1，配置,后面补充
2，挂死后串口抓取日志，分析日志查看打印：
[ 3.341914] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008
[ 3.350363] mmc0: SDHCI controller on fe310000.sdhci [fe310000.sdhci] using ADMA
[ 3.376962] Mem abort info:
[ 3.377859] ESR = 0x96000005
[ 3.378136] EC = 0x25: DABT (current EL), IL = 32 bits
[ 3.378615] SET = 0, FnV = 0
[ 3.378891] EA = 0, S1PTW = 0
[ 3.379167] Data abort info:
[ 3.379421] ISV = 0, ISS = 0x00000005
[ 3.379765] CM = 0, WnR = 0
[ 3.380030] [0000000000000008] user address but active_mm is swapper
[ 3.380592] Internal error: Oops: 96000005 [#1] SMP
[ 3.381028] Modules linked in:
[ 3.381310] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.10.160 #10
[ 3.381857] Hardware name: Rockchip RK3568 KICKPI K1B Board (DT)
[ 3.382384] pstate: 60c00009 (nZCv daif +PAN +UAO -TCO BTYPE=--)
[ 3.382918] pc : rfkill_wlan_probe+0x518/0x63c
[ 3.383309] lr : rfkill_wlan_probe+0x514/0x63c
[ 3.383699] sp : ffffffc00a74bb20
[ 3.383998] x29: ffffffc00a74bb20 x28: 0000000000000000
[ 3.384468] x27: ffffffc0097bf648 x26: ffffffc0097bf648
[ 3.384939] x25: ffffffc009ae6b90 x24: ffffffc00a5c05b0
[ 3.385410] x23: ffffffc00a713000 x22: ffffff8003a1fb00
[ 3.385880] x21: ffffffc0097bf4c8 x20: 0000000000000000
[ 3.386351] x19: ffffff8003435c00 x18: 0000000000000030
[ 3.386822] x17: 0000000000800d0f x16: 00000000000050ba
[ 3.387292] x15: ffffffffffffffff x14: ffffffc08a74b817
[ 3.387763] x13: 0000000000000006 x12: ffffffc00a74b81f
[ 3.388233] x11: fffffffffffca178 x10: ffffffc00a3a6a30
[ 3.388704] x9 : ffffffc0080bec14 x8 : ffffffc00a2f6a30
[ 3.389174] x7 : ffffffc00a3a6a30 x6 : 0000000000000000
[ 3.389645] x5 : 0000000000017ff4 x4 : 0000000000000000
[ 3.390115] x3 : 0000000000000000 x2 : 0000000000000000
[ 3.390586] x1 : ffffff8002f38000 x0 : 0000000000000000
[ 3.391057] Call trace:
[ 3.391279] rfkill_wlan_probe+0x518/0x63c
[ 3.391649] platform_drv_probe+0x58/0xac
[ 3.392005] really_probe+0x10c/0x510
[ 3.392328] driver_probe_device+0x74/0x15c
[ 3.392696] device_driver_attach+0xbc/0xcc
[ 3.393064] __driver_attach+0x118/0x190
[ 3.393409] bus_for_each_dev+0x74/0xd0
[ 3.393754] driver_attach+0x28/0x30
[ 3.394076] bus_add_driver+0x124/0x240
[ 3.394421] driver_register+0x7c/0x124
[ 3.394765] __platform_driver_register+0x4c/0x54
[ 3.395181] rfkill_wlan_init+0x3c/0x44
[ 3.395525] rfkill_rk_init+0x2c/0x48
[ 3.395849] do_one_initcall+0x60/0x26c
[ 3.396195] kernel_init_freeable+0x270/0x2e0
[ 3.396585] kernel_init+0x18/0x114
[ 3.396897] ret_from_fork+0x10/0x24
2，查看PC指针
查看rfkill_wlan_probe+0x518/0x63c处挂死，可以看出具体问题哦在rfkill_wlan_probe函数
3，查看代码符号表地址 nm vmlinux | grep rfkill_wlan_probe
ffffffc0094bc5c8 t rfkill_wlan_probe
4，分析代码，查看挂死在哪一行代码
lark@ubuntu:~/Public/rk356x-linux/rk356x-linux/prebuilts/gcc/linux-x86/aarch64/gcc-arm-10.3-2021.07-x86_64-aarch64-none-linux-gnu/bin$ ./aarch64-none-linux-gnu-addr2line -e ../../../../../../../rk356x-linux/kernel/vmlinux ffffffc0094bc5c8 -f -C
生成结果
rfkill_wlan_probe
rfkill-wlan.c:861
可以查看到
pdata = NULL;
if (!pdata->mregulator.power_ctrl_by_pmu)
可以看到代码pdata为空指针后继续使用。
补充：addr2line 没有抓到相应的符号表，如果查看符号表
(1) gcc/aarch64-none-linux-gnu-gcc编译的时候加上-g
(2) strip 命令从 XCOFF 对象文件中有选择地除去行号信息、重定位信息、调试段、typchk 段、注释段、文件头以及所有或部分符号表。
strip // Discard symbols from object files.
--strip-all //Remove all symbols.
--strip-debug //Remove debugging symbols only.
makefile举例说明：
package: $(EXECUTABLE)
# 保留调试信息
objcopy --only-keep-debug $(EXECUTABLE)$(DEBUGFILE)
# 剥离可执行文件中的符号信息
strip --strip-debug --strip-unneeded $(EXECUTABLE)
# 添加调试链接到可执行文件
objcopy --add-gnu-debuglink=$(DEBUGFILE)$(EXECUTABLE)