x86/bugs: Rename MDS machinery to something more generic

It will be used by other x86 mitigations.

No functional changes.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>

6 files changed, 30 insertions, 29 deletions

diff --git a/arch/x86/entry/entry.S b/arch/x86/entry/entry.S
index 175958b02f2b..8e9a0cc20a4a 100644
--- a/arch/x86/entry/entry.S
+++ b/arch/x86/entry/entry.S
@@ -36,20 +36,20 @@ EXPORT_SYMBOL_GPL(write_ibpb);
 
 /*
  * Define the VERW operand that is disguised as entry code so that
- * it can be referenced with KPTI enabled. This ensure VERW can be
+ * it can be referenced with KPTI enabled. This ensures VERW can be
  * used late in exit-to-user path after page tables are switched.
  */
 .pushsection .entry.text, "ax"
 
 .align L1_CACHE_BYTES, 0xcc
-SYM_CODE_START_NOALIGN(mds_verw_sel)
+SYM_CODE_START_NOALIGN(x86_verw_sel)
 	UNWIND_HINT_UNDEFINED
 	ANNOTATE_NOENDBR
 	.word __KERNEL_DS
 .align L1_CACHE_BYTES, 0xcc
-SYM_CODE_END(mds_verw_sel);
+SYM_CODE_END(x86_verw_sel);
 /* For KVM */
-EXPORT_SYMBOL_GPL(mds_verw_sel);
+EXPORT_SYMBOL_GPL(x86_verw_sel);
 
 .popsection
 
diff --git a/arch/x86/include/asm/irqflags.h b/arch/x86/include/asm/irqflags.h
index 9a9b21b78905..b30e5474c18e 100644
--- a/arch/x86/include/asm/irqflags.h
+++ b/arch/x86/include/asm/irqflags.h
@@ -44,13 +44,13 @@ static __always_inline void native_irq_enable(void)
 
 static __always_inline void native_safe_halt(void)
 {
-	mds_idle_clear_cpu_buffers();
+	x86_idle_clear_cpu_buffers();
 	asm volatile("sti; hlt": : :"memory");
 }
 
 static __always_inline void native_halt(void)
 {
-	mds_idle_clear_cpu_buffers();
+	x86_idle_clear_cpu_buffers();
 	asm volatile("hlt": : :"memory");
 }
 
diff --git a/arch/x86/include/asm/mwait.h b/arch/x86/include/asm/mwait.h
index dd2b129b0418..cc34c3fd197b 100644
--- a/arch/x86/include/asm/mwait.h
+++ b/arch/x86/include/asm/mwait.h
@@ -43,7 +43,7 @@ static __always_inline void __monitorx(const void *eax, u32 ecx, u32 edx)
 
 static __always_inline void __mwait(u32 eax, u32 ecx)
 {
-	mds_idle_clear_cpu_buffers();
+	x86_idle_clear_cpu_buffers();
 
 	/*
 	 * Use the instruction mnemonic with implicit operands, as the LLVM
@@ -98,7 +98,7 @@ static __always_inline void __mwaitx(u32 eax, u32 ebx, u32 ecx)
  */
 static __always_inline void __sti_mwait(u32 eax, u32 ecx)
 {
-	mds_idle_clear_cpu_buffers();
+	x86_idle_clear_cpu_buffers();
 
 	asm volatile("sti; mwait" :: "a" (eax), "c" (ecx));
 }
diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
index 20d754b98f3f..5dcd75bb5e0d 100644
--- a/arch/x86/include/asm/nospec-branch.h
+++ b/arch/x86/include/asm/nospec-branch.h
@@ -302,22 +302,22 @@
 .endm
 
 /*
- * Macro to execute VERW instruction that mitigate transient data sampling
- * attacks such as MDS. On affected systems a microcode update overloaded VERW
- * instruction to also clear the CPU buffers. VERW clobbers CFLAGS.ZF.
- *
+ * Macro to execute VERW insns that mitigate transient data sampling
+ * attacks such as MDS or TSA. On affected systems a microcode update
+ * overloaded VERW insns to also clear the CPU buffers. VERW clobbers
+ * CFLAGS.ZF.
  * Note: Only the memory operand variant of VERW clears the CPU buffers.
  */
 .macro CLEAR_CPU_BUFFERS
 #ifdef CONFIG_X86_64
-	ALTERNATIVE "", "verw mds_verw_sel(%rip)", X86_FEATURE_CLEAR_CPU_BUF
+	ALTERNATIVE "", "verw x86_verw_sel(%rip)", X86_FEATURE_CLEAR_CPU_BUF
 #else
 	/*
 	 * In 32bit mode, the memory operand must be a %cs reference. The data
 	 * segments may not be usable (vm86 mode), and the stack segment may not
 	 * be flat (ESPFIX32).
 	 */
-	ALTERNATIVE "", "verw %cs:mds_verw_sel", X86_FEATURE_CLEAR_CPU_BUF
+	ALTERNATIVE "", "verw %cs:x86_verw_sel", X86_FEATURE_CLEAR_CPU_BUF
 #endif
 .endm
 
