From: Arnd Bergmann <arnd@arndb.de>
Date: Wed, 16 Nov 2016 14:17:09 +0000 (+0100)
Subject: x86/boot: Avoid warning for zero-filling .bss
X-Git-Tag: v4.9.8~923^2~8
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=553bbc11aa6c1f9e0f529a06aeeca15fbe4a3985;p=platform%2Fkernel%2Flinux-rpi3.git

x86/boot: Avoid warning for zero-filling .bss

The latest binutils are warning about a .fill directive with an explicit
value in a .bss section:

  arch/x86/kernel/head_32.S: Assembler messages:
  arch/x86/kernel/head_32.S:677: Warning: ignoring fill value in section `.bss..page_aligned'
  arch/x86/kernel/head_32.S:679: Warning: ignoring fill value in section `.bss..page_aligned'

This comes from the 'ENTRY()' macro padding the space between the symbols
with 'nop' via:

  .align 4,0x90

Open-coding the .globl directive without the padding avoids that warning,
as all the symbols are already page aligned.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161116141726.2013389-1-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---

diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index b6b2f02..2dabea4 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -665,14 +665,17 @@ __PAGE_ALIGNED_BSS
 initial_pg_pmd:
 	.fill 1024*KPMDS,4,0
 #else
-ENTRY(initial_page_table)
+.globl initial_page_table
+initial_page_table:
 	.fill 1024,4,0
 #endif
 initial_pg_fixmap:
 	.fill 1024,4,0
-ENTRY(empty_zero_page)
+.globl empty_zero_page
+empty_zero_page:
 	.fill 4096,1,0
-ENTRY(swapper_pg_dir)
+.globl swapper_pg_dir
+swapper_pg_dir:
 	.fill 1024,4,0
 EXPORT_SYMBOL(empty_zero_page)