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Date: Sat, 2 May 2020 20:29:43 +0200
From: Marek Behun <marek.behun@nic.cz>
Subject: Re: [PATCH kbuild RFC] kbuild: fix modpost throwing away module
 symvers when linking vmlinux.o
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Cc: Masahiro Yamada <masahiroy@kernel.org>, Michal Marek <michal.lkml@markovi.net>

Just to note how this breaks things:

On OpenWRT this may happen
1. make modules is run
   - Module.symvers contains symbols from modules
2. make Image/bzImage is run (as part of another OpenWRT make target)
   - Module.symvers is rewritten to contain only vmlinux.o symbols
3. external kernel modules try to build (wireguard, mac80211)
   - this now fails because external modules may depend on symbols from
     other modules and this information isn't in Module.symvers anymore

Marek