From b4b4c13e3bb21e3c5f193b395dbb9c1a1202f399 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 2 Dec 2009 14:09:16 +1030 Subject: sched: Fix isolcpus boot option commit bdddd2963c0264c56f18043f6fa829d3c1d3d1c0 upstream. Anton Blanchard wrote: > We allocate and zero cpu_isolated_map after the isolcpus > __setup option has run. This means cpu_isolated_map always > ends up empty and if CPUMASK_OFFSTACK is enabled we write to a > cpumask that hasn't been allocated. I introduced this regression in 49557e620339cb13 (sched: Fix boot crash by zalloc()ing most of the cpu masks). Use the bootmem allocator if they set isolcpus=, otherwise allocate and zero like normal. Reported-by: Anton Blanchard Signed-off-by: Rusty Russell Cc: peterz@infradead.org Cc: Linus Torvalds LKML-Reference: <200912021409.17013.rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar Tested-by: Anton Blanchard Signed-off-by: Greg Kroah-Hartman --- kernel/sched.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/kernel/sched.c b/kernel/sched.c index 4f675e4c7d5d..81ede13d2238 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -7945,6 +7945,7 @@ static cpumask_var_t cpu_isolated_map; /* Setup the mask of cpus configured for isolated domains */ static int __init isolated_cpu_setup(char *str) { + alloc_bootmem_cpumask_var(&cpu_isolated_map); cpulist_parse(str, cpu_isolated_map); return 1; } @@ -9389,7 +9390,9 @@ void __init sched_init(void) zalloc_cpumask_var(&nohz.cpu_mask, GFP_NOWAIT); alloc_cpumask_var(&nohz.ilb_grp_nohz_mask, GFP_NOWAIT); #endif - zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT); + /* May be allocated at isolcpus cmdline parse time */ + if (cpu_isolated_map == NULL) + zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT); #endif /* SMP */ perf_counter_init(); -- cgit v1.2.3