x32: Handle process creation
Allow an x32 process to be started.
Originally-by: H. J. Lu <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 5fe2fba..a0701da 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -364,7 +364,9 @@
void start_thread_ia32(struct pt_regs *regs, u32 new_ip, u32 new_sp)
{
start_thread_common(regs, new_ip, new_sp,
- __USER32_CS, __USER32_DS, __USER32_DS);
+ test_thread_flag(TIF_X32)
+ ? __USER_CS : __USER32_CS,
+ __USER_DS, __USER_DS);
}
#endif
@@ -508,6 +510,7 @@
/* Make sure to be in 64bit mode */
clear_thread_flag(TIF_IA32);
+ clear_thread_flag(TIF_X32);
clear_thread_flag(TIF_ADDR32);
clear_thread_flag(TIF_X32);
@@ -522,22 +525,28 @@
current->personality &= ~READ_IMPLIES_EXEC;
}
-void set_personality_ia32(void)
+void set_personality_ia32(bool x32)
{
/* inherit personality from parent */
/* Make sure to be in 32bit mode */
- set_thread_flag(TIF_IA32);
set_thread_flag(TIF_ADDR32);
- clear_thread_flag(TIF_X32);
- current->personality |= force_personality32;
/* Mark the associated mm as containing 32-bit tasks. */
if (current->mm)
current->mm->context.ia32_compat = 1;
- /* Prepare the first "return" to user space */
- current_thread_info()->status |= TS_COMPAT;
+ if (x32) {
+ clear_thread_flag(TIF_IA32);
+ set_thread_flag(TIF_X32);
+ current->personality &= ~READ_IMPLIES_EXEC;
+ } else {
+ set_thread_flag(TIF_IA32);
+ clear_thread_flag(TIF_X32);
+ current->personality |= force_personality32;
+ /* Prepare the first "return" to user space */
+ current_thread_info()->status |= TS_COMPAT;
+ }
}
unsigned long get_wchan(struct task_struct *p)