From 3e8db2246b434c6b18a6a9f09904038bddcf76c7 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 18 Mar 2016 17:20:30 +0100 Subject: x86/topology: Use total_cpus not nr_cpu_ids for logical packages nr_cpu_ids can be limited on the command line via nr_cpus=. That can break the logical package management because it results in a smaller number of packages, but the cpus to online are occupying the full package space as the hyper threads are enumerated after the physical cores typically. total_cpus is the real possible cpu space not limited by nr_cpus command line and gives us the proper number of packages. Reported-by: Mike Galbraith Fixes: 1f12e32f4cd5 ("x86/topology: Create logical package id") Signed-off-by: Thomas Gleixner Cc: Xiong Zhou Cc: Ingo Molnar Cc: Borislav Petkov Cc: Andreas Herrmann Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1603181254330.3978@nanos diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 81e6a43..b2c99f8 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -325,9 +325,14 @@ static void __init smp_init_package_map(void) * By not including this we'll sometimes over-estimate the number of * logical packages by the amount of !present siblings, but this is * still better than MAX_LOCAL_APIC. + * + * We use total_cpus not nr_cpu_ids because nr_cpu_ids can be limited + * on the command line leading to a similar issue as the HT disable + * problem because the hyperthreads are usually enumerated after the + * primary cores. */ ncpus = boot_cpu_data.x86_max_cores; - __max_logical_packages = DIV_ROUND_UP(nr_cpu_ids, ncpus); + __max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus); /* * Possibly larger than what we need as the number of apic ids per -- cgit v0.10.2