http://blog.sina.com.cn/s/blog_53931eca01015uky.html
在開發kernel driver時，總是會遇到討人厭的vermagic檢查，只要目前在run的kernel版本跟driver編譯時用的kernel版本不一致，就沒辦法insmod。
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bash-3.2# insmod sdio.ko
sdio: version magic '2.6.28-271-gec75a15 preempt mod_unload modversions ARMv7 '
should be '2.6.28 preempt mod_unload ARMv7 '
insmod: init_module 'sdio.ko' failed (Exec format error)
這大大降低了開發速度，尤其是當你拿不到客戶在用的kernel時，又要開發driver給他用，真的是很麻煩……
那麼要怎麼利用噁心的方式繞過去呢???
一、先把 Moudle version 檢查關掉。
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user@host # ARCH=arm make menuconfig
--- Enable loadable module support │ │
│ │ [ ] Forced module loading │ │
│ │ [*] Module unloading │ │
│ │ [*] Forced module unloading │ │
│ │ [ ] Module versioning support │ │
│ │ [ ] Source checksum for all modules
二、 使用modinfo時，可以看到目前這driver的vermagic
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filename: external_drivers/omap3530/Linux/sdio/sdio.ko
author: Texas Instruments Inc
alias: TIWLAN_SDIO
license: GPL
description: TI WLAN SDIO driver
depends:
vermagic: 2.6.28-271-gec75a15 preempt mod_unload ARMv7
parm: g_sdio_debug_level:debug level (int)
三、 修改 kernel 的 vermagic，再重新編譯driver
vermagic 的第一個值 2.6.28-noneed 是由這 include/linux/utsrelease.h裡的 UTS_RELEASE 所定義。
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#define UTS_RELEASE "2.6.28-271-gec75a15"
之後再由 include/linux/vermagic.h 裡的 macro
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#include <generated/utsrelease.h>
#ifdef CONFIG_SMP
#define MODULE_VERMAGIC_SMP "SMP "
#else
#define MODULE_VERMAGIC_SMP ""
#endif
#ifdef CONFIG_PREEMPT
#define MODULE_VERMAGIC_PREEMPT "preempt "
#else
#define MODULE_VERMAGIC_PREEMPT ""
#endif完成編譯後，你就可以得
#ifdef CONFIG_MODULE_UNLOAD
#define MODULE_VERMAGIC_MODULE_UNLOAD "mod_unload "
#else
#define MODULE_VERMAGIC_MODULE_UNLOAD ""
#endif
#ifndef CONFIG_MODVERSIONS
#define MODULE_VERMAGIC_MODVERSIONS "modversions "
#else
#define MODULE_VERMAGIC_MODVERSIONS ""
#endif
#ifndef MODULE_ARCH_VERMAGIC
#define MODULE_ARCH_VERMAGIC ""
#endif
#define VERMAGIC_STRING \
UTS_RELEASE " " \
MODULE_VERMAGIC_SMP MODULE_VERMAGIC_PREEMPT \
MODULE_VERMAGIC_MODULE_UNLOAD MODULE_VERMAGIC_MODVERSIONS \
MODULE_ARCH_VERMAGIC
所以， 我們只要把 UTS_RELEASE 改成我們的數字即可，當然若是懶得去try組合後的字串，也可以直接將VERMAGIC_STRING改成你要的字串
建議修改完 vermagic.h, utsrelease.h後，還是把kernel重編完再編kernel，比較保險。
以下是修改後，用modinfo看的結果
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filename: external_drivers/omap3530/Linux/sdio/sdio.ko
author: Texas Instruments Inc
alias: TIWLAN_SDIO
license: GPL
description: TI WLAN SDIO driver
depends:
vermagic: 2.6.28 preempt mod_unload ARMv7
parm: g_sdio_debug_level:debug level (int)
另外若你是用git 做版本控制 , 那就會出現git的版本號在kernel 編號上
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General setup --->
[ ] Automatically append version information to the version strin
解釋;
CONFIG_LOCALVERSION_AUTO: │
│ │
│ This will try to automatically determine if the current tree is a │
│ release tree by looking for git tags that belong to the current │
│ top of tree revision. │
│ │
│ A string of the format -gxxxxxxxx will be added to the localversion │
│ if a git-based tree is found. The string generated by this will be │
│ appended after any matching localversion* files, and after the value │
│ set in CONFIG_LOCALVERSION. │
│ │
│ (The actual string used here is the first eight characters produced │
│ by running the command: │
│ │
│ which is done within the script "scripts/setlocalversion".) │
│ │
│ Symbol: LOCALVERSION_AUTO [=y] │
│ Prompt: Automatically append version information to the version string │
│ Defined at init/Kconfig:84 │
│ Location: │
│ ingT
