From a026dfecc035f213c1cfa0bf6407ce3155f6a9df Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 13 May 2009 10:02:57 +0200 Subject: [PATCH] perf_counter: x86: Allow unpriviliged use of NMIs Apply sysctl_perf_counter_priv to NMIs. Also, fail the counter creation instead of silently down-grading to regular interrupts. [ Impact: allow wider perf-counter usage ] Signed-off-by: Peter Zijlstra Cc: Paul Mackerras Cc: Corey Ashford LKML-Reference: Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/perf_counter.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c index 88ae8cebf3c1..c19e927b6979 100644 --- a/arch/x86/kernel/cpu/perf_counter.c +++ b/arch/x86/kernel/cpu/perf_counter.c @@ -280,8 +280,11 @@ static int __hw_perf_counter_init(struct perf_counter *counter) * If privileged enough, allow NMI events: */ hwc->nmi = 0; - if (capable(CAP_SYS_ADMIN) && hw_event->nmi) + if (hw_event->nmi) { + if (sysctl_perf_counter_priv && !capable(CAP_SYS_ADMIN)) + return -EACCES; hwc->nmi = 1; + } hwc->irq_period = hw_event->irq_period; if ((s64)hwc->irq_period <= 0 || hwc->irq_period > x86_pmu.max_period) -- 2.20.1