@@ -567,24 +567,24 @@ DECLARE_STATIC_KEY_FALSE(switch_mm_always_ibpb);
 
 DECLARE_STATIC_KEY_FALSE(switch_vcpu_ibpb);
 
-DECLARE_STATIC_KEY_FALSE(mds_idle_clear);
+DECLARE_STATIC_KEY_FALSE(cpu_buf_idle_clear);
 
 DECLARE_STATIC_KEY_FALSE(switch_mm_cond_l1d_flush);
 
 DECLARE_STATIC_KEY_FALSE(cpu_buf_vm_clear);
 
-extern u16 mds_verw_sel;
+extern u16 x86_verw_sel;
 
 #include <asm/segment.h>
 
 /**
- * mds_clear_cpu_buffers - Mitigation for MDS and TAA vulnerability
+ * x86_clear_cpu_buffers - Buffer clearing support for different x86 CPU vulns
  *
  * This uses the otherwise unused and obsolete VERW instruction in
  * combination with microcode which triggers a CPU buffer flush when the
  * instruction is executed.
  */
-static __always_inline void mds_clear_cpu_buffers(void)
+static __always_inline void x86_clear_cpu_buffers(void)
 {
 	static const u16 ds = __KERNEL_DS;
 
@@ -601,14 +601,15 @@ static __always_inline void mds_clear_cpu_buffers(void)
 }
 
 /**
- * mds_idle_clear_cpu_buffers - Mitigation for MDS vulnerability
+ * x86_idle_clear_cpu_buffers - Buffer clearing support in idle for the MDS
+ * vulnerability
  *
  * Clear CPU buffers if the corresponding static key is enabled
  */
-static __always_inline void mds_idle_clear_cpu_buffers(void)
+static __always_inline void x86_idle_clear_cpu_buffers(void)
 {
-	if (static_branch_likely(&mds_idle_clear))
-		mds_clear_cpu_buffers();
+	if (static_branch_likely(&cpu_buf_idle_clear))
+		x86_clear_cpu_buffers();
 }
 
 #endif /* __ASSEMBLER__ */
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 7f94e6a5497d..258ed3d2b6a9 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -169,9 +169,9 @@ DEFINE_STATIC_KEY_FALSE(switch_mm_always_ibpb);
 DEFINE_STATIC_KEY_FALSE(switch_vcpu_ibpb);
 EXPORT_SYMBOL_GPL(switch_vcpu_ibpb);
 
-/* Control MDS CPU buffer clear before idling (halt, mwait) */
-DEFINE_STATIC_KEY_FALSE(mds_idle_clear);
-EXPORT_SYMBOL_GPL(mds_idle_clear);
+/* Control CPU buffer clear before idling (halt, mwait) */
+DEFINE_STATIC_KEY_FALSE(cpu_buf_idle_clear);
+EXPORT_SYMBOL_GPL(cpu_buf_idle_clear);
 
 /*
  * Controls whether l1d flush based mitigations are enabled,
@@ -637,7 +637,7 @@ static void __init mmio_apply_mitigation(void)
 	 * is required irrespective of SMT state.
 	 */
 	if (!(x86_arch_cap_msr & ARCH_CAP_FBSDP_NO))
-		static_branch_enable(&mds_idle_clear);
+		static_branch_enable(&cpu_buf_idle_clear);
 
 	if (mmio_nosmt || cpu_mitigations_auto_nosmt())
 		cpu_smt_disable(false);
@@ -2249,10 +2249,10 @@ static void update_mds_branch_idle(void)
 		return;
 
 	if (sched_smt_active()) {
-		static_branch_enable(&mds_idle_clear);
+		static_branch_enable(&cpu_buf_idle_clear);
 	} else if (mmio_mitigation == MMIO_MITIGATION_OFF ||
 		   (x86_arch_cap_msr & ARCH_CAP_FBSDP_NO)) {
-		static_branch_disable(&mds_idle_clear);
+		static_branch_disable(&cpu_buf_idle_clear);
 	}
 }
 
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 4953846cb30d..191a9ed0da22 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7291,7 +7291,7 @@ static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu,
 		vmx_l1d_flush(vcpu);
 	else if (static_branch_unlikely(&cpu_buf_vm_clear) &&
 		 kvm_arch_has_assigned_device(vcpu->kvm))
-		mds_clear_cpu_buffers();
+		x86_clear_cpu_buffers();
 
 	vmx_disable_fb_clear(vmx);