Re: [PATCH] perf/x86: Disable uncore on virtualized CPU.

From: Pekka Enberg
Date: Fri Aug 31 2012 - 03:12:19 EST


On Tue, Aug 21, 2012 at 12:08 PM, Yan, Zheng <zheng.z.yan@xxxxxxxxx> wrote:
>> From: "Yan, Zheng" <zheng.z.yan@xxxxxxxxx>
>>
>> Initializing uncore PMU on virtualized CPU may hang the kernel.
>> This is because kvm does not emulate the entire hardware. Thers
>> are lots of uncore related MSRs, making kvm enumerate them all
>> is a non-trival task. So just disable uncore on virtualized CPU.
>>
>> Signed-off-by: Yan, Zheng <zheng.z.yan@xxxxxxxxx>
>> ---
>> arch/x86/kernel/cpu/perf_event_intel_uncore.c | 3 +++
>> 1 file changed, 3 insertions(+)
>>
>> diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.c b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
>> index 0a55710..2f005ba 100644
>> --- a/arch/x86/kernel/cpu/perf_event_intel_uncore.c
>> +++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
>> @@ -2898,6 +2898,9 @@ static int __init intel_uncore_init(void)
>> if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL)
>> return -ENODEV;
>>
>> + if (cpu_has_hypervisor)
>> + return -ENODEV;
>> +
>> ret = uncore_pci_init();
>> if (ret)
>> goto fail;

On Tue, Aug 21, 2012 at 3:55 PM, Pekka Enberg <penberg@xxxxxxxxxx> wrote:
> Tested-by: Pekka Enberg <penberg@xxxxxxxxxx>

Ping? I have not seen a tip bot email for this. Is the patch queued?
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