Re: [PATCH v2 04/10] perf symbol: Set binary/symtab type for split kallsyms

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] perf: Incorrect binary_type copied to split kallsyms DSOs
--

commit caef899ba7808ad89c1adfe535b155dac7c2ebd1
Author: Namhyung Kim <namhyung@kernel.org>

perf symbol: Set binary/symtab type for split kallsyms

When it creates new DSOs for split kallsyms, set the binary and symtab
type to KALLSYMS properly.

> diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> index cf099cbd29f26..fc6e4dff282bc 100644
> --- a/tools/perf/util/symbol.c
> +++ b/tools/perf/util/symbol.c
> @@ -1099,6 +1099,8 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta,
>  				return -1;
>  
>  			dso__set_kernel(ndso, dso__kernel(dso));
> +			dso__set_binary_type(ndso, dso__binary_type(dso));
> +			dso__set_symtab_type(ndso, dso__symtab_type(dso));

[Severity: Medium]
Are we copying an outdated binary_type into the new split DSOs here?

Looking at the execution flow, maps__split_kallsyms() is called via
dso__load_kallsyms() from within dso__load_kernel_sym():

dso__load_kernel_sym() {
	...
do_kallsyms:
	err = dso__load_kallsyms(dso, kallsyms_filename, map);
	...
	if (err > 0 && !dso__is_kcore(dso)) {
		...
		dso__set_binary_type(dso, DSO_BINARY_TYPE__KALLSYMS);
	...
}

Because dso__load_kallsyms() executes before dso__load_kernel_sym() updates
the parent dso's binary_type to DSO_BINARY_TYPE__KALLSYMS, the value returned
by dso__binary_type(dso) during the split operation may still be the old
stale value.

Could this prevent the split kallsyms DSOs from receiving the correct
binary and symtab types?

>  			dso__set_loaded(ndso);
>  
>  			curr_map = map__new2(pos->start, ndso);

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261006234315.920817-1-namhyung@kernel.org?part=4