linux-kernel - Re: [PATCH] kunit: added lockdep support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 10 Aug 2020 23:43:28 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     Uriel Guajardo <urielguajardojr@...il.com>
Cc:     brendanhiggins@...gle.com, mingo@...hat.com, will@...nel.org,
        urielguajardo@...gle.com, linux-kselftest@...r.kernel.org,
        kunit-dev@...glegroups.com, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] kunit: added lockdep support

On Mon, Aug 10, 2020 at 09:32:57PM +0000, Uriel Guajardo wrote:
> +static inline void kunit_check_locking_bugs(struct kunit *test,
> +					    unsigned long saved_preempt_count)
> +{
> +	preempt_count_set(saved_preempt_count);
> +#ifdef CONFIG_TRACE_IRQFLAGS
> +	if (softirq_count())
> +		current->softirqs_enabled = 0;
> +	else
> +		current->softirqs_enabled = 1;
> +#endif
> +#if IS_ENABLED(CONFIG_LOCKDEP)
> +	local_irq_disable();
> +	if (!debug_locks) {
> +		kunit_set_failure(test);
> +		lockdep_reset();
> +	}
> +	local_irq_enable();
> +#endif
> +}

Unless you can guarantee this runs before SMP brinup, that
lockdep_reset() is terminally broken.