[PATCH] arm64: remove unneeded copy to init_utsname()->machine

From: Masahiro Yamada
Date: Thu Sep 14 2017 - 07:42:23 EST


As you see in init/version.c, init_uts_ns.name.machine is initially
set to UTS_MACHINE. There is no point to copy the same string.

I dug the git history to figure out why this line is here. My best
guess is like this:

- This line has been around here since the initial support of arm64
by commit 9703d9d7f77c ("arm64: Kernel booting and initialisation").
If ARCH (=arm64) and UTS_MACHINE (=aarch64) do not match,
arch/$(ARCH)/Makefile is supposed to override UTS_MACHINE, but the
initial version of arch/arm64/Makefile missed to do that. Instead,
the boot code copied "aarch64" to init_utsname()->machine.

- Commit 94ed1f2cb5d4 ("arm64: setup: report ELF_PLATFORM as the
machine for utsname") replaced "aarch64" with ELF_PLATFORM to
make "uname" to reflect the endianness.

- ELF_PLATFORM does not help to provide the UTS machine name to rpm
target, so commit cfa88c79462d ("arm64: Set UTS_MACHINE in the
Makefile") fixed it. The commit simply replaced ELF_PLATFORM with
UTS_MACHINE, but missed the fact the string copy itself is no longer
needed.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---

arch/arm64/kernel/Makefile | 2 --
arch/arm64/kernel/setup.c | 2 --
2 files changed, 4 deletions(-)

diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index f2b4e81..29764d7 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -10,8 +10,6 @@ CFLAGS_REMOVE_ftrace.o = -pg
CFLAGS_REMOVE_insn.o = -pg
CFLAGS_REMOVE_return_address.o = -pg

-CFLAGS_setup.o = -DUTS_MACHINE='"$(UTS_MACHINE)"'
-
# Object file lists.
arm64-obj-y := debug-monitors.o entry.o irq.o fpsimd.o \
entry-fpsimd.o process.o ptrace.o setup.o signal.o \
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index d4b7405..b2fdb59 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -23,7 +23,6 @@
#include <linux/stddef.h>
#include <linux/ioport.h>
#include <linux/delay.h>
-#include <linux/utsname.h>
#include <linux/initrd.h>
#include <linux/console.h>
#include <linux/cache.h>
@@ -246,7 +245,6 @@ void __init setup_arch(char **cmdline_p)
{
pr_info("Boot CPU: AArch64 Processor [%08x]\n", read_cpuid_id());

- sprintf(init_utsname()->machine, UTS_MACHINE);
init_mm.start_code = (unsigned long) _text;
init_mm.end_code = (unsigned long) _etext;
init_mm.end_data = (unsigned long) _edata;
--
2.7.4