Re: [ammarfaizi2-block:paulmck/linux-rcu/fastexp.2022.04.01a 109/158] WARNING: modpost: vmlinux.o(.text+0xbcac06): Section mismatch in reference from the function ieee802154_iface_init() to the variable .init.text:.L0

["Paul E. McKenney" <paulmck@kernel.org>]

On Mon, Apr 04, 2022 at 12:20:22AM +0800, kernel test robot wrote:
> tree:   https://github.com/ammarfaizi2/linux-block paulmck/linux-rcu/fastexp.2022.04.01a
> head:   d9f3e7d671416fdf5b61f094765754269b652db0
> commit: c1468fd1496363a0b2b2cb89e8ec2ba5e1dce9ba [109/158] rcu: Add polled expedited grace-period primitives
> config: riscv-randconfig-r002-20220403 (https://download.01.org/0day-ci/archive/20220404/202204040012.4Fu9uBps-lkp@intel.com/config)
> compiler: riscv32-linux-gcc (GCC) 11.2.0
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # https://github.com/ammarfaizi2/linux-block/commit/c1468fd1496363a0b2b2cb89e8ec2ba5e1dce9ba
>         git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block
>         git fetch --no-tags ammarfaizi2-block paulmck/linux-rcu/fastexp.2022.04.01a
>         git checkout c1468fd1496363a0b2b2cb89e8ec2ba5e1dce9ba
>         # save the config file to linux build tree
>         mkdir build_dir
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=riscv SHELL=/bin/bash
> 
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
> 
> All warnings (new ones prefixed by >>, old ones prefixed by <<):
> 
> >> WARNING: modpost: vmlinux.o(.text+0xbcac06): Section mismatch in reference from the function ieee802154_iface_init() to the variable .init.text:.L0
> The function ieee802154_iface_init() references
> the variable __init .L0 .
> This is often because ieee802154_iface_init lacks a __init
> annotation or the annotation of .L0 is wrong.
> 
> Note: the below error/warnings can be found in parent commit:
> << WARNING: modpost: vmlinux.o(.text+0x432e6): Section mismatch in reference from the function dma_get_required_mask() to the variable .init.text:.L0
> << WARNING: modpost: vmlinux.o(.text+0xe35ca): Section mismatch in reference from the function mlock_page_drain() to the variable .init.text:.LVL125
> << WARNING: modpost: vmlinux.o(.text+0x96a46e): Section mismatch in reference from the function rpmsg_create_ept() to the variable .init.text:.L0
> << WARNING: modpost: vmlinux.o(.text+0x96a5b4): Section mismatch in reference from the function rpmsg_destroy_ept() to the variable .init.text:.L0
> << WARNING: modpost: vmlinux.o(.text+0x96a5c0): Section mismatch in reference from the function rpmsg_send() to the variable .init.text:.L0
> << WARNING: modpost: vmlinux.o(.text+0x96a5d4): Section mismatch in reference from the function rpmsg_sendto() to the variable .init.text:.L0
> << WARNING: modpost: vmlinux.o(.text+0x96a5e8): Section mismatch in reference from the function rpmsg_send_offchannel() to the variable .init.text:.L0
> << WARNING: modpost: vmlinux.o(.text+0x96a5fc): Section mismatch in reference from the function rpmsg_trysend() to the variable .init.text:.L0
> << WARNING: modpost: vmlinux.o(.text+0x96a610): Section mismatch in reference from the function rpmsg_trysendto() to the variable .init.text:.L0
> << WARNING: modpost: vmlinux.o(.text+0x96a624): Section mismatch in reference from the function rpmsg_poll() to the variable .init.text:.L0

I freely confess that I have no idea what any of these error messages
are trying to tell me.  What is ".init.txt.L0"?  How did my patch affect
ieee802154_iface_init() or the register_netdevice_notifier() function
that it invokes?  For that matter, how did my patch cause an access to
be made to __init data from a non-__init function?

							Thanx, Paul