Messages in this thread | | | From | Felipe Balbi <> | Subject | RE: [PATCH] usb: gadget: udc: fix the kernel NULL pointer in composite_setup | Date | Wed, 19 Jul 2017 10:50:58 +0300 |
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Hi,
(please don't top-post and also break your lines at 80-columns ;-)
"He, Bo" <bo.he@intel.com> writes: > 1. the issue reproduced very rarely, we run reboot test > reproduce the issue, it reproduced two times on two board after > more than 1500 cycles reboot.
That's fine, we, somehow, got a use-after-free on the tracepoints. I'm interested in fixing that without touching udc-core since that's a dwc3-only bug.
> 2. the kernel version is 4.4, the test case is cold reboot, I think it's not android patches cause it, it's the interrupt thread run after the udc->driver->unbind.
Yeah, I need you to try v4.13-rc1. v4.4 is *really* old. I can't accept your patch unless I'm certain the bug still exists.
> 3. I check more drivers, like amd5536_udc_stop, at91_stop, > atmel_usba_stop, bcm63xx_udc_stop, s3c_hsudc_stop, all the > interrupt disable will be in the udc_stop(), so we need > guarantee to stop the interrupt then release the resource.
Right, we also disable the interrupt on ->udc_stop(). See below:
static void __dwc3_gadget_stop(struct dwc3 *dwc) { dwc3_gadget_disable_irq(dwc); __dwc3_gadget_ep_disable(dwc->eps[0]); __dwc3_gadget_ep_disable(dwc->eps[1]); }
static int dwc3_gadget_stop(struct usb_gadget *g) { struct dwc3 *dwc = gadget_to_dwc(g); unsigned long flags; int epnum;
spin_lock_irqsave(&dwc->lock, flags);
if (pm_runtime_suspended(dwc->dev)) goto out;
__dwc3_gadget_stop(dwc);
for (epnum = 2; epnum < DWC3_ENDPOINTS_NUM; epnum++) { struct dwc3_ep *dep = dwc->eps[epnum];
if (!dep) continue;
if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING)) continue;
wait_event_lock_irq(dep->wait_end_transfer, !(dep->flags & DWC3_EP_END_TRANSFER_PENDING), dwc->lock); }
out: dwc->gadget_driver = NULL; spin_unlock_irqrestore(&dwc->lock, flags);
free_irq(dwc->irq_gadget, dwc->ev_buf);
return 0; }
-- balbi [unhandled content-type:application/pgp-signature]
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