323
> 324 switch (tmode >> 8) {
> 325 case TEST_J:
> 326 case TEST_K:
> 327 case TEST_SE0_NAK:
> 328 case TEST_PACKET:
> 329 cdns3_ep0_complete_setup(priv_dev, 0, 1);
> 330 /**
> 331 * Little delay to give the controller some time
> 332 * for sending status stage.
> 333 * This time should be less then 3ms.
> 334 */
> 335 usleep_range(1000, 2000);
> ^^^^^^^^^^^^^^^^^^^^^^^^
>This is called with locks held and IRQs disabled in
>cdns3_device_thread_irq_handler(). The call tree is:
>
>cdns3_device_thread_irq_handler()
> cdns3_check_ep0_interrupt_proceed()
> cdns3_ep0_setup_phase()
> cdns3_ep0_standard_request()
> cdns3_req_ep0_handle_feature()
> cdns3_ep0_feature_handle_device()
>
>You would need to have certain debug config options enabled to see the
>might_sleep() warnings and probably USB_DEVICE_TEST_MODE isn't used
>very often.
It's very rarely used options. This part is required only during USB Certification process to pass
some tests. After completion the device under test can be even rebooted.
I think that It should be replaced by udelay/mdelay function. I understand that the problem occurred
because we can't use sleep functions when lock is held, or interrupt are disabled.
I will post the fix patch ASAP.
Thank you for letting me know.
>
> 336 cdns3_set_register_bit(&priv_dev->regs->usb_cmd,
> 337 USB_CMD_STMODE |
> 338 USB_STS_TMODE_SEL(tmode - 1));
> 339 break;
> 340 default:
> 341 ret = -EINVAL;
> 342 }
> 343 break;
> 344 default:
> 345 ret = -EINVAL;
> 346 }
>
>regards,
>dan carpenter
Regards,
Pawell
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2019-09-25 4:11 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-09-24 13:55 [bug report] usb: cdns3: Add Cadence USB3 DRD Driver Dan Carpenter
2019-09-25 4:11 ` Pawel Laszczak
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).