Re: [PATCH 7/9] perf c2c: Fix hist entry and format list leaks in c2c_he_free()

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [Medium] perf_hpp__setup_output_field() and perf_hpp__append_sort_keys() append formats to the global perf_hpp_list instead of the provided local list, polluting global state and causing missing output columns.
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commit a4f0bc9a81bce084555c8dfe98ae2f6675da0ef8
Author: Arnaldo Carvalho de Melo <acme@redhat.com>

perf c2c: Fix hist entry and format list leaks in c2c_he_free()

This commit addresses leaks in c2c_he_free() by replacing
hists__delete_entries() with hists__delete_all_entries() to walk and free
all inner hist_entry objects across all rb_root trees. It also adds a call
to perf_hpp__reset_output_field() to unregister and free dynamically
allocated format entries on the hists->list.

> diff --git a/tools/perf/builtin-c2c.c b/tools/perf/builtin-c2c.c
> index eabb922ef295e..c9584dbedf77a 100644
> --- a/tools/perf/builtin-c2c.c
> +++ b/tools/perf/builtin-c2c.c
> @@ -184,7 +184,7 @@ static void c2c_he_free(void *he)
>  
>  	c2c_he = container_of(he, struct c2c_hist_entry, he);
>  	if (c2c_he->hists) {
> -		hists__delete_entries(&c2c_he->hists->hists);
> +		hists__delete_all_entries(&c2c_he->hists->hists);
>  		perf_hpp__reset_output_field(&c2c_he->hists->list);

[Severity: Medium]
This isn't a bug introduced by this patch, but does the setup for these local
hpp lists append formats to the global perf_hpp_list by mistake?

Looking at perf_hpp__setup_output_field() in tools/perf/ui/hist.c, it takes a
local list argument but uses the global wrapper perf_hpp__column_register(fmt)
instead of perf_hpp_list__column_register(list, fmt).

A similar issue appears in perf_hpp__append_sort_keys() in the same file,
which uses perf_hpp__register_sort_field(fmt) instead of
perf_hpp_list__register_sort_field(list, fmt).

Does this inject sort formats into the global list (polluting global state
during processing) while leaving the local list missing those columns and
breaking the output display for inner hists?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260615223249.36598-1-acme@kernel.org?part=7