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charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) X-Rspamd-Queue-Id: A882440011 X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: aqa1w3axe3y6y9f7mxf5jpff3rktyth9 X-HE-Tag: 1720310646-335529 X-HE-Meta: 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 yDog82OP 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.014776, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sat, Jul 06, 2024 at 10:50:25PM +0900, Masahiro Yamada wrote: >On Sat, Jul 6, 2024 at 3:12 PM Wei Yang wrote: >> >> On Fri, Jul 05, 2024 at 06:54:56AM +0000, Wei Yang wrote: >> >On Wed, Jul 03, 2024 at 11:44:38PM +0900, Masahiro Yamada wrote: >> >>On Wed, Jul 3, 2024 at 8:40 AM Wei Yang 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 >> >>> CC: Mike Rapoport (IBM) >> >>> --- >> >>> 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 >> >>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 >> >> >> >>That is what we did in the Linux 2.6.* era, which had much worse >> >>section mismatch coverage. >> >> >> > >> >Masahiro >> > >> >If you would give me some suggestions, I'd appreciate it a lot. >> > >> >The original thing I want to do is to put function __free_pages_core() in >> >__meminit section, since this function is only used by __init functions and >> >in memory_hotplug.c. This means it is save to release it if >> >CONFIG_MEMORY_HOTPLUG is set. >> > >> >Then I add __meminit to function __free_pages_core() and face the warning from >> >modpost. >> > >> > WARNING: modpost: vmlinux: section mismatch in reference: generic_online_page+0xa (section: .text) -> __free_pages_core (section: .meminit.text) >> > >> >A .text function calls init code is not proper. Then I add __meminit to >> >generic_online_page too. Then I face this warning from modpost. >> > >> > WARNING: modpost: vmlinux: generic_online_page: EXPORT_SYMBOL used for init symbol. Remove __init or EXPORT_SYMBOL. >> > >> >> I guess I found the correct way. >> >> Add __ref to generic_online_page to not issue a warning. > > > >Yes, __ref is used to bypass the section mismatch check. > I am think whether __ref is providing a gate to escape the check of modpost? >Some functions in mm/memory_hotplug.c are annotated as __ref >to reference __meminit functions. > >Adding __ref is the easy solution. > > > >Having said that, I started to think >eb8f689046b857874e964463619f09df06d59fad was the wrong decision. >I will revert it. > Oh, I finally understand it... didn't think that was a wrong decision :-( > > > > > > > > > > >-- >Best Regards >Masahiro Yamada -- Wei Yang Help you, Help me