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x86/cpufeature: Move processor tracing out of scattered features
authorPaolo Bonzini <pbonzini@redhat.com>
Tue, 16 Jan 2018 15:42:25 +0000 (16:42 +0100)
committerIngo Molnar <mingo@kernel.org>
Wed, 17 Jan 2018 06:38:39 +0000 (07:38 +0100)
commit4fdec2034b7540dda461c6ba33325dfcff345c64
treece73af3cc5416465dfba476e3cd46c7713c91bf6
parent385d11b152c4eb638eeb769edcb3249533bb9a00
x86/cpufeature: Move processor tracing out of scattered features

Processor tracing is already enumerated in word 9 (CPUID[7,0].EBX),
so do not duplicate it in the scattered features word.

Besides being more tidy, this will be useful for KVM when it presents
processor tracing to the guests.  KVM selects host features that are
supported by both the host kernel (depending on command line options,
CPU errata, or whatever) and KVM.  Whenever a full feature word exists,
KVM's code is written in the expectation that the CPUID bit number
matches the X86_FEATURE_* bit number, but this is not the case for
X86_FEATURE_INTEL_PT.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luwei Kang <luwei.kang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Link: http://lkml.kernel.org/r/1516117345-34561-1-git-send-email-pbonzini@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/include/asm/cpufeatures.h
arch/x86/kernel/cpu/scattered.c