Re: [PATCH] PCI/shpchp: fix a bus speed issue on hotplug

[Bjorn Helgaas]

On Thu, May 1, 2014 at 12:57 PM, Marcel Apfelbaum
<marcel.apfelbaum@xxxxxxxxx> wrote:
> On Thu, 2014-05-01 at 21:13 +0300, Marcel Apfelbaum wrote:
>> On Thu, 2014-05-01 at 12:02 -0600, Bjorn Helgaas wrote:
>> > On Thu, May 1, 2014 at 8:35 AM, Marcel Apfelbaum <marcel.a@xxxxxxxxxx> wrote:
>> > > When a board is added, the shpchp driver checks if there
>> > > is a mismatch between the bridge's adapter and the bus speed.
>> > > If there is, it sets the subordinate speed (if there is no device on it).
>> > >
>> > > However, it takes the reference of the board speed from the primary bus
>> > > and not from the subordinate. If the primary bus is PCI and not PCIX/PCIe,
>> > > its speed is not updated and remains 0xff. As a result hotplug fails
>> > > with error: "Speed of bus ff and adapter 0 mismatch".
>> >
>> > It'd be cool to have a bugzilla for this with lspci and dmesg output.
>> > I'll also have to check the other hotplug drivers for similar issues,
>> > unless you've already done that.
>> I'll open a BZ with the details, sure.
> Done: https://bugzilla.kernel.org/show_bug.cgi?id=75251
> If you need further details, please let me know.

Thanks.  Would you mind attaching the "lspci -vv" output?  That should
show more details, including the information used to compute the bus
speed.

Also, you checked the "regression" box.  Can you confirm that and
identify a known-working kernel?  If we know which kernels are broken,
we can potentially mark the fix to be backported to them.

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/