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/include/asm/compat.h b/arch/x86/include/asm/compat.h
index 7938b84..e7f68b4 100644
--- a/arch/x86/include/asm/compat.h
+++ b/arch/x86/include/asm/compat.h
@@ -6,6 +6,7 @@
*/
#include <linux/types.h>
#include <linux/sched.h>
+#include <asm/processor.h>
#include <asm/user32.h>
#include <asm/unistd.h>
@@ -187,7 +188,20 @@
/*
* The type of struct elf_prstatus.pr_reg in compatible core dumps.
*/
+#ifdef CONFIG_X86_X32_ABI
+typedef struct user_regs_struct compat_elf_gregset_t;
+
+#define PR_REG_SIZE(S) (test_thread_flag(TIF_IA32) ? 68 : 216)
+#define PRSTATUS_SIZE(S) (test_thread_flag(TIF_IA32) ? 144 : 296)
+#define SET_PR_FPVALID(S,V) \
+ do { *(int *) (((void *) &((S)->pr_reg)) + PR_REG_SIZE(0)) = (V); } \
+ while (0)
+
+#define COMPAT_USE_64BIT_TIME \
+ (!!(task_pt_regs(current)->orig_ax & __X32_SYSCALL_BIT))
+#else
typedef struct user_regs_struct32 compat_elf_gregset_t;
+#endif
/*
* A pointer passed in from user mode. This should not
@@ -209,8 +223,16 @@
static inline void __user *arch_compat_alloc_user_space(long len)
{
- struct pt_regs *regs = task_pt_regs(current);
- return (void __user *)regs->sp - len;
+ compat_uptr_t sp;
+
+ if (test_thread_flag(TIF_IA32)) {
+ sp = task_pt_regs(current)->sp;
+ } else {
+ /* -128 for the x32 ABI redzone */
+ sp = percpu_read(old_rsp) - 128;
+ }
+
+ return (void __user *)round_down(sp - len, 16);
}
static inline bool is_compat_task(void)