[+cc linux-pci, Myron, Suravee, Kim, Aravind] On Thu, Mar 13, 2014 at 5:43 AM, Daniel J Blueman <daniel@xxxxxxxxxxxxx> wrote: > For systems with multiple servers and routed fabric, all northbridges get > assigned to the first server. Fix this by also using the node reported from > the PCI bus. For single-fabric systems, the northbriges are on PCI bus 0 > by definition, which are on NUMA node 0 by definition, so this is invarient > on most systems. > > Tested on fam10h and fam15h single and multi-fabric systems and candidate > for stable. I wish this had been cc'd to linux-pci. We're talking about a related change by Suravee there. In fact, we were hoping this quirk could be removed altogether. I don't understand what this quirk is doing. Normally we discover the NUMA node for a PCI host bridge via the ACPI _PXM method. The way _PXM works is that every PCI device in the hierarchy below the bridge inherits the same node number as the host bridge. I first thought this might be a workaround for a system that lacks _PXM, but I don't think that can be right, because you're only changing the node for a few devices, not the whole hierarchy. So I suspect the problem is more complicated, and maybe _PXM is insufficient to describe the topology? Are there subtrees that should have nodes different from the host bridge? I know this patch is already in v3.14-rc7, but I'd still like to understand it so we can do the right thing with Suravee's patch. Bjorn > Signed-off-by: Daniel J Blueman <daniel@xxxxxxxxxxxxx> > Acked-by: Steffen Persvold <sp@xxxxxxxxxxxxx> > --- > arch/x86/kernel/quirks.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c > index 04ee1e2..52dbf1e 100644 > --- a/arch/x86/kernel/quirks.c > +++ b/arch/x86/kernel/quirks.c > @@ -529,7 +529,7 @@ static void quirk_amd_nb_node(struct pci_dev *dev) > return; > > pci_read_config_dword(nb_ht, 0x60, &val); > - node = val & 7; > + node = pcibus_to_node(dev->bus) | (val & 7); > /* > * Some hardware may return an invalid node ID, > * so check it first: > -- > 1.8.3.2 > > -- > 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/ -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
