Julian Margetson <runaway@xxxxxxxx> writes: > On 12/18/2015 6:33 PM, Måns Rullgård wrote: >> Julian Margetson <runaway@xxxxxxxx> writes: >> >>> On 12/18/2015 1:18 PM, Måns Rullgård wrote: >>>> Julian Margetson <runaway@xxxxxxxx> writes: >>>> >>>>> On 12/18/2015 8:49 AM, Måns Rullgård wrote: >>>>>> Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> writes: >>>>>> >>>>>>>>> [ 5.206125] Unable to handle kernel paging request for data at >>>>>>>>> address 0x00000000 >>>>>>>>> [ 5.228546] Faulting instruction address: 0xc043a2c8 >>>>>>>>> [ 5.248577] Vector: 300 (Data Access) at [eddafae0] >>>>>>>>> [ 5.268658] pc: c043a2c8: sata_dwc_qc_issue+0xb8/0x204 >>>>>>>> Well, that's not good. Can you translate that address to a line of >>>>>>>> code? >>>>>>> Besides that, can you enable DYNAMIC_DEBUG in the config and append >>>>>>> 'dw_dmac_core.dyndbg dw_dmac.dyndbg' to the kernel cmdline? >>>>>> Enabling debug messages in the sata_dwc driver might also be informative. >>>>>> >>>>> Changed the sata-dwc to a module . >>>>> >>>>> [ 18.475140] sata-dwc 4bffd1000.sata: sata_dwc_qc_prep_by_tag: dma_dwc_xfer_setup returns NULL >>>>> [ 18.535698] sata-dwc 4bffd1000.sata: sata_dwc_qc_prep_by_tag: dma_dwc_xfer_setup returns NULL >>>> That's strange. The only way that can happen is if >>>> dmaengine_prep_slave_sg() return NULL, and that really shouldn't be >>>> happening. Did you turn on debug messages in dw_dma? You can enable >>>> some extra debug messages by adding "#define VERBOSE_DEBUG" at the top >>>> of drivers/dma/dw/core.c >>>> >>> [ 17.526173] sata-dwc 4bffd1000.sata: sata_dwc_qc_prep_by_tag: dma_dwc_xfer_setup returns NULL >>> [ 17.600124] sata-dwc 4bffd1000.sata: sata_dwc_qc_prep_by_tag: dma_dwc_xfer_setup returns NULL >>> [ 17.662978] sata-dwc 4bffd1000.sata: sata_dwc_qc_prep_by_tag: dma_dwc_xfer_setup returns NULL >> Could you post the entire kernel log? There might be important >> information before the errors start. >> > > > =~=~=~=~=~=~=~=~=~=~=~= PuTTY log 2015.12.18 15:01:48 =~=~=~=~=~=~=~=~=~=~=~= > [ 0.000000] Using Canyonlands machine description > [ 0.000000] Initializing cgroup subsys cpu > [ 0.000000] Linux version 4.4.0-rc5-Sam460ex (root@julian-VirtualBox) (gcc version 4.8.2 (Ubuntu 4.8.2-16ubuntu3) ) #8 PREEMPT Fri Dec 18 13:36:34 AST 2015 > [ 0.000000] Zone ranges: > [ 0.000000] DMA [mem 0x0000000000000000-0x000000002fffffff] > [ 0.000000] Normal empty > [ 0.000000] HighMem [mem 0x0000000030000000-0x000000007fffffff] > [ 0.000000] Movable zone start for each node > [ 0.000000] Early memory node ranges > [ 0.000000] node 0: [mem 0x0000000000000000-0x000000007fffffff] > [ 0.000000] Initmem setup node 0 [mem 0x0000000000000000-0x000000007fffffff] > [ 0.000000] MMU: Allocated 1088 bytes of context maps for 255 contexts > [ 0.000000] Built 1 zonelists in Zone order, mobility grouping on. Total pages: 522752 > [ 0.000000] Kernel command line: root=/dev/sda8 console=ttyS0,115200 console=tty0 dw_dmac_core.dyndbg dw_dmac.dyndbg [...] > [ 13.643415] systemd[1]: Mounted Configuration File System. > [ 17.526173] sata-dwc 4bffd1000.sata: sata_dwc_qc_prep_by_tag: dma_dwc_xfer_setup returns NULL > [ 17.600124] sata-dwc 4bffd1000.sata: sata_dwc_qc_prep_by_tag: dma_dwc_xfer_setup returns NULL > [ 17.662978] sata-dwc 4bffd1000.sata: sata_dwc_qc_prep_by_tag: dma_dwc_xfer_setup returns NULL This log is weird. The sata_dwc_probe() function prints several things (one using dev_notice()), for instance this: /* Read the ID and Version Registers */ idr = in_le32(&hsdev->sata_dwc_regs->idr); versionr = in_le32(&hsdev->sata_dwc_regs->versionr); dev_notice(&ofdev->dev, "id %d, controller version %c.%c%c\n", idr, ver[0], ver[1], ver[2]); The dw_dma_probe() function also prints a line: dev_info(chip->dev, "DesignWare DMA Controller, %d channels\n", pdata->nr_channels); These messages are nowhere to be seen in your log, nor are numerous others that really must appear before before sata_dwc_qc_prep_by_tag() can be called. I'd like to note that the driver works on my Sigma Designs based system using a different DMA controller, so it's not completely broken. The DMA driver could still be faulty, but that still doesn't explain the missing kernel messages. -- Måns Rullgård -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
