path: root/arch
diff options
authorAtish Patra <atish.patra@oracle.com>2016-09-15 14:54:40 -0600
committerDavid S. Miller <davem@davemloft.net>2016-09-28 08:24:02 -0700
commit9b2f753ec23710aa32c0d837d2499db92fe9115b (patch)
tree3fe8894d45a41028a16506e98286c974e954942a /arch
parent1e953d846ac015fbfcf09c857e8f893924cb629c (diff)
sparc64: Fix cpu_possible_mask if nr_cpus is set
If kernel boot parameter nr_cpus is set, it should define the number of CPUs that can ever be available in the system i.e. cpu_possible_mask. setup_nr_cpu_ids() overrides the nr_cpu_ids based on the cpu_possible_mask during kernel initialization. If cpu_possible_mask is not set based on the nr_cpus value, earlier part of the kernel would be initialized using nr_cpus value leading to a kernel crash. Set cpu_possible_mask based on nr_cpus value. Thus setup_nr_cpu_ids() becomes redundant and does not corrupt nr_cpu_ids value. Signed-off-by: Atish Patra <atish.patra@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Vijay Kumar <vijay.ac.kumar@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch')
3 files changed, 16 insertions, 0 deletions
diff --git a/arch/sparc/include/asm/smp_64.h b/arch/sparc/include/asm/smp_64.h
index 26d9e7726867..87b05751955a 100644
--- a/arch/sparc/include/asm/smp_64.h
+++ b/arch/sparc/include/asm/smp_64.h
@@ -43,6 +43,7 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask);
int hard_smp_processor_id(void);
#define raw_smp_processor_id() (current_thread_info()->cpu)
+void smp_fill_in_cpu_possible_map(void);
void smp_fill_in_sib_core_maps(void);
void cpu_play_dead(void);
diff --git a/arch/sparc/kernel/setup_64.c b/arch/sparc/kernel/setup_64.c
index 599f1207eed2..f32cfe83dfd1 100644
--- a/arch/sparc/kernel/setup_64.c
+++ b/arch/sparc/kernel/setup_64.c
@@ -650,6 +650,7 @@ void __init setup_arch(char **cmdline_p)
+ smp_fill_in_cpu_possible_map();
extern int stop_a_enabled;
diff --git a/arch/sparc/kernel/smp_64.c b/arch/sparc/kernel/smp_64.c
index 8a6151a628ce..d3035ba6cd31 100644
--- a/arch/sparc/kernel/smp_64.c
+++ b/arch/sparc/kernel/smp_64.c
@@ -1227,6 +1227,20 @@ void __init smp_setup_processor_id(void)
xcall_deliver_impl = hypervisor_xcall_deliver;
+void __init smp_fill_in_cpu_possible_map(void)
+ int possible_cpus = num_possible_cpus();
+ int i;
+ if (possible_cpus > nr_cpu_ids)
+ possible_cpus = nr_cpu_ids;
+ for (i = 0; i < possible_cpus; i++)
+ set_cpu_possible(i, true);
+ for (; i < NR_CPUS; i++)
+ set_cpu_possible(i, false);
void smp_fill_in_sib_core_maps(void)
unsigned int i;