Re: [PATCH] signal: Extend exec_id to 64bits

[Linus Torvalds]

On Wed, Apr 1, 2020 at 6:36 PM Jann Horn <jannh@xxxxxxxxxx> wrote:
>
> Since the read is already protected by the tasklist_lock, an
> alternative might be to let the execve path also take that lock to
> protect the sequence number update,

No.

tasklist_lock is aboue the hottest lock there is in all of the kernel.

We're not doing stupid things for theoretical issues.

Stop this crazy argument.

A comment - sure. 64-bit atomics or very expensive locks? Not a chance.

                   Linus