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

[Yan, Zheng]

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;
-- 
1.7.11.2

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