linux-kernel - [PATCH 4.14 050/293] x86/cpufeatures: Add FDP_EXCPTN_ONLY and ZERO_FCS

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Date:   Mon, 29 Jul 2019 21:19:01 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Aaron Lewis <aaronlewis@...gle.com>,
        Borislav Petkov <bp@...e.de>,
        Jim Mattson <jmattson@...gle.com>,
        Fenghua Yu <fenghua.yu@...el.com>,
        Frederic Weisbecker <frederic@...nel.org>,
        "H. Peter Anvin" <hpa@...or.com>, Ingo Molnar <mingo@...hat.com>,
        Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>,
        marcorr@...gle.com, Peter Feiner <pfeiner@...gle.com>,
        pshier@...gle.com, Robert Hoo <robert.hu@...ux.intel.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Thomas Lendacky <Thomas.Lendacky@....com>,
        x86-ml <x86@...nel.org>, Sasha Levin <sashal@...nel.org>
Subject: [PATCH 4.14 050/293] x86/cpufeatures: Add FDP_EXCPTN_ONLY and ZERO_FCS_FDS

[ Upstream commit cbb99c0f588737ec98c333558922ce47e9a95827 ]

Add the CPUID enumeration for Intel's de-feature bits to accommodate
passing these de-features through to kvm guests.

These de-features are (from SDM vol 1, section 8.1.8):
 - X86_FEATURE_FDP_EXCPTN_ONLY: If CPUID.(EAX=07H,ECX=0H):EBX[bit 6] = 1, the
   data pointer (FDP) is updated only for the x87 non-control instructions that
   incur unmasked x87 exceptions.
 - X86_FEATURE_ZERO_FCS_FDS: If CPUID.(EAX=07H,ECX=0H):EBX[bit 13] = 1, the
   processor deprecates FCS and FDS; it saves each as 0000H.

Signed-off-by: Aaron Lewis <aaronlewis@...gle.com>
Signed-off-by: Borislav Petkov <bp@...e.de>
Reviewed-by: Jim Mattson <jmattson@...gle.com>
Cc: Fenghua Yu <fenghua.yu@...el.com>
Cc: Frederic Weisbecker <frederic@...nel.org>
Cc: "H. Peter Anvin" <hpa@...or.com>
Cc: Ingo Molnar <mingo@...hat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
Cc: marcorr@...gle.com
Cc: Peter Feiner <pfeiner@...gle.com>
Cc: pshier@...gle.com
Cc: Robert Hoo <robert.hu@...ux.intel.com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Cc: Thomas Lendacky <Thomas.Lendacky@....com>
Cc: x86-ml <x86@...nel.org>
Link: https://lkml.kernel.org/r/20190605220252.103406-1-aaronlewis@google.com
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 arch/x86/include/asm/cpufeatures.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 48ef9ed8226d..4cb8315c521f 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -239,12 +239,14 @@
 #define X86_FEATURE_BMI1		( 9*32+ 3) /* 1st group bit manipulation extensions */
 #define X86_FEATURE_HLE			( 9*32+ 4) /* Hardware Lock Elision */
 #define X86_FEATURE_AVX2		( 9*32+ 5) /* AVX2 instructions */
+#define X86_FEATURE_FDP_EXCPTN_ONLY	( 9*32+ 6) /* "" FPU data pointer updated only on x87 exceptions */
 #define X86_FEATURE_SMEP		( 9*32+ 7) /* Supervisor Mode Execution Protection */
 #define X86_FEATURE_BMI2		( 9*32+ 8) /* 2nd group bit manipulation extensions */
 #define X86_FEATURE_ERMS		( 9*32+ 9) /* Enhanced REP MOVSB/STOSB instructions */
 #define X86_FEATURE_INVPCID		( 9*32+10) /* Invalidate Processor Context ID */
 #define X86_FEATURE_RTM			( 9*32+11) /* Restricted Transactional Memory */
 #define X86_FEATURE_CQM			( 9*32+12) /* Cache QoS Monitoring */
+#define X86_FEATURE_ZERO_FCS_FDS	( 9*32+13) /* "" Zero out FPU CS and FPU DS */
 #define X86_FEATURE_MPX			( 9*32+14) /* Memory Protection Extension */
 #define X86_FEATURE_RDT_A		( 9*32+15) /* Resource Director Technology Allocation */
 #define X86_FEATURE_AVX512F		( 9*32+16) /* AVX-512 Foundation */
-- 
2.20.1