Re: Null Pointer BUG in uhci_hcd

From: Michael S. Zick
Date: Tue Jul 07 2009 - 15:51:22 EST


On Tue July 7 2009, Alan Stern wrote:
> On Tue, 7 Jul 2009, Michael S. Zick wrote:
>
> > On Tue July 7 2009, Alan Stern wrote:
> > > On Tue, 7 Jul 2009, Michael S. Zick wrote:
> > >
> > > > > It looks like there's a serious problem in your UHCI hardware.
> > > > > According to the log you posted, it's not working at all.
> > > > >
> > > >
> > > > I am using the x86-generic drivers - -
> > >
> > > Not a problem with the drivers, a problem in the hardware.
> > >
> >
> > Or hardware that works as the manufacturer intended, but differently
> > than expected. Same difference as "broken" when compared to "standard".
>
> No, hardware that doesn't work at all. As in "all reads return
> 0xffffffff" -- that's just a guess but something like it would account
> for what you saw.
>
> For more information enable CONFIG_USB_DEBUG and CONFIG_DEBUG_FS, then
> see what's sitting in the usb/uhci/* files in debugfs.
>

Will add that to my list - -
I need to do that to find/fix that error path message flood loop in ehci anyway.

Mike
> > Let me see if I can find it again;
> > 1106:3038 translates to: PCI_DEVICE_ID_VIA_82C586_2
> > 1106:3104 translates to: PCI_DEVICE_ID_VIA_8235_USB_2
> >
> > The first appears in (this device is the UHCI hub in the CX700 chipset):
> > arch/powerpc/platforms/85xx/mpc85xx_cds.c: case PCI_DEVICE_ID_VIA_82C586_2:
> > arch/mips/pci/fixup-lm2e.c:DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C586_2,
> > include/linux/pci_ids.h:#define PCI_DEVICE_ID_VIA_82C586_2 0x3038
>
> Those are simple interrupt routing fixups. Not related.
>
> > The second appears in:
> > include/linux/pci_ids.h:#define PCI_DEVICE_ID_VIA_8235_USB_2 0x3104
> > <Hmm... Dead? Not used? Never used? Source padding?>
>
> Probably never used.
>
> Alan Stern
>
>
>


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