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Revert "cpufreq: intel_pstate: Process HWP Guaranteed change notification"

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Revert commit d0e936adbd22 ("cpufreq: intel_pstate: Process HWP
Guaranteed change notification"), because it causes a NULL pointer
dereference to occur on Lenovo X1 gen9 laptops due to an HWP
guaranteed performance change interrupt arriving prematurely.

This feature will be revisited in the next cycle.

Reported-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Rafael J. Wysocki 2021-09-07 15:32:48 +02:00
parent 4bf8e58211
commit dd7c46d6e5
1 changed files with 0 additions and 39 deletions
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39
drivers/cpufreq/intel_pstate.c
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@ -32,7 +32,6 @@
#include <asm/cpu_device_id.h>
#include <asm/cpufeature.h>
#include <asm/intel-family.h>
#include "../drivers/thermal/intel/thermal_interrupt.h"
#define INTEL_PSTATE_SAMPLING_INTERVAL (10 * NSEC_PER_MSEC)
@ -220,7 +219,6 @@ struct global_params {
* @sched_flags: Store scheduler flags for possible cross CPU update
* @hwp_boost_min: Last HWP boosted min performance
* @suspended: Whether or not the driver has been suspended.
* @hwp_notify_work: workqueue for HWP notifications.
*
* This structure stores per CPU instance data for all CPUs.
*/
@ -259,7 +257,6 @@ struct cpudata {
unsigned int sched_flags;
u32 hwp_boost_min;
bool suspended;
struct delayed_work hwp_notify_work;
};
static struct cpudata **all_cpu_data;
@ -1628,40 +1625,6 @@ static void intel_pstate_sysfs_hide_hwp_dynamic_boost(void)
/************************** sysfs end ************************/
static void intel_pstate_notify_work(struct work_struct *work)
{
mutex_lock(&intel_pstate_driver_lock);
cpufreq_update_policy(smp_processor_id());
wrmsrl(MSR_HWP_STATUS, 0);
mutex_unlock(&intel_pstate_driver_lock);
}
void notify_hwp_interrupt(void)
{
unsigned int this_cpu = smp_processor_id();
struct cpudata *cpudata;
u64 value;
if (!hwp_active || !boot_cpu_has(X86_FEATURE_HWP_NOTIFY))
return;
rdmsrl(MSR_HWP_STATUS, value);
if (!(value & 0x01))
return;
cpudata = all_cpu_data[this_cpu];
schedule_delayed_work_on(this_cpu, &cpudata->hwp_notify_work, msecs_to_jiffies(10));
}
static void intel_pstate_enable_hwp_interrupt(struct cpudata *cpudata)
{
/* Enable HWP notification interrupt for guaranteed performance change */
if (boot_cpu_has(X86_FEATURE_HWP_NOTIFY)) {
INIT_DELAYED_WORK(&cpudata->hwp_notify_work, intel_pstate_notify_work);
wrmsrl_on_cpu(cpudata->cpu, MSR_HWP_INTERRUPT, 0x01);
}
}
static void intel_pstate_hwp_enable(struct cpudata *cpudata)
{
/* First disable HWP notification interrupt as we don't process them */
@ -1671,8 +1634,6 @@ static void intel_pstate_hwp_enable(struct cpudata *cpudata)
wrmsrl_on_cpu(cpudata->cpu, MSR_PM_ENABLE, 0x1);
if (cpudata->epp_default == -EINVAL)
cpudata->epp_default = intel_pstate_get_epp(cpudata, 0);
intel_pstate_enable_hwp_interrupt(cpudata);
}
static int atom_get_min_pstate(void)