Re: [PATCH] scripts/gdb: fix usage of MOD_TEXT not defined when CONFIG_MODULES=n

From: Daniel Gomez
Date: Fri Aug 18 2023 - 10:50:53 EST


Hi,
On Tue, Aug 01, 2023 at 02:57:15PM +0200, Clément Léger wrote:
> MOD_TEXT is only defined if CONFIG_MODULES=y which lead to loading failure
> of the gdb scripts when kernel is built without CONFIG_MODULES=y:
>
> Reading symbols from vmlinux...
> Traceback (most recent call last):
> File "/foo/vmlinux-gdb.py", line 25, in <module>
> import linux.constants
> File "/foo/scripts/gdb/linux/constants.py", line 14, in <module>
> LX_MOD_TEXT = gdb.parse_and_eval("MOD_TEXT")
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> gdb.error: No symbol "MOD_TEXT" in current context.
>
> Add a conditional check on CONFIG_MODULES to fix this error.
>
> Fixes: b4aff7513df3 ("scripts/gdb: use mem instead of core_layout to get the module address")
> Signed-off-by: Clément Léger <cleger@xxxxxxxxxxxx>

I've hit the same issue. After rebasing onto next-20230818 we'd need:

diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in
index e3517d4ab8ec..04c87b570aab 100644
--- a/scripts/gdb/linux/constants.py.in
+++ b/scripts/gdb/linux/constants.py.in
@@ -66,10 +66,11 @@ LX_GDBPARSED(IRQD_LEVEL)
LX_GDBPARSED(IRQ_HIDDEN)

/* linux/module.h */
-LX_GDBPARSED(MOD_TEXT)
-LX_GDBPARSED(MOD_DATA)
-LX_GDBPARSED(MOD_RODATA)
-LX_GDBPARSED(MOD_RO_AFTER_INIT)
+if IS_BUILTIN(CONFIG_MODULES):
+ LX_GDBPARSED(MOD_TEXT)
+ LX_GDBPARSED(MOD_DATA)
+ LX_GDBPARSED(MOD_RODATA)
+ LX_GDBPARSED(MOD_RO_AFTER_INIT)

/* linux/mount.h */
LX_VALUE(MNT_NOSUID)

Tested-by: Daniel Gomez <da.gomez@xxxxxxxxxxx>

> ---
> scripts/gdb/linux/constants.py.in | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/scripts/gdb/linux/constants.py.in b/scripts/gdb/linux/constants.py.in
> index 50a92c4e9984..866015547b38 100644
> --- a/scripts/gdb/linux/constants.py.in
> +++ b/scripts/gdb/linux/constants.py.in
> @@ -63,7 +63,8 @@ LX_GDBPARSED(IRQD_LEVEL)
> LX_GDBPARSED(IRQ_HIDDEN)
>
> /* linux/module.h */
> -LX_GDBPARSED(MOD_TEXT)
> +if IS_BUILTIN(CONFIG_MODULES):
> + LX_GDBPARSED(MOD_TEXT)
>
> /* linux/mount.h */
> LX_VALUE(MNT_NOSUID)
> --
> 2.40.1
>
>