acassis commented on code in PR #12631:
URL: https://github.com/apache/nuttx/pull/12631#discussion_r1667397827
##########
Documentation/components/binfmt.rst:
##########
@@ -349,6 +349,83 @@ Symbol Table Function Interfaces
A reference to the symbol table entry if an entry with the matching
value is found; ``NULL`` is returned if the entry is not found.
+Debugging of ELF module
+=======================
+
+To implement ELF module debugging in NuttX, the GDB JIT (Just-In-Time)
interface is utilized. This interface resembles that of a dynamic loader. The
JIT compiler communicates with GDB by writing data to a global variable and
invoking a specific symbol's function. When GDB attaches to the program, it
reads a linked list of symbol files from the global variable to locate existing
code and sets breakpoints in functions to monitor additional code.
+Based on the aforementioned principle, during ELF file loading, file-related
information (filename, text address, data address) is written. This information
is communicated to the PC-side GDB through __loadable_module_register_code
function. The PC-side GDB debugs the ELF program by setting breakpoints.
+
+CONFIG
+------
+
+.. code-block:: c
+
+ CONFIG_ELF=y
+ CONFIG_LOADABLE_MODULE_DEBUG=y
+ CONFIG_LOADABLE_MODULE_DESCRIPTOR_COUNT=7 (default value)
+
+Symbol Table Header Files
+-------------------------
+
+The export interface to the ELF Module load/unload in debug mode is described
in the header file
+``include/nuttx/binfmt/binfmt.h``.
+A brief summary of the data structurs (data type) and interfaces prototyped
are listed below.
+
+ELF Module Data Type in Debug Mode
+----------------------------------
+
+.. c:enum:: loadable_module_actions_t
+
+ Describes the registered status of an ELF module in debug mode.
+
+ .. code-block:: c
+
+ typedef enum
+ {
+ LOADABLE_MODULE_NOACTION = 0,
+ LOADABLE_MODULE_REGISTER_FN, /* A ELF is registered */
+ LOADABLE_MODULE_UNREGISTER_FN /* A ELF is unregistered */
+ } loadable_module_actions_t;
+
+ELF Module Data Structures in Debug Mode
+----------------------------------------
+
+.. c:struct:: loadable_module_descriptor
+
+ Describe some information about an ELF module in debug mode.
+
+ .. code-block:: c
+
+ struct loadable_module_descriptor
+ {
+ uint32_t action_flag; /* Whether ELF is loaded with registered flags
by loadable_module_actions_t enum type*/
+ const char *symfile_name; /* A pointer to the ELF Module file name
string */
+ void *text_addr; /* A pointer to the text address segment of
the ELF file */
+ void *data_addr; /* A pointer to the data address segment of
the ELF file */
+ };
+
+
+ELF Module Interfaces in Debug Mode
+-----------------------------------
+
+The implementation of the ELF module loading/unloading interface in debug mode
is described in the c file
+``binfmt/binfmt_debug.c``.
+
+.. c:function:: bool loadable_module_create(const char *symfile_name, void
*text_addr,
Review Comment:
I think you can keep it as a single line here to avoid the CI error
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