linux - Is __init attribute used in loadable kernel modules? -

the description @ - http://www.tldp.org/ldp/lkmpg/2.4/html/x281.htm - page (as related answers on so, example answer here - __init , __exit macros usage built-in , loadable modules ) says

the __init macro causes init function discarded , memory freed once init function finishes built-in drivers, not loadable modules.

however, tried insert following module, in try call init functions __init attribute non-init function (f2()), , error kernel, indicating __init has effect on loadable modules well.

how , can find reliable information this?

my (above mentioned) program:

#include<linux/module.h> #include<linux/init.h>  static int __init f1(void){         printk(kern_alert "hello  \n");         return 0; }   static void __exit f2(void){         f1();         printk(kern_alert "bye n\n"); }  module_init(f1); module_exit(f2); 

error kernel:

    jul  8 08:15:51 localhost kernel: hello notice      jul  8 08:15:54 localhost kernel: [303032.948188] bug: unable handle kernel paging request @ f9b13000     jul  8 08:15:54 localhost kernel: [303032.949003] ip: [<f9b13000>] 0xf9b12fff     jul  8 08:15:54 localhost kernel: [303032.949003] *pdpt = 0000000000d3c001 *pde = 000000003100b067 *pte = 0000000000000000   jul  8 08:15:54 localhost kernel: [303032.949003] modules linked in: hello(pof-) tcp_lp lp wacom fuse bnep bluetooth ip6t_rpfilter ip6t_reject cfg80211 rfkill xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw joydev snd_hda_codec_realtek snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device snd_pcm coretemp kvm itco_wdt itco_vendor_support ppdev r8169 mii snd_page_alloc snd_timer snd soundcore microcode serio_raw i2c_i801 lpc_ich mfd_core parport_pc parport acpi_cpufreq mperf binfmt_misc nfsd auth_rpcgss nfs_acl lockd sunrpc i915 ata_generic i2c_algo_bit pata_acpi drm_kms_helper drm i2c_core video [last unloaded: hello] jul  8 08:15:54 localhost kernel: [303032.949003] cpu: 1 pid: 11924 comm: rmmod tainted: pf          o 3.11.10-301.fc20.i686+pae #1 jul  8 08:15:54 localhost kernel: [303032.949003] hardware name:                  /dg41rq, bios rqg4110h.86a.0013.2009.1223.1136 12/23/2009 jul  8 08:15:54 localhost kernel: [303032.949003] task: d1bad780 ti: c33a4000 task.ti: c33a4000 jul  8 08:15:54 localhost kernel: [303032.949003] eip: 0060:[<f9b13000>] eflags: 00010282 cpu: 1 jul  8 08:15:54 localhost kernel: [303032.949003] eip @ 0xf9b13000 jul  8 08:15:54 localhost kernel: [303032.949003] eax: f9af6000 ebx: f9af8000 ecx: c0c77270 edx: 00000000 jul  8 08:15:54 localhost kernel: [303032.949003] esi: 00000000 edi: 00000000 ebp: c33a5f3c esp: c33a5f30 jul  8 08:15:54 localhost kernel: [303032.949003]  ds: 007b es: 007b fs: 00d8 gs: 00e0 ss: 0068 jul  8 08:15:54 localhost kernel: [303032.949003] cr0: 8005003b cr2: f9b13000 cr3: 10e7b000 cr4: 000407f0 jul  8 08:15:54 localhost kernel: [303032.949003] stack: jul  8 08:15:54 localhost kernel: [303032.949003]  f9af600b 00000000 00000000 c33a5fac c04b06a9 f4852ac0 c33a5f50 c057989d jul  8 08:15:54 localhost kernel: [303032.949003]  00000000 f9af8000 00000800 c33a5f50 6c6c6568 0000006f f4852ac0 f5312490 jul  8 08:15:54 localhost kernel: [303032.949003]  db5e7100 00000000 d1bad780 d1bada9c c33a5f88 c056160d c33a5f9c c046e9de jul  8 08:15:54 localhost kernel: [303032.949003] call trace: jul  8 08:15:54 localhost kernel: [303032.949003]  [<f9af600b>] ? f2+0xb/0x1000 [hello] jul  8 08:15:54 localhost kernel: [303032.949003]  [<c04b06a9>] sys_delete_module+0x149/0x2a0 jul  8 08:15:54 localhost kernel: [303032.949003]  [<c057989d>] ? mntput+0x1d/0x30 jul  8 08:15:54 localhost kernel: [303032.949003]  [<c056160d>] ? ____fput+0xd/0x10 jul  8 08:15:54 localhost kernel: [303032.949003]  [<c046e9de>] ? task_work_run+0x7e/0xb0 jul  8 08:15:54 localhost kernel: [303032.949003]  [<c099ff0d>] sysenter_do_call+0x12/0x28 jul  8 08:15:54 localhost kernel: [303032.949003] code:  bad eip value. jul  8 08:15:54 localhost kernel: [303032.949003] eip: [<f9b13000>] 0xf9b13000 ss:esp 0068:c33a5f30 jul  8 08:15:54 localhost kernel: [303032.949003] cr2: 00000000f9b13000 jul  8 08:15:54 localhost kernel: [303032.949003] ---[ end trace ca338922043618f4 ]--- jul  8 08:15:54 localhost kernel: bug: unable handle kernel paging request @ f9b13000 jul  8 08:15:54 localhost kernel: ip: [<f9b13000>] 0xf9b12fff jul  8 08:15:54 localhost kernel: *pdpt = 0000000000d3c001 *pde = 000000003100b067 *pte = 0000000000000000  

actually, __init attribute affects on loadable modules code.

probably, misprint in book refers.

btw, should warning sections mismatching when build given module.