Re: [BUG] Bisected Problem with LSI PCI FC Adapter

From: Bjorn Helgaas
Date: Thu Sep 11 2014 - 13:31:03 EST


[+cc linux-pci]


On Thu, Sep 11, 2014 at 7:43 AM, Dirk Gouders <dirk@xxxxxxxxxxx> wrote:
> Andreas Noever <andreas.noever@xxxxxxxxx> writes:
>
>> On Wed, Sep 3, 2014 at 2:47 PM, Dirk Gouders <dirk@xxxxxxxxxxx> wrote:
>>> Andreas Noever <andreas.noever@xxxxxxxxx> writes:
>>>
>>>> On Wed, Sep 3, 2014 at 12:57 PM, Dirk Gouders <dirk@xxxxxxxxxxx> wrote:
>>>>> On a Tyan VX50 (B4985) I ran into problems when updating the kernel: the
>>>>> PCI FC Adapter is no longer recognized.
>>>>
>>>> Can you provide the output of lspci -vvv and the output of dmesg from
>>>> a working boot? Which card is the one that is not recognized?
>>>
>>> Sure, the card that disappeared is:
>>>
>>> 0a:00.0 Fibre Channel: LSI Logic / Symbios Logic FC949ES Fibre Channel Adapter (rev 02)
>>
>> As far as I can tell the following is happening:
>> The root bus resource window (advertised by the bios?) is to small:
>> pci_bus 0000:00: root bus resource [bus 00-07]
>> Previously we didn't really care. There is a resource conflict but we
>> ignored it:
>> pci_bus 0000:0a: busn_res: can not insert [bus 0a] under [bus 00-07]
>> (conflicts with (null) [bus 00-07])
>> With the patch we mark the bridge as broken and reassign the bus to 06:
>> pci 0000:00:0e.0: bridge configuration invalid ([bus 0a-0a]), reconfiguring
>> pci 0000:00:0e.0: PCI bridge to [bus 06-07]
>> pci 0000:00:0e.0: bridge window [io 0x3000-0x3fff]
>> pci 0000:00:0e.0: bridge window [mem 0xd4200000-0xd42fffff]
>> pci_bus 0000:06: busn_res: [bus 06-07] end is updated to 06
>>
>> We still scan for children but nothing shows up ("PCI bridge to" is
>> from pci_scan_child_bus -> pcibios_fixup_bus -> pci_read_bridge_base,
>> after pci_scan_slot). I have no idea why the device does not respond.
>
> Andreas,
>
> I found an identical FC Adapter here (backup) and was hoping to be able to
> setup a test-machine where I can easily reproduce the problem, but
> on that machine, the problem does not occur. So, I have to stick to the
> busy machine for testing and diagnosis.
>
> What I further did was rebooting the problematic machine and
> enabling more messages (dyndbg="file drivers/pci/* +pf") with
> the working and problematic kernel; the dmesg output is attached.

Dirk,

Thanks for following up on this. It had fallen off my radar, so I
opened https://bugzilla.kernel.org/show_bug.cgi?id=84281 to make sure
I don't forget again. Please continue the debug discussion here in
email.

Bjorn
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/