Re: [PATCH v10 27/38] dyndbg-test: add do_bulk testpoint, rename do_prints to do_classes

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] test_dynamic_debug: unkillable process in do_bulk and do_classes
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commit 6245dc1853df17e050ea8032572222d30c017fd7
Author: Jim Cromie <jim.cromie@gmail.com>

dyndbg-test: add do_bulk testpoint, rename do_prints to do_classes

This commit introduces a do_bulk testpoint and renames do_prints to
do_classes in the test_dynamic_debug module. These changes allow generating
high-volume workloads with a single sysfs write to better support testing of
dynamic debug features.

> diff --git a/lib/test_dynamic_debug.c b/lib/test_dynamic_debug.c
> index 01ce07001d4c7..560e23f14ac8f 100644
> --- a/lib/test_dynamic_debug.c
> +++ b/lib/test_dynamic_debug.c
[ ... ]
> -static void do_prints(void)
> +static void do_classes(unsigned int ct)
>  {
> -	pr_debug("do_prints:\n");
> -	do_cats();
> -	do_levels();
> +	/* maybe clamp this */
> +	pr_debug("do_classes %u times:\n", ct);
> +	for (; ct; ct--) {
> +		do_cats();
> +		do_levels();
> +		cond_resched();

[Severity: Medium]
Can this loop in do_classes() run indefinitely without checking for signals?

If a large integer (e.g., UINT_MAX) is written to the do_classes sysfs
parameter, the lack of fatal_signal_pending() or signal_pending() prevents
the test from being gracefully aborted via SIGKILL or SIGINT. This could
trap the process in kernel space and flood syslog/journald.

> +	}
> +}
> +
> +static void do_bulk(unsigned int ct)
> +{
> +	unsigned int i;
> +
> +	pr_debug("do_bulk %u times:\n", ct);
> +	for (i = 0; i < ct; i++) {
> +		pr_debug("bulk msg %u.0\n", i + 1);
> +		pr_debug("bulk msg %u.1\n", i + 1);
> +		pr_debug("bulk msg %u.2\n", i + 1);
> +		pr_debug("bulk msg %u.3\n", i + 1);
> +		pr_debug("bulk msg %u.4\n", i + 1);
> +		pr_debug("bulk msg %u.5\n", i + 1);
> +		pr_debug("bulk msg %u.6\n", i + 1);
> +		pr_debug("bulk msg %u.7\n", i + 1);
> +		pr_debug("bulk msg %u.8\n", i + 1);
> +		pr_debug("bulk msg %u.9\n", i + 1);
> +		cond_resched();

[Severity: Medium]
Similarly, does this loop in do_bulk() also need a signal check?

A process writing a large value to the do_bulk sysfs parameter could
become unkillable for an extended period, preventing process termination.

> +	}
>  }

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Sashiko AI review · https://sashiko.dev/#/patchset/20260916-dd-cmap-part2-clean-v10-0-af4cf4767707@gmail.com?part=27