Bug 72051
| Summary: | Failed to correctly detect device numa_node information on AMD systems | ||
|---|---|---|---|
| Product: | Drivers | Reporter: | Suravee Suthikulpanit (suravee.suthikulpanit) |
| Component: | PCI | Assignee: | drivers_pci (drivers_pci) |
| Status: | RESOLVED CODE_FIX | ||
| Severity: | normal | CC: | aaron.lu, bjorn |
| Priority: | P1 | ||
| Hardware: | x86-64 | ||
| OS: | Linux | ||
| Kernel Version: | 3.14-rc4 | Subsystem: | |
| Regression: | No | Bisected commit-id: | |
| Attachments: |
Dump from SRAT table
Dump from SLIT table Dump from DSDT table |
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Created attachment 129331 [details]
Dump from SRAT table
Created attachment 129341 [details]
Dump from SLIT table
Created attachment 129351 [details]
Dump from DSDT table
Resolved by http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=94d4bb5b13978127d12860bc6b7071a784144e2f which will appear in v3.16-rc1. |
This bug affects AMD family 12h and newer. The device numa_node information in the sysfs for each PCI device (e.g. /devices/pci0000:50/0000:50:00.2/numa_node) is showing value -1. In file arch/x86/pci/acpi.c, in function pci_acpi_scan_root(), it is queries the node information as following: #ifdef CONFIG_ACPI_NUMA pxm = acpi_get_pxm(device->handle); if (pxm >= 0) node = pxm_to_node(pxm); if (node != -1) set_mp_bus_to_node(busnum, node); else #endif node = get_mp_bus_to_node(busnum); In this case, I see that the acpi_get_pxm() returns -1. Therefore, it falls back to using the node information in mp_bus_to_node[]. For AMD systems, the arch/x86/pci/amd_bus.c only probe the hostbridge for family10h and 11h, and showing the correct numa_node information. For the newer systems, it does not fill the mp_bus_to_node[], and result in the value -1. Please refer to the following email thread for more information: http://marc.info/?l=linux-kernel&m=139405365524526&w=2