From: Perry Yuan perry.yuan@amd.com
commit 4f3085f87b51a551a0647f218d4f324796ecb703 upstream.
In the amd_pstate_adjust_perf(), there is one cpufreq_cpu_get() call to increase increments the kobject reference count of policy and make it as busy. Therefore, a corresponding call to cpufreq_cpu_put() is needed to decrement the kobject reference count back, it will resolve the kernel hang issue when unregistering the amd-pstate driver and register the `amd_pstate_epp` driver instance.
Fixes: 1d215f0319 ("cpufreq: amd-pstate: Add fast switch function for AMD P-State") Acked-by: Huang Rui ray.huang@amd.com Reviewed-by: Mario Limonciello mario.limonciello@amd.com Tested-by: Wyes Karny wyes.karny@amd.com Signed-off-by: Perry Yuan perry.yuan@amd.com Cc: 5.17+ stable@vger.kernel.org # 5.17+ Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/cpufreq/amd-pstate.c | 1 + 1 file changed, 1 insertion(+)
--- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -307,6 +307,7 @@ static void amd_pstate_adjust_perf(unsig max_perf = min_perf;
amd_pstate_update(cpudata, min_perf, des_perf, max_perf, true); + cpufreq_cpu_put(policy); }
static int amd_get_min_freq(struct amd_cpudata *cpudata)