Signed-off-by: SU Hang <darcy.sh@xxxxxxxxxxxx>
---
lib/x86/usermode.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/lib/x86/usermode.c b/lib/x86/usermode.c
index 477cb9f..e4cb899 100644
--- a/lib/x86/usermode.c
+++ b/lib/x86/usermode.c
@@ -12,7 +12,6 @@
#include <stdint.h>
#define USERMODE_STACK_SIZE 0x2000
-#define RET_TO_KERNEL_IRQ 0x20
static jmp_buf jmpbuf;
@@ -40,9 +39,11 @@ uint64_t run_in_user(usermode_func func, unsigned int fault_vector,
static unsigned char user_stack[USERMODE_STACK_SIZE];
*raised_vector = 0;
- set_idt_entry(RET_TO_KERNEL_IRQ, &ret_to_kernel, 3);
handle_exception(fault_vector,
restore_exec_to_jmpbuf_exception_handler);
+ wrmsr(MSR_EFER, rdmsr(MSR_EFER) | EFER_SCE);
+ wrmsr(MSR_STAR, ((u64)(USER_CS32 << 16) | KERNEL_CS) << 32);
+ wrmsr(MSR_LSTAR, (u64)&ret_to_kernel);
if (setjmp(jmpbuf) != 0) {
*raised_vector = 1;
@@ -73,7 +74,7 @@ uint64_t run_in_user(usermode_func func, unsigned int fault_vector,
"mov %[arg4], %%rcx\n\t"
"call *%[func]\n\t"
/* Return to kernel via system call */
- "int %[kernel_entry_vector]\n\t"
+ "syscall\n\t"
/* Kernel Mode */
"ret_to_kernel:\n\t"
"mov %[rsp0], %%rsp\n\t"
@@ -89,8 +90,7 @@ uint64_t run_in_user(usermode_func func, unsigned int fault_vector,
[user_ds]"i"(USER_DS),
[user_cs]"i"(USER_CS),
[user_stack_top]"r"(user_stack +
- sizeof(user_stack)),
- [kernel_entry_vector]"i"(RET_TO_KERNEL_IRQ)
+ sizeof(user_stack))
:
"rsi", "rdi", "rbx", "rcx", "rdx", "r8", "r9", "r10", "r11");
--
2.32.0.3.g01195cf9f
