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Patch "x86/msr: Add definitions for new speculation control MSRs" has been added to the 4.15-stable tree

PATCH [email protected] 1 participant 1 message Feb 4, 2018

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This is a note to let you know that I've just added the patch titled

x86/msr: Add definitions for new speculation control MSRs

to the 4.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
x86msr_Add_definitions_for_new_speculation_control_MSRs.patch
and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

Subject: x86/msr: Add definitions for new speculation control MSRs
From: David Woodhouse [email protected]
Date: Thu Jan 25 16:14:12 2018 +0000

From: David Woodhouse [email protected]

commit 1e340c60d0dd3ae07b5bedc16a0469c14b9f3410

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

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

---
 arch/x86/include/asm/msr-index.h |   12 ++++++++++++
 1 file changed, 12 insertions(+)
arch/x86/include/asm/msr-index.h +12 -0
@@ -39,6 +39,13 @@
 
 /* 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_PPIN_CTL			0x0000004e
 #define MSR_PPIN			0x0000004f
 
@@ -57,6 +64,11 @@
 #define SNB_C3_AUTO_UNDEMOTE		(1UL << 28)
 
 #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
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.15/x86pti_Do_not_enable_PTI_on_CPUs_which_are_not_vulnerable_to_Meltdown.patch queue-4.15/x86cpufeature_Blacklist_SPEC_CTRLPRED_CMD_on_early_Spectre_v2_microcodes.patch queue-4.15/x86cpufeatures_Add_Intel_feature_bits_for_Speculation_Control.patch queue-4.15/KVM_VMX_Make_indirect_call_speculation_safe.patch queue-4.15/x86msr_Add_definitions_for_new_speculation_control_MSRs.patch queue-4.15/x86cpufeatures_Add_CPUID_7_EDX_CPUID_leaf.patch queue-4.15/x86cpufeatures_Add_AMD_feature_bits_for_Speculation_Control.patch queue-4.15/x86speculation_Add_basic_IBPB_(Indirect_Branch_Prediction_Barrier)_support.patch queue-4.15/x86speculation_Simplify_indirect_branch_prediction_barrier().patch queue-4.15/KVM_x86_Make_indirect_calls_in_emulator_speculation_safe.patch queue-4.15/x86retpoline_Simplify_vmexit_fill_RSB().patch queue-4.15/x86cpufeatures_Clean_up_Spectre_v2_related_CPUID_flags.patch