lkml.org 
[lkml]   [2016]   [Aug]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH v3 3/4] arm64: kaslr: Fix incorrect placement of __initdata and __read_mostly
Hi Ard,

On Fri, 12 Aug 2016 14:02:40 +0200 Ard Biesheuvel wrote:

> Hi Jisheng,
>
> On 12 August 2016 at 10:01, Jisheng Zhang <jszhang@marvell.com> wrote:
> > __initdata and __read_mostly should be placed after the variable name
> > for the variable to be placed in the intended section.
> >
>
> Why?

include/linux/init.h says something as:

* For initialized data:
* You should insert __initdata or __initconst between the variable name
* and equal sign followed by value, e.g.:
*
* static int init_variable __initdata = 0;
* static const char linux_logo[] __initconst = { 0x32, 0x36, ... };

and examples in gcc manual also put __attribute__ (...) after variable name.

https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#Common-Variable-Attributes

Then I grep the source, found most lines (especially arch/arm64/*) put the
__initdata and __read_mostly after the variable name.

However, I built the code with three different gcc, the result looks identical
no matter where these markers put. So the commit msg looks wrong, what about
changes it as

"put __initdata and __read_mostly after the variable name
to keep the style consistent"?

Thanks,
Jisheng

>
> > Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
> > ---
> > arch/arm64/kernel/kaslr.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/arm64/kernel/kaslr.c b/arch/arm64/kernel/kaslr.c
> > index b054691..8ebabc4 100644
> > --- a/arch/arm64/kernel/kaslr.c
> > +++ b/arch/arm64/kernel/kaslr.c
> > @@ -20,8 +20,8 @@
> > #include <asm/pgtable.h>
> > #include <asm/sections.h>
> >
> > -u64 __read_mostly module_alloc_base;
> > -u16 __initdata memstart_offset_seed;
> > +u64 module_alloc_base __read_mostly;
> > +u16 memstart_offset_seed __initdata;
> >
> > static __init u64 get_kaslr_seed(void *fdt)
> > {
> > --
> > 2.8.1
> >
> >
> > _______________________________________________
> > linux-arm-kernel mailing list
> > linux-arm-kernel@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

\
 
 \ /
  Last update: 2016-09-17 09:56    [W:0.070 / U:0.408 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site