Re: [PATCH 1/3] mm: get_cmdline use arg_lock instead of mmap_sem

[Cyrill Gorcunov]

On Tue, Apr 30, 2019 at 12:09:57PM +0300, Kirill Tkhai wrote:
> 
> This looks OK for me.
> 
> But speaking about existing code it's a secret for me, why we ignore arg_lock
> in binfmt code, e.g. in load_elf_binary().

Well, strictly speaking we probably should but you know setup of
the @arg_start by kernel's elf loader doesn't cause any side
effects as far as I can tell (its been working this lockless
way for years, mmap_sem is taken later in the loader code).
Though for consistency sake we probably should set it up
under the spinlock.