From c2c1d493fa0ee16491bffd6682cf4f479b8792c2 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 15 Aug 2007 12:38:58 +0200 Subject: i386: Handle P6s without performance counters in nmi watchdog I got an oops while booting a 32bit kernel on KVM because it doesn't implement performance counters used by the NMI watchdog. Handle this case. Cc: Avi Kivity Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- arch/i386/kernel/cpu/perfctr-watchdog.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/i386/kernel/cpu/perfctr-watchdog.c b/arch/i386/kernel/cpu/perfctr-watchdog.c index 4d26d514c56..996f6f89ce8 100644 --- a/arch/i386/kernel/cpu/perfctr-watchdog.c +++ b/arch/i386/kernel/cpu/perfctr-watchdog.c @@ -346,7 +346,9 @@ static int setup_p6_watchdog(unsigned nmi_hz) perfctr_msr = MSR_P6_PERFCTR0; evntsel_msr = MSR_P6_EVNTSEL0; - wrmsrl(perfctr_msr, 0UL); + /* KVM doesn't implement this MSR */ + if (wrmsr_safe(perfctr_msr, 0, 0) < 0) + return 0; evntsel = P6_EVNTSEL_INT | P6_EVNTSEL_OS -- cgit v1.2.3-18-g5258