summaryrefslogtreecommitdiffstats
path: root/arch
diff options
context:
space:
mode:
authorPrashanth Prakash <pprakash@codeaurora.org>2017-01-26 11:08:32 -0700
committerCatalin Marinas <catalin.marinas@arm.com>2017-01-27 11:30:36 +0000
commit606f42265d384b9149bfb953c5dfc6d4710fef4c (patch)
treed9f4f42760984c6dabc2b4220bfc72652591a824 /arch
parent7a308bb3016f57e5be11a677d15b821536419d36 (diff)
downloadlinux-606f42265d384b9149bfb953c5dfc6d4710fef4c.tar.bz2
arm64: skip register_cpufreq_notifier on ACPI-based systems
On ACPI based systems where the topology is setup using the API store_cpu_topology, at the moment we do not have necessary code to parse cpu capacity and handle cpufreq notifier, thus resulting in a kernel panic. Stack: init_cpu_capacity_callback+0xb4/0x1c8 notifier_call_chain+0x5c/0xa0 __blocking_notifier_call_chain+0x58/0xa0 blocking_notifier_call_chain+0x3c/0x50 cpufreq_set_policy+0xe4/0x328 cpufreq_init_policy+0x80/0x100 cpufreq_online+0x418/0x710 cpufreq_add_dev+0x118/0x180 subsys_interface_register+0xa4/0xf8 cpufreq_register_driver+0x1c0/0x298 cppc_cpufreq_init+0xdc/0x1000 [cppc_cpufreq] do_one_initcall+0x5c/0x168 do_init_module+0x64/0x1e4 load_module+0x130c/0x14d0 SyS_finit_module+0x108/0x120 el0_svc_naked+0x24/0x28 Fixes: 7202bde8b7ae ("arm64: parse cpu capacity-dmips-mhz from DT") Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/arm64/kernel/topology.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c
index 23e9e13bd2aa..655e65f38f31 100644
--- a/arch/arm64/kernel/topology.c
+++ b/arch/arm64/kernel/topology.c
@@ -11,6 +11,7 @@
* for more details.
*/
+#include <linux/acpi.h>
#include <linux/cpu.h>
#include <linux/cpumask.h>
#include <linux/init.h>
@@ -209,7 +210,12 @@ static struct notifier_block init_cpu_capacity_notifier = {
static int __init register_cpufreq_notifier(void)
{
- if (cap_parsing_failed)
+ /*
+ * on ACPI-based systems we need to use the default cpu capacity
+ * until we have the necessary code to parse the cpu capacity, so
+ * skip registering cpufreq notifier.
+ */
+ if (!acpi_disabled || cap_parsing_failed)
return -EINVAL;
if (!alloc_cpumask_var(&cpus_to_visit, GFP_KERNEL)) {