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--- mywiki:linux:linux_debugging_with_lauterbach [2015/12/29 17:38] – [Load System via networking] super
+++ mywiki:linux:linux_debugging_with_lauterbach [2019/09/15 18:55] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
-**Linux Debugging with LauterBach**
+**Linux Debugging**
-====== Basic requirement ======
+^ Reference | {{:mywiki:linux:linux_debugging_techniques.ppt|}} |
+====== Linux Debugging with LauterBach ======
+===== Basic requirement =====
 In order to support c source code level debugging, it is a must to enable debugging option during compile
-===== Get source code directory base =====
+==== Get source code directory base ====
-<file>
+<file C>
     mips-openwrt-linux-objdump -g vmlinux | grep -i DW_AT_comp_dir | grep -i indirect |  grep '\/'
 </file>
@@ Line 16: / Line 20: @@
     <bb2043>   DW_AT_comp_dir : (indirect string, offset: 0x171): /disk/fs1/tmp2/openwrt/core/kernel_tree
 </file>
-===== Discover entry point in ELF =====
+==== Discover entry point in ELF ====
     * Discover vmlinux entry point
 <file>
@@ Line 30: / Line 34: @@
 Its output in my setup: **start address 0x6002df00**
+==== Generate system.map ====
-===== Generate system.map =====
 <file>
     mips-openwrt-linux-nm -n vmlinux | grep -v '\( [aNUw] \)\|\(__crc_\)\|\( \$[adt]\)' > System.map
@@ Line 45: / Line 44: @@
 </file>
-====== Lauterbach/Debugger ======
+===== Lauterbach/Debugger =====
-===== Load System via networking =====
+==== Load symbol from linux PC via networking ====
 Suppose below working environment:
-| Linux Compilation folder | /disk/fs1/tmp2/shaoguoh/project/ugw61_grx500/openwrt/core/kernel_tree |
+| Linux Compilation folder via [[linux_debugging_with_lauterbach#get_source_code_directory_base|method]] | /disk/fs1/tmp2/shaoguoh/project/ugw61_grx500/openwrt/core/kernel_tree |
 | vmlinux folder | /disk/fs1/tmp2/shaoguoh/project/ugw61_grx500/openwrt/core/kernel_tree |
 | samba mapping folder to windows | X:\tmp2\shaoguoh\project\ugw61_grx500\openwrt\core\kernel_tree |
@@ Line 55: / Line 54: @@
 Lauterbach command:
 <file>
-  d.load.elf X:\tmp2\shaoguoh\project\ugw61_grx500\openwrt\core\kernel_tree\vmlinux /strippart "/disk/fs1/tmp2" /path "X:\tmp2" /nocode
+  d.load.elf "X:\tmp2\shaoguoh\project\ugw61_grx500\openwrt\core\kernel_tree\vmlinux" /strippart "/disk/fs1/tmp2" /path "X:\tmp2" /nocode
 </file>
@@ Line 63: / Line 62: @@
   * /nocode: don't load code, but symbol only
-Example:
+**Example**:
-If there is one file name in vmlinux:
+If the location of one file in vmlinux debugging as below:
     /disk/fs1/tmp2/shaoguoh/project/ugw61_grx500/openwrt/core/kernel_tree/t.c
-After /strippart "/disk/fs1/tmp2", it become:
+After /strippart "/disk/fs1/tmp2", ie, strip the prefix as specified here, it become:
     shaoguoh/project/ugw61_grx500/openwrt/core/kernel_tree/t.c
-After  /path "X:\tmp2", it become:
+After  /path "X:\tmp2", ie, add prefix as specified here, it become:
     X:\tmp2\shaoguoh/project/ugw61_grx500/openwrt/core/kernel_tree/t.c
+With this folder, now debugger can access this file via samba from windows
+====== Linux Kernel Debugging Tools ======
+===== Enable kernel debug to detection lock/context issue =====
+In openwrt/core, run: make kernel_menuconfig
+In kernel_hack, enable below items:
+{{:mywiki:linux:kernel_hack.jpg|}}