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author | Sven Schnelle <svens@linux.ibm.com> | 2021-08-27 20:21:05 +0200 |
---|---|---|
committer | Heiko Carstens <hca@linux.ibm.com> | 2021-09-07 13:38:41 +0200 |
commit | a052096bdd6809eeab809202726634d1ac975aa1 (patch) | |
tree | 80e72fe5fe0a406816ca467958870dd0f8dc5bec /arch/s390/kernel/topology.c | |
parent | 88b604263f3d6eedae0b1c2c3bbd602d1e2e8775 (diff) | |
download | linux-stable-a052096bdd6809eeab809202726634d1ac975aa1.tar.gz linux-stable-a052096bdd6809eeab809202726634d1ac975aa1.tar.bz2 linux-stable-a052096bdd6809eeab809202726634d1ac975aa1.zip |
s390/topology: fix topology information when calling cpu hotplug notifiers
The cpu hotplug notifiers are called without updating the core/thread
masks when a new CPU is added. This causes problems with code setting
up data structures in a cpu hotplug notifier, and relying on that later
in normal code.
This caused a crash in the new core scheduling code (SCHED_CORE),
where rq->core was set up in a notifier depending on cpu masks.
To fix this, add a cpu_setup_mask which is used in update_cpu_masks()
instead of the cpu_online_mask to determine whether the cpu masks should
be set for a certain cpu. Also move update_cpu_masks() to update the
masks before calling notify_cpu_starting() so that the notifiers are
seeing the updated masks.
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Cc: <stable@vger.kernel.org>
[hca@linux.ibm.com: get rid of cpu_online_mask handling]
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Diffstat (limited to 'arch/s390/kernel/topology.c')
-rw-r--r-- | arch/s390/kernel/topology.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c index d2458a29618f..58f8291950cb 100644 --- a/arch/s390/kernel/topology.c +++ b/arch/s390/kernel/topology.c @@ -67,7 +67,7 @@ static void cpu_group_map(cpumask_t *dst, struct mask_info *info, unsigned int c static cpumask_t mask; cpumask_clear(&mask); - if (!cpu_online(cpu)) + if (!cpumask_test_cpu(cpu, &cpu_setup_mask)) goto out; cpumask_set_cpu(cpu, &mask); switch (topology_mode) { @@ -88,7 +88,7 @@ static void cpu_group_map(cpumask_t *dst, struct mask_info *info, unsigned int c case TOPOLOGY_MODE_SINGLE: break; } - cpumask_and(&mask, &mask, cpu_online_mask); + cpumask_and(&mask, &mask, &cpu_setup_mask); out: cpumask_copy(dst, &mask); } @@ -99,16 +99,16 @@ static void cpu_thread_map(cpumask_t *dst, unsigned int cpu) int i; cpumask_clear(&mask); - if (!cpu_online(cpu)) + if (!cpumask_test_cpu(cpu, &cpu_setup_mask)) goto out; cpumask_set_cpu(cpu, &mask); if (topology_mode != TOPOLOGY_MODE_HW) goto out; cpu -= cpu % (smp_cpu_mtid + 1); - for (i = 0; i <= smp_cpu_mtid; i++) - if (cpu_present(cpu + i)) + for (i = 0; i <= smp_cpu_mtid; i++) { + if (cpumask_test_cpu(cpu + i, &cpu_setup_mask)) cpumask_set_cpu(cpu + i, &mask); - cpumask_and(&mask, &mask, cpu_online_mask); + } out: cpumask_copy(dst, &mask); } @@ -569,6 +569,7 @@ void __init topology_init_early(void) alloc_masks(info, &book_info, 2); alloc_masks(info, &drawer_info, 3); out: + cpumask_set_cpu(0, &cpu_setup_mask); __arch_update_cpu_topology(); __arch_update_dedicated_flag(NULL); } |