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 --- Non urgent patch. It can go through regular merge window even if it has fix tag. This is not a current production use case.

Rebased on https://kernel.googlesource.com/pub/scm/linux/kernel/git/pdx86/platform-driv... for-next

.../x86/intel/uncore-frequency/uncore-frequency-tpmi.c | 5 +++++ 1 file changed, 5 insertions(+)

diff --git a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-tpmi.c b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-tpmi.c index 6df55c8e16b7..bfcf92aa4d69 100644 --- a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-tpmi.c +++ b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-tpmi.c @@ -192,9 +192,14 @@ static int uncore_read_control_freq(struct uncore_data *data, unsigned int *valu 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;