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