Messages in this thread |  | | Date | Fri, 14 Oct 2016 10:05:24 +0200 | From | Andrew Jones <> | Subject | Re: aarch64 ACPI boot regressed by commit 7ba5f605f3a0 ("arm64/numa: remove the limitation that cpu0 must bind to node0") |
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On Fri, Oct 14, 2016 at 12:50:29AM +0200, Laszlo Ersek wrote: > (4) Analysis (well, a lame attempt at that, because I have zero > familiarity with this code). Let me quote the patch: > > > commit 7ba5f605f3a0d9495aad539eeb8346d726dfc183 > > Author: Zhen Lei <thunder.leizhen@huawei.com> > > Date: Thu Sep 1 14:55:04 2016 +0800 > > > > arm64/numa: remove the limitation that cpu0 must bind to node0 > > > > 1. Remove the old binding code. > > 2. Read the nid of cpu0 from dts. > > 3. Fallback the nid of cpu0 to 0 when numa=off is set in bootargs. > > > > Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com> > > Signed-off-by: Will Deacon <will.deacon@arm.com> > > > > diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c > > index c3c08368a685..8b048e6ec34a 100644 > > --- a/arch/arm64/kernel/smp.c > > +++ b/arch/arm64/kernel/smp.c > > @@ -624,6 +624,7 @@ static void __init of_parse_and_init_cpus(void) > > } > > > > bootcpu_valid = true; > > + early_map_cpu_to_node(0, of_node_to_nid(dn)); > > > > /* > > * cpu_logical_map has already been > > diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c > > index 0a15f010b64a..778a985c8a70 100644 > > --- a/arch/arm64/mm/numa.c > > +++ b/arch/arm64/mm/numa.c > > @@ -116,16 +116,24 @@ static void __init setup_node_to_cpumask_map(void) > > */ > > void numa_store_cpu_info(unsigned int cpu) > > { > > - map_cpu_to_node(cpu, numa_off ? 0 : cpu_to_node_map[cpu]); > > + map_cpu_to_node(cpu, cpu_to_node_map[cpu]); > > } > > > > void __init early_map_cpu_to_node(unsigned int cpu, int nid) > > { > > /* fallback to node 0 */ > > - if (nid < 0 || nid >= MAX_NUMNODES) > > + if (nid < 0 || nid >= MAX_NUMNODES || numa_off) > > nid = 0;
The ACPI equivalent code must be missing (at least) the above, because, even with DT, mach-virt won't have cpu to node mappings unless numa is configured on the command line. Can you try adding something like
-m 512 -smp 4 \ -numa node,mem=256M,cpus=0-1,nodeid=0 \ -numa node,mem=256M,cpus=2-3,nodeid=1
to your QEMU command line? Then when you boot with ACPI you'll get a SRAT. If that works, then we're just missing the "no SRAT, nid = 0" code (that should have been added with this patch)
Thanks, drew
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