From: Thomas Gleixner Date: Fri, 3 Aug 2018 11:06:35 +0000 (+0200) Subject: x86/intel_rdt: Disable PMU access X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=4a7a54a55e7237386cacc73f173e74329773ac93;p=linux.git x86/intel_rdt: Disable PMU access Peter is objecting to the direct PMU access in RDT. Right now the PMU usage is broken anyway as it is not coordinated with perf. Until this discussion settled, disable the PMU mechanics by simply rejecting the type '2' measurement in the resctrl file. Reported-by: Peter Zijlstra Signed-off-by: Thomas Gleixner Cc: Reinette Chatre Cc: Dave Hansen Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com CC: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: hpa@zytor.com --- diff --git a/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c b/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c index f80c58f8adc31..40f3903ae5d98 100644 --- a/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c +++ b/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c @@ -1171,7 +1171,7 @@ static ssize_t pseudo_lock_measure_trigger(struct file *file, buf[buf_size] = '\0'; ret = kstrtoint(buf, 10, &sel); if (ret == 0) { - if (sel != 1 && sel != 2) + if (sel != 1) return -EINVAL; ret = debugfs_file_get(file->f_path.dentry); if (ret)