[PATCH 4.20 170/171] x86: Add TSX Force Abort CPUID/MSR

Greg Kroah-Hartman
2019-03-12T17:58:59Z

From: "Peter Zijlstra (Intel)" <peterz@infradead.org>

commit 52f64909409c17adf54fcf5f9751e0544ca3a6b4 upstream

Skylake systems will receive a microcode update to address a TSX
errata. This microcode will (by default) clobber PMC3 when TSX
instructions are (speculatively or not) executed.

It also provides an MSR to cause all TSX transaction to abort and
preserve PMC3.

Add the CPUID enumeration and MSR definition.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/include/asm/cpufeatures.h | 1 +
arch/x86/include/asm/msr-index.h | 6 ++++++
2 files changed, 7 insertions(+)

--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -342,6 +342,7 @@
/* Intel-defined CPU features, CPUID level 0x00000007:0 (EDX), word 18 */
#define X86_FEATURE_AVX512_4VNNIW (18*32+ 2) /* AVX-512 Neural Network Instructions */
#define X86_FEATURE_AVX512_4FMAPS (18*32+ 3) /* AVX-512 Multiply Accumulation Single precision */
+#define X86_FEATURE_TSX_FORCE_ABORT (18*32+13) /* "" TSX_FORCE_ABORT */
#define X86_FEATURE_PCONFIG (18*32+18) /* Intel PCONFIG */
#define X86_FEATURE_SPEC_CTRL (18*32+26) /* "" Speculation Control (IBRS + IBPB) */
#define X86_FEATURE_INTEL_STIBP (18*32+27) /* "" Single Thread Indirect Branch Predictors */
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -630,6 +630,12 @@

#define MSR_IA32_TSC_DEADLINE 0x000006E0

+
+#define MSR_TSX_FORCE_ABORT 0x0000010F
+
+#define MSR_TFA_RTM_FORCE_ABORT_BIT 0
+#define MSR_TFA_RTM_FORCE_ABORT BIT_ULL(MSR_TFA_RTM_FORCE_ABORT_BIT)
+
/* P4/Xeon+ specific */
#define MSR_IA32_MCG_EAX 0x00000180
#define MSR_IA32_MCG_EBX 0x00000181