6.16-stable review patch. If anyone has any objections, please let me know.
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From: Srinivas Pandruvada srinivas.pandruvada@linux.intel.com
commit dff6f36878799a5ffabd15336ce993dc737374dc upstream.
Add the missing write_blocked check for updating sysfs related to uncore efficiency latency control (ELC). If write operation is blocked return error.
Fixes: bb516dc79c4a ("platform/x86/intel-uncore-freq: Add support for efficiency latency control") Signed-off-by: Srinivas Pandruvada srinivas.pandruvada@linux.intel.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250727210513.2898630-1-srinivas.pandruvada@linux... 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-tpmi.c | 5 +++++ 1 file changed, 5 insertions(+)
--- a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-tpmi.c +++ b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-tpmi.c @@ -191,9 +191,14 @@ static int uncore_read_control_freq(stru static int write_eff_lat_ctrl(struct uncore_data *data, unsigned int val, enum uncore_index index) { struct tpmi_uncore_cluster_info *cluster_info; + struct tpmi_uncore_struct *uncore_root; u64 control;
cluster_info = container_of(data, struct tpmi_uncore_cluster_info, uncore_data); + uncore_root = cluster_info->uncore_root; + + if (uncore_root->write_blocked) + return -EPERM;
if (cluster_info->root_domain) return -ENODATA;