Bug 219269 - v6.10.10 kernel fails to build when CONFIG_MODULES is disabled

Bug 219269 - v6.10.10 kernel fails to build when CONFIG_MODULES is disabled

[Thorsten Leemhuis]

Hi Greg! I noticed a bug report in bz:
https://bugzilla.kernel.org/show_bug.cgi?id=219269

> Fair enough, you get a compiler warning:
> 
> kernel/trace/trace_kprobe.c: In function ‘validate_probe_symbol’:
> kernel/trace/trace_kprobe.c:810:23: error: implicit declaration of function ‘find_module’; did you mean init_module’? [-Wimplicit-function-declaration]
>   810 |                 mod = find_module(modname);
>       |                       ^~~~~~~~~~~
>       |                       init_module
> kernel/trace/trace_kprobe.c:810:21: error: assignment to ‘struct module *’ from ‘int’ makes pointer from integer without a cast [-Wint-conversion]
>   810 |                 mod = find_module(modname);
>       |    
> 
> but there is no find_module symbol when CONFIG_MODULES is disabled.

I *very briefly* looked into this. I might be wrong, but looked a bit
like "tracing/kprobes: Add symbol counting check when module loads"
caused this and backporting b10545b6b86b7a ("tracing/kprobes: Fix build
error when find_module() is not available") [v6.11-rc1] would fix this
(which applies cleanly).

Shall I ask the reporter to confirm or is that already enough for you?

Ciao, Thorsten

Re: Bug 219269 - v6.10.10 kernel fails to build when CONFIG_MODULES is disabled

[Greg KH]

On Sat, Sep 14, 2024 at 07:02:26AM +0200, Thorsten Leemhuis wrote:
> Hi Greg! I noticed a bug report in bz:
> https://bugzilla.kernel.org/show_bug.cgi?id=219269
> 
> > Fair enough, you get a compiler warning:
> > 
> > kernel/trace/trace_kprobe.c: In function ‘validate_probe_symbol’:
> > kernel/trace/trace_kprobe.c:810:23: error: implicit declaration of function ‘find_module’; did you mean init_module’? [-Wimplicit-function-declaration]
> >   810 |                 mod = find_module(modname);
> >       |                       ^~~~~~~~~~~
> >       |                       init_module
> > kernel/trace/trace_kprobe.c:810:21: error: assignment to ‘struct module *’ from ‘int’ makes pointer from integer without a cast [-Wint-conversion]
> >   810 |                 mod = find_module(modname);
> >       |    
> > 
> > but there is no find_module symbol when CONFIG_MODULES is disabled.
> 
> I *very briefly* looked into this. I might be wrong, but looked a bit
> like "tracing/kprobes: Add symbol counting check when module loads"
> caused this and backporting b10545b6b86b7a ("tracing/kprobes: Fix build
> error when find_module() is not available") [v6.11-rc1] would fix this
> (which applies cleanly).
> 
> Shall I ask the reporter to confirm or is that already enough for you?

This is enough, now queued up, thanks.

greg k-h