On 2021/6/7 13:48, Christophe Leroy wrote:
Hi Kefeng,
Le 07/06/2021 à 02:55, Kefeng Wang a écrit :
On 2021/6/7 5:29, Mike Rapoport wrote:
Hello Kefeng,
On Fri, Jun 04, 2021 at 03:06:18PM +0800, Kefeng Wang wrote:
Add setup_initial_init_mm() helper, then use it
to cleanup the text, data and brk setup code.
v2:
- change argument from "char *" to "void *" setup_initial_init_mm()
suggested by Geert Uytterhoeven
- use NULL instead of (void *)0 on h8300 and m68k
- collect ACKs
Cc: linux-snps-arc@xxxxxxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-csky@xxxxxxxxxxxxxxx
Cc: uclinux-h8-devel@xxxxxxxxxxxxxxxxxxxx
Cc: linux-m68k@xxxxxxxxxxxxxxxxxxxx
Cc: openrisc@xxxxxxxxxxxxxxxxxxxx
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Cc: linux-riscv@xxxxxxxxxxxxxxxxxxx
Cc: linux-sh@xxxxxxxxxxxxxxx
Cc: linux-s390@xxxxxxxxxxxxxxx
Kefeng Wang (15):
mm: add setup_initial_init_mm() helper
arc: convert to setup_initial_init_mm()
arm: convert to setup_initial_init_mm()
arm64: convert to setup_initial_init_mm()
csky: convert to setup_initial_init_mm()
h8300: convert to setup_initial_init_mm()
m68k: convert to setup_initial_init_mm()
nds32: convert to setup_initial_init_mm()
nios2: convert to setup_initial_init_mm()
openrisc: convert to setup_initial_init_mm()
powerpc: convert to setup_initial_init_mm()
riscv: convert to setup_initial_init_mm()
s390: convert to setup_initial_init_mm()
sh: convert to setup_initial_init_mm()
x86: convert to setup_initial_init_mm()
I might be missing something, but AFAIU the init_mm.start_code and
other
fields are not used really early so the new setup_initial_init_mm()
function can be called in the generic code outside setup_arch(), e.g in
mm_init().
Hi Mike， each architecture has their own value, not the same, eg m68K
and
h8300, also the name of the text/code/brk is different in some arch,
so I keep
unchanged.
What you could do is to define a __weak function that architectures
can override and call that function from mm_init() as suggested by Mike,
Something like:
void __weak setup_initial_init_mm(void)
{
init_mm.start_code = (unsigned long)_stext;
init_mm.end_code = (unsigned long)_etext;
init_mm.end_data = (unsigned long)_edata;
init_mm.brk = (unsigned long)_end;
}
Then only the few architecture that are different would override it.
I see a few archictectures are usigne PAGE_OFFSET to set .start_code,
but it is likely that this is equivalent to _stext.
Yes, the __weak function is option, but the change is only covered 14
archs, there are 7 other archs（alpha hexagon ia64
microblaze mips sparc um xtensa）without related setup code. Also like
x86, it has own brk , maybe there are some
other different in some arch, so I think let's keep unchanged for now,
thanks.
Christophe
.
