x86/cpufeature: Add feature bit for Intel's Silicon Debug CPUID bit
x86/cpufeature: Add feature bit for Intel's Silicon Debug CPUID bit

Add a CPUID feature bit for the SDBG (Silicon Debug) CPU feature
found on recent Intel systems starting with Haswell.

Using the IA32_DEBUG_INTERFACE MSR (index C80H) one can at least
detect if SDBG has been enabled by the firmware and if it has
been used or not.

Signed-off-by: Mathias Krause <64568d9183dcfcdd0a6fb47964820a1cdaf94ecc@googlemail.com>
Signed-off-by: Borislav Petkov <0691a664b24b6f15b20cd5aee64b72271db08be1@suse.de>
Cc: Aaron Lu <e835aaae27ef45c770cbc83733586d01aadc3a43@intel.com>
Cc: Dave Hansen <71bcd3d88361b22cd828f9a350d19d8775f56d4e@linux.intel.com>
Cc: Dirk Brandewie <90b1bc8a6ba9849b6d077cb338e79c4550ccbc5f@intel.com>
Cc: H. Peter Anvin <8a453bad9912ffe59bc0f0b8abe03df9be19379e@zytor.com>
Cc: Josh Triplett <c028c213ed5efcf30c3f4fc7361dbde0c893c5b7@joshtriplett.org>
Cc: Linus Torvalds <69652caca27c8b940640ad396ab71f93cacec34f@linux-foundation.org>
Cc: Peter Zijlstra <3fddac958924aef220f202ca567388ddab3f14a8@infradead.org>
Cc: Ross Zwisler <19f56ffe3ac18f81d12a74c011e044bc6df12299@linux.intel.com>
Cc: Thomas Gleixner <00e4cf8f46a57000a44449bf9dd8cbbcc209fd2a@linutronix.de>
Link: http://lkml.kernel.org/r/1437330403-12102-1-git-send-email-64568d9183dcfcdd0a6fb47964820a1cdaf94ecc@googlemail.com
Signed-off-by: Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@kernel.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs