Re: [PATCH] ARM: Fix zImage file size not aligned with CONFIG_EFI_STUB enabled

From: jeffy
Date: Tue Oct 24 2017 - 05:16:29 EST


Hi guys,

On 10/24/2017 04:09 PM, Ard Biesheuvel wrote:
The following patch appears to fix the issue as well:

diff --git a/arch/arm/boot/compressed/vmlinux.lds.S
b/arch/arm/boot/compressed/vmlinux.lds.S
index 7a4c59154361..0e0f504e256e 100644
--- a/arch/arm/boot/compressed/vmlinux.lds.S
+++ b/arch/arm/boot/compressed/vmlinux.lds.S
@@ -83,7 +83,9 @@ SECTIONS
__pecoff_data_rawsize = . - ADDR(.data);
#endif

- _edata = .;
+ .edata (NOLOAD) : {
+ _edata = .;
+ }

_magic_sig = ZIMAGE_MAGIC(0x016f2818);
_magic_start = ZIMAGE_MAGIC(_start);

because the NOLOAD triggers the linker to emit all PROGBITS sections
before _edata, including unknown ones.

E.g., in my binary, it gives me

00798020 D __pecoff_data_end
00798200 d __ksymtab_sort
00798208 B __bss_start
00798208 D _edata

this works too:

+++ b/arch/arm/boot/compressed/vmlinux.lds.S
@@ -70,10 +70,6 @@ SECTIONS
.got : { *(.got) }
_got_end = .;

- /* ensure the zImage file size is always a multiple of 64 bits */
- /* (without a dummy byte, ld just ignores the empty section) */
- .pad : { BYTE(0); . = ALIGN(8); }
-
#ifdef CONFIG_EFI_STUB
.data : ALIGN(4096) {
__pecoff_data_start = .;
@@ -93,7 +89,10 @@ SECTIONS
__pecoff_data_rawsize = . - ADDR(.data);
#endif

- _edata = .;
+ /* ensure the zImage file size is always a multiple of 64 bits */
+ .edata : ALIGN(8) {
+ _edata = .;
+ }



339: 006cf200 8 OBJECT LOCAL DEFAULT 9 __ksymtab_sort
...
528: 006cf208 0 NOTYPE GLOBAL DEFAULT 9 _edata