At 09/13/2012 01:18 AM, Vasilis Liaskovitis Wrote: > Hi, > > On Wed, Sep 12, 2012 at 01:20:28PM +0800, Wen Congyang wrote: >>> >>> On Mon, Sep 10, 2012 at 10:01:44AM +0800, Wen Congyang wrote: >>>> At 09/10/2012 09:46 AM, Yasuaki Ishimatsu Wrote: >>>>> How do you test the patch? As Andrew says, for hot-removing memory, >>>>> we need a particular hardware. I think so too. So many people may want >>>>> to know how to test the patch. >>>>> If we apply following patch to kvm guest, can we hot-remove memory on >>>>> kvm guest? >>>>> >>>>> http://lists.gnu.org/archive/html/qemu-devel/2012-07/msg01389.html >>>> >>>> Yes, if we apply this patchset, we can test hot-remove memory on kvm guest. >>>> But that patchset doesn't implement _PS3, so there is some restriction. >>> >>> the following repos contain the patchset above, plus 2 more patches that add >>> PS3 support to the dimm devices in qemu/seabios: >>> >>> https://github.com/vliaskov/seabios/commits/memhp-v2 >>> https://github.com/vliaskov/qemu-kvm/commits/memhp-v2 >>> >>> I have not posted the PS3 patches yet in the qemu list, but will post them >>> soon for v3 of the memory hotplug series. If you have issues testing, let me >>> know. >> >> Hmm, seabios doesn't support ACPI table SLIT. We can specify node it for dimm >> device, so I think we should support SLIT in seabios. Otherwise we may meet >> the following kernel messages: >> [ 325.016769] init_memory_mapping: [mem 0x40000000-0x5fffffff] >> [ 325.018060] [mem 0x40000000-0x5fffffff] page 2M >> [ 325.019168] [ffffea0001000000-ffffea00011fffff] potential offnode page_structs >> [ 325.024172] [ffffea0001200000-ffffea00013fffff] potential offnode page_structs >> [ 325.028596] [ffffea0001400000-ffffea00017fffff] PMD -> [ffff880035000000-ffff8800353fffff] on node 1 >> [ 325.031775] [ffffea0001600000-ffffea00017fffff] potential offnode page_structs >> >> Do you have plan to do it? > thanks for testing. > > commit 5294828 from https://github.com/vliaskov/seabios/commits/memhp-v2 > implements a SLIT table for the given numa nodes. Hmm, why do you set node_distance(i, j) to REMOTE_DISTANCE if i != j? > > However I am not sure the SLIT is the problem. The kernel builds a default > numa_distance table in arch/x86/mm/numa.c: numa_alloc_distance(). If the BIOS > doesn't present a SLIT, this should take effect (numactl --hardware should > report this table) If the BIOS doesn't present a SLIT, numa_distance_cnt is set to 0 in the function numa_reset_distance(). So node_distance(i, j) is REMOTE_DISTANCE(i != j). > > Do you have more details on how to reproduce the warning? e.g. how many dimms > are present in the system? Does this happen on the first dimm hot-plugged? > Are all SRAT entries parsed correctly at boot-time or do you see any other > warnings at boot-time? I can't reproduce it again. IIRC, I only do the following things: hotplug a memory device, online the pages, offline the pages and hot remove the memory device. Thanks Wen Congyang > > I 'll investigate a bit more and report back. > > thanks, > > - Vasilis > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
