Logically, we just want to jump around the "call *sys_call_table(,%rax,8)"
if syscall number is too big, we do not specifically target
"int_ret_from_sys_call" label.

Use a local numeric label for this jump.

This also makes code smaller because jumps to global labels
are never translated to short jump insns by as.

Signed-off-by: Denys Vlasenko <[email protected]>
CC: Linus Torvalds <[email protected]>
CC: Steven Rostedt <[email protected]>
CC: Ingo Molnar <[email protected]>
CC: Borislav Petkov <[email protected]>
CC: "H. Peter Anvin" <[email protected]>
CC: Andy Lutomirski <[email protected]>
CC: Oleg Nesterov <[email protected]>
CC: Frederic Weisbecker <[email protected]>
CC: Alexei Starovoitov <[email protected]>
CC: Will Drewry <[email protected]>
CC: Kees Cook <[email protected]>
CC: [email protected]
CC: [email protected]
---
 arch/x86/kernel/entry_64.S | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index f49f973..e498542 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -331,10 +331,11 @@ tracesys_phase2:
        andl $__SYSCALL_MASK,%eax
        cmpl $__NR_syscall_max,%eax
 #endif
-       ja   int_ret_from_sys_call      /* RAX(%rsp) is already set */
+       ja      1f      /* return -ENOSYS (already in pt_regs->ax) */
        movq %r10,%rcx  /* fixup for C */
        call *sys_call_table(,%rax,8)
        movq %rax,RAX(%rsp)
+1:
        /* Use IRET because user could have changed pt_regs->foo */
 
 /*
-- 
1.8.1.4

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