From 8d330919927ea31fa083b5a80084dc991da813a0 Mon Sep 17 00:00:00 2001 From: Lin Ming <ming.m.lin@intel.com> Date: Wed, 25 Aug 2010 21:06:32 +0000 Subject: [PATCH] perf, x86, Pentium4: Clear the P4_CCCR_FORCE_OVF flag If on Pentium4 CPUs the FORCE_OVF flag is set then an NMI happens on every event, which can generate a flood of NMIs. Clear it. Reported-by: Vince Weaver <vweaver1@eecs.utk.edu> Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> --- arch/x86/kernel/cpu/perf_event_p4.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/kernel/cpu/perf_event_p4.c b/arch/x86/kernel/cpu/perf_event_p4.c index febb12cea79526..7e578e9cc58bd5 100644 --- a/arch/x86/kernel/cpu/perf_event_p4.c +++ b/arch/x86/kernel/cpu/perf_event_p4.c @@ -497,6 +497,8 @@ static int p4_hw_config(struct perf_event *event) event->hw.config |= event->attr.config & (p4_config_pack_escr(P4_ESCR_MASK_HT) | p4_config_pack_cccr(P4_CCCR_MASK_HT | P4_CCCR_RESERVED)); + + event->hw.config &= ~P4_CCCR_FORCE_OVF; } rc = x86_setup_perfctr(event); -- GitLab