Hi Ahmed, Yes you are right. Regards, Dev -----Original Message----- From: Ahmed Ragab [mailto:elmasri.ahmed@xxxxxxxxx] Sent: Friday, February 05, 2010 10:12 AM To: SINGH DEVENDRA-DHGW76 Cc: linux-bluetooth@xxxxxxxxxxxxxxx Subject: Re: Kernel panic when SCO connection I think we where writing at the same time > Hi dev, > > Thanks for your suggestions i followed it , however i am have problem > with step 3. > In step 3 >> int len = (urb->iso_frame_desc[i].actual_length > >> urb->iso_frame_desc[i].length)? >> urb->iso_frame_desc[i].length: >> urb->iso_frame_desc[i].actual_length; >> >> __recv_frame(husb, >> _urb->type, >> urb->transfer_buffer + urb->iso_frame_desc[i].offset, >> len); > where in the below snapshot from hci_usb.c should we make this work around > > for (i=0; i < urb->number_of_packets; i++) { > BT_DBG("desc %d status %d offset %d len %d", i, > urb->iso_frame_desc[i].status, > urb->iso_frame_desc[i].offset, > > urb->iso_frame_desc[i].actual_length); > > if (!urb->iso_frame_desc[i].status) { > husb->hdev->stat.byte_rx += > urb->iso_frame_desc[i].actual_length; > hci_recv_fragment(husb->hdev, > _urb->type, > urb->transfer_buffer + > urb->iso_frame_desc[i].offset, > > urb->iso_frame_desc[i].actual_length); > } > } > #else > ; > #endif > } else { > husb->hdev->stat.byte_rx += count; > err = hci_recv_fragment(husb->hdev, _urb->type, > urb->transfer_buffer, count); > if (err < 0) { > BT_ERR("%s corrupted packet: type %d count %d", > husb->hdev->name, _urb->type, > count); > hdev->stat.err_rx++; > } > } > > Thanks Ahmed > > > > On 4 February 2010 06:36, SINGH DEVENDRA-DHGW76 <DevSingh@xxxxxxxxxxxx> wrote: >> Hi, >> >> I noticed the same problem when I was working with a embedded board >> with Broadcom chipset and Linux kernel 2.6.18 (I guess). Use case >> was, a Bluetooth based headset sends data to the CSR Bluetooth >> dongle(USB), which in turn provide data to the Application through bluez stack. >> >> >> Following were my observation: >> >> 1. Board processor is not strong enough and so there was no URB in >> the queue and audio data was getting accumulated in the USB host controller. >> There are only 2 Rx URBs (hci_usb.h: #define HCI_MAX_ISOC_RX 2). >> 2. Actual length of data for data in the URB is reaching to the level >> of 1K bytes. (Max ISOC data length) however Bluetooth driver is >> expecting 10 packets of 64 bytes each. hci_usb_isoc_rx_submit >> function in hci_usb.c file. >> 3. Completion routine copies data for actual length returned for >> packet that could be 1024 while limit for one packet is 64B only. (hci_usb.c: >> hci_usb_rx_complete function). >> 4. These "SCO packet for unknown connection handle" error logs >> further complicated the problem as this will further eat-up cpu time. >> >> >> Cause: >> >> Max length of available transfer buffer could be 640 bytes (that's >> depend upon the buffer index) and copying big chunk of data was >> resulting into memory overrun and kernel memory was getting corrupted >> that results in un-expected behavior line connection break, lots of >> noise and even kernel panic some times. >> >> >> Following was the work around: >> >> 1. Increased number of Rx URBs to 6. (hci_usb.h: #define >> HCI_MAX_ISOC_RX 6). >> 2. Increased transfer buffer size to 1.5K. >> 3. Put a check in completion routine that in case actual length is >> more then frame length then copy only frame length size data as follows: >> >> int len = (urb->iso_frame_desc[i].actual_length > >> urb->iso_frame_desc[i].length)? >> urb->iso_frame_desc[i].length: >> urb->iso_frame_desc[i].actual_length; >> >> __recv_frame(husb, >> _urb->type, >> urb->transfer_buffer + urb->iso_frame_desc[i].offset, >> len); >> 4. Logging "SCO packet for unknown connection handle" error only once >> for 100 errors. This will give more change to queue a URB as >> follows(hci_core.c:hci_scodata_packet function): >> hdev->stat.err_rx++; >> if(!(hdev->stat.err_rx % 100)) >> { >> BT_ERR("%s 100 SCO packets for unknown connection >> handles",hdev->name); } >> >> >> I must say that I did not try with latest Linux kernel however I >> could not see any code change regarding this functionality. Hope this >> will help. >> >> Regards, >> Dev >> >> >> -----Original Message----- >> From: linux-bluetooth-owner@xxxxxxxxxxxxxxx >> [mailto:linux-bluetooth-owner@xxxxxxxxxxxxxxx] On Behalf Of nirav >> rabara >> Sent: Wednesday, February 03, 2010 10:21 AM >> To: Gustavo F. Padovan >> Cc: linux-bluetooth@xxxxxxxxxxxxxxx >> Subject: Re: Kernel panic when SCO connection >> >> - Show quoted text - >> On Tue, Feb 2, 2010 at 10:46 PM, Gustavo F. Padovan >> <padovan@xxxxxxxxxxxxxx> wrote: >>> Hi Nirav, >>> >>> * nirav rabara <niravrabara@xxxxxxxxx> [2010-02-02 22:28:53 +0530]: >>> >>>> Hi, >>>> When I try to connect SCO socket, Kernel getting crash. >>>> Linux kernel - 2.6.22 >>>> Bluez - 4.58 >>> >>> Please try a 2.6.33 kernel and tell us if the bug still happens. >>> >>>> >>>> error message, >>>> __tx_submit:hci0 tx submit failed urb c0552c14 type 3 err -19 >>>> >>>> sometimes in connection is showing error while connection as below, >>>> hci_acldata_packet:hci0 ACL packet data for unknown connection >>>> handler 2 >>>> >>>> It would be really appreciable if somebody put some on light on >>>> this >> >>>> issue, OR suggest me any patch or documentation. >>>> >>>> -- >>>> With Regards, >>>> Nirav Rabara >>>> -- >>>> To unsubscribe from this list: send the line "unsubscribe >>>> linux-bluetooth" in the body of a message to >>>> majordomo@xxxxxxxxxxxxxxx More majordomo info at >>>> http://vger.kernel.org/majordomo-info.html >>> >>> -- >>> Gustavo F. Padovan >>> http://padovan.org >>> >>> ProFUSION embedded systems - http://profusion.mobi >>> >> >> Hi Gustavo, >> >> Thanks for your suggestion, but I am using bluez 4.58 on ATMEL >> AT91SAM9263, no patch available for the newer kernel 2.6.33 . Patches >> related to my board only available up to 2.6.30. >> >> It would be a great help if suggest me any alternet for this issue. >> OR any patches for the same problem as i mentioned for 2.6.22. >> >> >> -- >> With Regards, >> Nirav Rabara >> -- >> To unsubscribe from this list: send the line "unsubscribe >> linux-bluetooth" in the body of a message to >> majordomo@xxxxxxxxxxxxxxx More majordomo info at >> http://vger.kernel.org/majordomo-info.html >> -- >> To unsubscribe from this list: send the line "unsubscribe >> linux-bluetooth" in the body of a message to >> majordomo@xxxxxxxxxxxxxxx More majordomo info at >> http://vger.kernel.org/majordomo-info.html >> > -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
