[kvm-unit-tests,v2,1/6] x86: Add _safe() and _fep_safe() variants to segment base load instructions

Commit Message

Sean Christopherson Feb. 15, 2025, 1:30 a.m. UTC

From: Maxim Levitsky <[e-mail]>

Add _safe() and _fep_safe() helpers for segment/base instructions; the
helpers will be used to validate various ways of setting the segment bases
and GDT/LDT bases.

Signed-off-by: Maxim Levitsky <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Sean Christopherson <[e-mail]>
---
 lib/x86/desc.h      |  4 ++--
 lib/x86/processor.h | 45 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 47 insertions(+), 2 deletions(-)

Patch

diff --git a/lib/x86/desc.h b/lib/x86/desc.h
index 92c45a48..5349ea57 100644
--- a/lib/x86/desc.h
+++ b/lib/x86/desc.h
@@ -286,8 +286,8 @@  extern unsigned long get_gdt_entry_limit(gdt_entry_t *entry);
 #define asm_safe(insn, inputs...)					\
 	__asm_safe("", insn, inputs)
 
-#define asm_fep_safe(insn, output, inputs...)				\
-	__asm_safe_out1(KVM_FEP, insn, output, inputs)
+#define asm_fep_safe(insn, inputs...)				\
+	__asm_safe_out1(KVM_FEP, insn,, inputs)
 
 #define __asm_safe_out1(fep, insn, output, inputs...)			\
 ({									\
diff --git a/lib/x86/processor.h b/lib/x86/processor.h
index da1ed662..9248a06b 100644
--- a/lib/x86/processor.h
+++ b/lib/x86/processor.h
@@ -468,6 +468,11 @@  static inline int rdmsr_safe(u32 index, uint64_t *val)
 	return rdreg64_safe("rdmsr", index, val);
 }
 
+static inline int rdmsr_fep_safe(u32 index, uint64_t *val)
+{
+	return __rdreg64_safe(KVM_FEP, "rdmsr", index, val);
+}
+
 static inline int wrmsr_safe(u32 index, u64 val)
 {
 	return wrreg64_safe("wrmsr", index, val);
@@ -597,6 +602,16 @@  static inline void lgdt(const struct descriptor_table_ptr *ptr)
 	asm volatile ("lgdt %0" : : "m"(*ptr));
 }
 
+static inline int lgdt_safe(const struct descriptor_table_ptr *ptr)
+{
+	return asm_safe("lgdt %0", "m"(*ptr));
+}
+
+static inline int lgdt_fep_safe(const struct descriptor_table_ptr *ptr)
+{
+	return asm_fep_safe("lgdt %0", "m"(*ptr));
+}
+
 static inline void sgdt(struct descriptor_table_ptr *ptr)
 {
 	asm volatile ("sgdt %0" : "=m"(*ptr));
@@ -607,6 +622,16 @@  static inline void lidt(const struct descriptor_table_ptr *ptr)
 	asm volatile ("lidt %0" : : "m"(*ptr));
 }
 
+static inline int lidt_safe(const struct descriptor_table_ptr *ptr)
+{
+	return asm_safe("lidt %0", "m"(*ptr));
+}
+
+static inline int lidt_fep_safe(const struct descriptor_table_ptr *ptr)
+{
+	return asm_fep_safe("lidt %0", "m"(*ptr));
+}
+
 static inline void sidt(struct descriptor_table_ptr *ptr)
 {
 	asm volatile ("sidt %0" : "=m"(*ptr));
@@ -617,6 +642,16 @@  static inline void lldt(u16 val)
 	asm volatile ("lldt %0" : : "rm"(val));
 }
 
+static inline int lldt_safe(u16 val)
+{
+	return asm_safe("lldt %0", "rm"(val));
+}
+
+static inline int lldt_fep_safe(u16 val)
+{
+	return asm_safe("lldt %0", "rm"(val));
+}
+
 static inline u16 sldt(void)
 {
 	u16 val;
@@ -629,6 +664,16 @@  static inline void ltr(u16 val)
 	asm volatile ("ltr %0" : : "rm"(val));
 }
 
+static inline int ltr_safe(u16 val)
+{
+	return asm_safe("ltr %0", "rm"(val));
+}
+
+static inline int ltr_fep_safe(u16 val)
+{
+	return asm_safe("ltr %0", "rm"(val));
+}
+
 static inline u16 str(void)
 {
 	u16 val;