diff options
| author | Guixiong Wei <weiguixiong@bytedance.com> | 2026-06-02 10:07:52 +0800 |
|---|---|---|
| committer | Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> | 2026-06-10 14:51:55 +0300 |
| commit | 6b63520ed14b17bbe9c2103debbd2152dde1fba3 (patch) | |
| tree | 65d10b358d4174c6409005742fd20793825d83df | |
| parent | c085d82613d5618814b84406c8b2d64f1bc305e7 (diff) | |
platform/x86/intel-uncore-freq: Fix current_freq_khz after CPU hotplug
When the last CPU of a legacy uncore die goes offline,
uncore_freq_remove_die_entry() clears control_cpu. During CPU hotplug
re-add, uncore_freq_add_entry() still populates sysfs attributes before
assigning the new control CPU. As a result, the current frequency read
returns -ENXIO and current_freq_khz is omitted from the recreated sysfs
group.
Assign control_cpu before the initial read paths and before
create_attr_group() so sysfs recreation uses the new online CPU. If
sysfs creation fails, restore control_cpu to -1 to keep the error path
state consistent.
Fixes: 4d73c6772ab7 ("platform/x86: intel-uncore-freq: Conditionally create attribute for read frequency")
Cc: stable@vger.kernel.org
Signed-off-by: Guixiong Wei <weiguixiong@bytedance.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Link: https://patch.msgid.link/20260602020752.3126-1-weiguixiong@bytedance.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
| -rw-r--r-- | drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.c b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.c index 3b554418a7a3..4bcafedf68ef 100644 --- a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.c +++ b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.c @@ -285,15 +285,20 @@ int uncore_freq_add_entry(struct uncore_data *data, int cpu) data->package_id, data->die_id); } + /* + * Set the control CPU before any read path so entry recreation after CPU + * hotplug can populate read-only attributes from the new online CPU. + */ + data->control_cpu = cpu; uncore_read(data, &data->initial_min_freq_khz, UNCORE_INDEX_MIN_FREQ); uncore_read(data, &data->initial_max_freq_khz, UNCORE_INDEX_MAX_FREQ); ret = create_attr_group(data, data->name); if (ret) { + data->control_cpu = -1; if (data->domain_id != UNCORE_DOMAIN_ID_INVALID) ida_free(&intel_uncore_ida, data->seqnum_id); } else { - data->control_cpu = cpu; data->valid = true; } |