perf/x86/intel: Protect LBR and extra_regs against KVM lying

With -cpu host, KVM reports LBR and extra_regs support, if the host has
support.

When the guest perf driver tries to access LBR or extra_regs MSR,
it #GPs all MSR accesses,since KVM doesn't handle LBR and extra_regs support.
So check the related MSRs access right once at initialization time to avoid
the error access at runtime.

For reproducing the issue, please build the kernel with CONFIG_KVM_INTEL = y
(for host kernel).
And CONFIG_PARAVIRT = n and CONFIG_KVM_GUEST = n (for guest kernel).
Start the guest with -cpu host.
Run perf record with --branch-any or --branch-filter in guest to trigger LBR
Run perf stat offcore events (E.g. LLC-loads/LLC-load-misses ...) in guest to
trigger offcore_rsp #GP

Signed-off-by: Kan Liang <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Maria Dimakopoulou <[email protected]>
Cc: Mark Davies <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Yan, Zheng <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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