[PATCH 1/2] x86/head_64.S: Rename start_cpu()

From: Borislav Petkov
Date: Sat Mar 04 2017 - 04:56:39 EST


From: Borislav Petkov <bp@xxxxxxx>

It doesn't really start a CPU but does a far jump to C code. So call it
that. Eliminate the unconditional JMP to it from secondary_startup_64()
but make the jump to C code piece part of secondary_startup_64()
instead.

Also, it doesn't need to be a global symbol either so make it a local
label. One less needlessly global symbol in the symbol table.

No functionality change.

Signed-off-by: Borislav Petkov <bp@xxxxxxx>
---
arch/x86/kernel/head_64.S | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index b467b14b03eb..ac9d327d2e42 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -269,10 +269,8 @@ ENTRY(secondary_startup_64)
/* rsi is pointer to real mode structure with interesting info.
pass it to C */
movq %rsi, %rdi
- jmp start_cpu
-ENDPROC(secondary_startup_64)

-ENTRY(start_cpu)
+.Ljump_to_C_code:
/*
* Jump to run C code and to be on a real kernel address.
* Since we are running on identity-mapped space we have to jump
@@ -305,7 +303,7 @@ ENTRY(start_cpu)
pushq %rax # target address in negative space
lretq
.Lafter_lret:
-ENDPROC(start_cpu)
+ENDPROC(secondary_startup_64)

#include "verify_cpu.S"

@@ -313,11 +311,11 @@ ENDPROC(start_cpu)
/*
* Boot CPU0 entry point. It's called from play_dead(). Everything has been set
* up already except stack. We just set up stack here. Then call
- * start_secondary() via start_cpu().
+ * start_secondary() via .Ljump_to_C_code.
*/
ENTRY(start_cpu0)
movq initial_stack(%rip), %rsp
- jmp start_cpu
+ jmp .Ljump_to_C_code
ENDPROC(start_cpu0)
#endif

--
2.11.0