[PATCH 3.16 043/410] x86/msr: Add definitions for new speculation control MSRs

From: Ben Hutchings
Date: Thu Jun 07 2018 - 10:29:43 EST


3.16.57-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: David Woodhouse <dwmw@xxxxxxxxxxxx>

commit 1e340c60d0dd3ae07b5bedc16a0469c14b9f3410 upstream.

Add MSR and bit definitions for SPEC_CTRL, PRED_CMD and ARCH_CAPABILITIES.

See Intel's 336996-Speculative-Execution-Side-Channel-Mitigations.pdf

Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: gnomes@xxxxxxxxxxxxxxxxxxx
Cc: ak@xxxxxxxxxxxxxxx
Cc: ashok.raj@xxxxxxxxx
Cc: dave.hansen@xxxxxxxxx
Cc: karahmed@xxxxxxxxx
Cc: arjan@xxxxxxxxxxxxxxx
Cc: torvalds@xxxxxxxxxxxxxxxxxxxx
Cc: peterz@xxxxxxxxxxxxx
Cc: bp@xxxxxxxxx
Cc: pbonzini@xxxxxxxxxx
Cc: tim.c.chen@xxxxxxxxxxxxxxx
Cc: gregkh@xxxxxxxxxxxxxxxxxxxx
Link: https://lkml.kernel.org/r/1516896855-7642-5-git-send-email-dwmw@xxxxxxxxxxxx
Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
arch/x86/include/uapi/asm/msr-index.h | 12 ++++++++++++
1 file changed, 12 insertions(+)

--- a/arch/x86/include/uapi/asm/msr-index.h
+++ b/arch/x86/include/uapi/asm/msr-index.h
@@ -32,6 +32,13 @@
#define EFER_FFXSR (1<<_EFER_FFXSR)

/* Intel MSRs. Some also available on other CPUs */
+#define MSR_IA32_SPEC_CTRL 0x00000048 /* Speculation Control */
+#define SPEC_CTRL_IBRS (1 << 0) /* Indirect Branch Restricted Speculation */
+#define SPEC_CTRL_STIBP (1 << 1) /* Single Thread Indirect Branch Predictors */
+
+#define MSR_IA32_PRED_CMD 0x00000049 /* Prediction Command */
+#define PRED_CMD_IBPB (1 << 0) /* Indirect Branch Prediction Barrier */
+
#define MSR_IA32_PERFCTR0 0x000000c1
#define MSR_IA32_PERFCTR1 0x000000c2
#define MSR_FSB_FREQ 0x000000cd
@@ -46,6 +53,11 @@

#define MSR_PLATFORM_INFO 0x000000ce
#define MSR_MTRRcap 0x000000fe
+
+#define MSR_IA32_ARCH_CAPABILITIES 0x0000010a
+#define ARCH_CAP_RDCL_NO (1 << 0) /* Not susceptible to Meltdown */
+#define ARCH_CAP_IBRS_ALL (1 << 1) /* Enhanced IBRS support */
+
#define MSR_IA32_BBL_CR_CTL 0x00000119
#define MSR_IA32_BBL_CR_CTL3 0x0000011e