On Wed, Jul 03, 2024 at 11:44:38PM +0900, Masahiro Yamada wrote:
>On Wed, Jul 3, 2024 at 8:40 AM Wei Yang <richard.weiyang@xxxxxxxxx> wrote:
>>
>> .meminit.* is not put into init section when CONFIG_MEMORY_HOTPLUG is
>> set, since we define MEM_KEEP()/MEM_DISCARD() according to
>> CONFIG_MEMORY_HOTPLUG.
>>
>> Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>
>> CC: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
>> ---
>> scripts/mod/modpost.c | 10 ++++++++++
>> 1 file changed, 10 insertions(+)
>
>
>
>NACK.
>
>
>The section mismatch is performed _unconditionally_.
>
>
>
>In the old days, we did this depending on relevant CONFIG options.
>It was more than 15 years ago that we stopped doing that.
>
>
>See this:
>
>
>commit eb8f689046b857874e964463619f09df06d59fad
>Author: Sam Ravnborg <sam@xxxxxxxxxxxx>
>Date: Sun Jan 20 20:07:28 2008 +0100
>
> Use separate sections for __dev/__cpu/__mem code/data
>
>
>
>
>So, if you wanted to check this only when CONFIG_MEMORY_HOTPLUG=n,
>you would need to add #ifdef CONFIG_MEMORY_HOTPLUG to include/linux/init.h
>
You mean something like this?
diff --git a/include/linux/init.h b/include/linux/init.h
index 58cef4c2e59a..388f0a4c34e9 100644
--- a/include/linux/init.h
+++ b/include/linux/init.h
@@ -85,10 +85,12 @@
#define __exit __section(".exit.text") __exitused __cold notrace
/* Used for MEMORY_HOTPLUG */
+#ifndef CONFIG_MEMORY_HOTPLUG
#define __meminit __section(".meminit.text") __cold notrace \
__latent_entropy
#define __meminitdata __section(".meminit.data")
#define __meminitconst __section(".meminit.rodata")
+#endif
/* For assembly routines */
#define __HEAD .section ".head.text","ax"
>That is what we did in the Linux 2.6.* era, which had much worse
>section mismatch coverage.
>
I guess you mean this is not a good practice.
Then I am confused how we do the mismatch check unconditionally?
After commit
commit eb8f689046b857874e964463619f09df06d59fad
Author: Sam Ravnborg <sam@xxxxxxxxxxxx>
Date: Sun Jan 20 20:07:28 2008 +0100
Use separate sections for __dev/__cpu/__mem code/data
Sections .meminit.* will be put into INIT_SECTION conditionally, but we always
do the mismatch check unconditionally. It will report mismatch when .meminit.*
is not in INIT_SECTION. It looks not correct to me.
Maybe I am not fully understand your message. Would you mind explaining more
on what is the correct way to do?
--
Wei Yang
Help you, Help me
