linux驱动调试--段错误之oops信息分析 http://blog.chinaunix.net/xmlrpc.php?r=blog/article&uid=29401328&id=4923447
如：
Unable to handle kernel paging request at virtual address 48000000 // 内核使用48000000来访问时发生了错误 pgd = c3b4c000 [48000000] *pgd=00000000 Internal error: Oops: 805 [#1] Modules linked in: first_drv rt5370sta zd1211rw mac80211 CPU: 0 Not tainted (2.6.30.4-EmbedSky #1) PC is at segment_test_open+0x1c/0x28 [first_drv] // PC值 LR is at chrdev_open+0xcc/0x170 pc : [] lr : [] psr: a0000013 // 发生错误时各寄存器的值（下面五行） sp : c3a61e30 ip : c3a61e40 fp : c3a61e3c r10: c394bc80 r9 : 00000002 r8 : c34b7600 r7 : c3b46100 r6 : c3ab84b0 r5 : c3a62180 r4 : 00000000 r3 : 00000034 r2 : 48000000 r1 : c3b46100 r0 : 00000000 Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: c000717f Table: 33b4c000 DAC: 00000015 Process firstdrvtest (pid: 637, stack limit = 0xc3a60268) // 发生错误时当前进程的名称是firstdrvtest Stack: (0xc3a61e30 to 0xc3a62000) // 栈 1e20: c3a61e64 c3a61e40 c00a8580 bf0d7010 1e40: c00adba8 00000000 00000000 c3b46100 c3ab84b0 c00a84b4 c3a61e8c c3a61e68 1e60: c00a3a7c c00a84c4 c3b46100 c2c0ae40 00000003 c3af0000 00000026 c3a61ed8 1e80: c3a61eac c3a61e90 c00a3d14 c00a39bc 00000000 c2c0ae40 00000000 00000000 1ea0: c3a61f64 c3a61eb0 c00b0c80 c00a3cc0 c3a61f7c c3a61ec0 c004b714 c006f8b8 1ec0: c3a61efc beb5ad9c 00000000 00000000 c3a63000 c048070c c394bc80 c34b7600 1ee0: c048077c c3a61fb0 00000000 00000101 00000001 00000000 c00441e0 c004b548 1f00: 08100875 c39568a0 c3a7ec00 0000001c 00000000 00001000 00000003 00000003 1f20: 00000000 c3b46100 00000000 c3a60000 c3a61f64 c3a61f40 c00b99b8 00000003 1f40: c3af0000 00000002 beb5ad9c ffffff9c c3a60000 00000000 c3a61f94 c3a61f68 1f60: c00a38d8 c00b0aa0 00000000 40025000 c3a61f9c 0000850c 00000000 000083e0 1f80: 00000005 c0045008 c3a61fa4 c3a61f98 c00a3988 c00a3878 00000000 c3a61fa8 1fa0: c0044e60 c00a3974 0000850c 00000000 00008590 00000002 beb5ad9c 00000001 1fc0: 0000850c 00000000 000083e0 00000005 00000000 00000000 40025000 beb5ac44 1fe0: 00000000 beb5ac28 000084b8 400efd9c 60000010 00008590 00000000 00000000 Backtrace: // 回溯信息 [] (segment_test_open+0x0/0x28 [first_drv]) from [] (chrdev_open+0xcc/0x170) [] (chrdev_open+0x0/0x170) from [] (__dentry_open+0xd0/0x270) r7:c00a84b4 r6:c3ab84b0 r5:c3b46100 r4:00000000 [] (__dentry_open+0x0/0x270) from [] (nameidata_to_filp+0x64/0x6c) [] (nameidata_to_filp+0x0/0x6c) from [] (do_filp_open+0x1f0/0x7e8) r5:00000000 r4:00000000 [] (do_filp_open+0x0/0x7e8) from [] (do_sys_open+0x70/0xe8) [] (do_sys_open+0x0/0xe8) from [] (sys_open+0x24/0x28) r8:c0045008 r7:00000005 r6:000083e0 r5:00000000 r4:0000850c [] (sys_open+0x0/0x28) from [] (ret_fast_syscall+0x0/0x2c) Code: e59f3010 e3a00000 e5932000 e3a03034 (e5c23000) ---[ end trace d31b8aee70b25c9c ]--- Segmentation fault
一、直接确定发生错误的函数
看到这句 “PC is at segment_test_open+0x1c/0x28 [first_drv]”，出现错误时我们最关注的就是PC值，因为它就是发生错误的指令的地址，这里我们可以看到错误发生在函数 segment_test_open 的0x1c处，0x28代表这个函数的总长度（汇编代码）
二、根据PC值确定发生错误的函数
有时候不会直接告诉你发生在哪个函数，而是只把PC值告诉你。。。这种比较复杂，见参考链接。
linux设备驱动第四篇：从如何定位oops的代码行谈驱动调试方法 http://blog.csdn.net/haomcu/article/details/44810709
在这个例子里面，还可以使用addr2line直接定位到具体代码行。
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffffc061400d>] hello_init+0xd/0x30 [helloworld]</span>
addr2line -C -f -e helloworld.o d
Linux内核的Oops http://www.cnblogs.com/wwang/archive/2010/11/14/1876735.html