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Date:   Mon, 17 Sep 2018 18:23:42 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     "Eric W. Biederman" <ebiederm@xmission.com>
Cc:     Jeff Layton <jlayton@kernel.org>, viro@zeniv.linux.org.uk,
        berrange@redhat.com, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [RFC][PATCH 2/3] exec: Simplify unshare_files
Message-ID: <20180917162342.GB25565@redhat.com>
References: <20180914105310.6454-1-jlayton@kernel.org>
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absolutely off-topic question,

On 09/16, Eric W. Biederman wrote:
>
> @@ -747,11 +746,9 @@ void do_coredump(const siginfo_t *siginfo)
>  	}
>
>  	/* get us an unshared descriptor table; almost always a no-op */
> -	retval = unshare_files(&displaced);
> +	retval = unshare_files();

I fail to understand why do_coredump() needs unshare_files(). Could someone
explain?

And "almost always a no-op" above is not true, this is never a no-op in mt case;
other (killed) threads sleep in exit_mm() which is called before exit_files().

Oleg.