Re: [RFC][PATCH 2/3] exec: Simplify unshare_files

From: Oleg Nesterov
Date: Mon Sep 17 2018 - 12:23:47 EST


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.