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Date: Fri, 1 Jun 2018 17:56:12 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Christian Brauner <christian@brauner.io>
Cc: linux-kernel@vger.kernel.org, ebiederm@xmission.com,
        gregkh@linuxfoundation.org, mingo@kernel.org,
        james.morris@microsoft.com, keescook@chromium.org,
        peterz@infradead.org, sds@tycho.nsa.gov, viro@zeniv.linux.org.uk,
        akpm@linux-foundation.org
Subject: Re: [PATCH v2 03/17] signal: make may_ptrace_stop() return bool
Message-ID: <20180601155612.GB1058@redhat.com>
References: <20180601132239.4421-1-christian@brauner.io>
 <20180601132239.4421-4-christian@brauner.io>
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On 06/01, Christian Brauner wrote:
>
> may_ptrace_stop() already behaves like a boolean function. Let's actually
> declare it as such too.

OK. Then probably this patch should only make it return bool and do nothing else?

> -	if (unlikely(current->mm->core_state) &&
> -	    unlikely(current->mm == current->parent->mm))
> -		return 0;
> +	if (likely(!current->mm->core_state ||
> +		   current->mm != current->parent->mm))
> +		return false;

this is wrong.

Oleg.