Hi Felipe, On 26 May 2016 at 14:22, Felipe Balbi <balbi@xxxxxxxxxx> wrote: > > Hi, > > Baolin Wang <baolin.wang@xxxxxxxxxx> writes: >> When handling the endpoint interrupt handler, it maybe disable the endpoint >> from another core user to set the USB endpoint descriptor pointor to be NULL >> while issuing usb_gadget_giveback_request() function to release lock. So it >> will be one bug to check the endpoint type by usb_endpoint_xfer_xxx() APIs with >> one NULL USB endpoint descriptor. > > too complex, Baolin :-) Can you see if this helps: > > https://git.kernel.org/cgit/linux/kernel/git/balbi/usb.git/commit/?id=88bf752cfb55e57a78e27c931c9fef63240c739a > > The only situation when that can happen is while we drop our lock on > dwc3_gadget_giveback(). OK, But line 1974 and line 2025 as below may be at risk? So I think can we have a common place to solve the problem in case usb_endpoint_xfer_xxx() APIs are issued at this risk? What do you think? Thanks. 1956 static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep, 1957 const struct dwc3_event_depevt *event, int status) 1958 { 1959 struct dwc3_request *req; 1960 struct dwc3_trb *trb; 1961 unsigned int slot; 1962 unsigned int i; 1963 int ret; 1964 1965 do { 1966 req = next_request(&dep->req_queued); 1967 if (WARN_ON_ONCE(!req)) 1968 return 1; 1969 1970 i = 0; 1971 do { 1972 slot = req->start_slot + i; 1973 if ((slot == DWC3_TRB_NUM - 1) && 1974 usb_endpoint_xfer_isoc(dep->endpoint.desc)) 1975 slot++; 1976 slot %= DWC3_TRB_NUM; 1977 trb = &dep->trb_pool[slot]; 1978 1979 ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb, 1980 event, status); 1981 if (ret) 1982 break; 1983 } while (++i < req->request.num_mapped_sgs); 1984 1985 dwc3_gadget_giveback(dep, req, status); 1986 1987 if (ret) 1988 break; 1989 } while (1); ....... 2011 static void dwc3_endpoint_transfer_complete(struct dwc3 *dwc, 2012 struct dwc3_ep *dep, const struct dwc3_event_depevt *event) 2013 { 2014 unsigned status = 0; 2015 int clean_busy; 2016 u32 is_xfer_complete; 2017 2018 is_xfer_complete = (event->endpoint_event == DWC3_DEPEVT_XFERCOMPLETE); 2019 2020 if (event->status & DEPEVT_STATUS_BUSERR) 2021 status = -ECONNRESET; 2022 2023 clean_busy = dwc3_cleanup_done_reqs(dwc, dep, event, status); 2024 if (clean_busy && (is_xfer_complete || 2025 usb_endpoint_xfer_isoc(dep->endpoint.desc))) 2026 dep->flags &= ~DWC3_EP_BUSY; > > -- > balbi -- Baolin.wang Best Regards -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
