6.6-stable review patch. If anyone has any objections, please let me know.
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From: Shouye Liu shouyeliu@tencent.com
commit 8d6955ed76e8a47115f2ea1d9c263ee6f505d737 upstream.
In certain situations, the sysfs for uncore may not be present when all CPUs in a package are offlined and then brought back online after boot.
This issue can occur if there is an error in adding the sysfs entry due to a memory allocation failure. Retrying to bring the CPUs online will not resolve the issue, as the uncore_cpu_mask is already set for the package before the failure condition occurs.
This issue does not occur if the failure happens during module initialization, as the module will fail to load in the event of any error.
To address this, ensure that the uncore_cpu_mask is not set until the successful return of uncore_freq_add_entry().
Fixes: dbce412a7733 ("platform/x86/intel-uncore-freq: Split common and enumeration part") Signed-off-by: Shouye Liu shouyeliu@tencent.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250417032321.75580-1-shouyeliu@gmail.com Reviewed-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/platform/x86/intel/uncore-frequency/uncore-frequency.c | 13 ++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
--- a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency.c +++ b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency.c @@ -121,15 +121,13 @@ static int uncore_event_cpu_online(unsig { struct uncore_data *data; int target; + int ret;
/* Check if there is an online cpu in the package for uncore MSR */ target = cpumask_any_and(&uncore_cpu_mask, topology_die_cpumask(cpu)); if (target < nr_cpu_ids) return 0;
- /* Use this CPU on this die as a control CPU */ - cpumask_set_cpu(cpu, &uncore_cpu_mask); - data = uncore_get_instance(cpu); if (!data) return 0; @@ -138,7 +136,14 @@ static int uncore_event_cpu_online(unsig data->die_id = topology_die_id(cpu); data->domain_id = UNCORE_DOMAIN_ID_INVALID;
- return uncore_freq_add_entry(data, cpu); + ret = uncore_freq_add_entry(data, cpu); + if (ret) + return ret; + + /* Use this CPU on this die as a control CPU */ + cpumask_set_cpu(cpu, &uncore_cpu_mask); + + return 0; }
static int uncore_event_cpu_offline(unsigned int cpu)