[kvm-unit-tests PATCH 1/5] x86: add _safe and _fep_safe variants to segment base load instructions

Maxim Levitsky
2024-09-07T00:54:46Z

_safe and _fep_safe functions will be used to validate various ways of
setting the segment bases and GDT/LDT bases.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
---
lib/x86/desc.h | 4 ++--
lib/x86/processor.h | 45 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/lib/x86/desc.h b/lib/x86/desc.h
index 92c45a48f..5349ea572 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 da1ed6628..9248a06b2 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;
--
2.26.3