Re: [PATCH 4.9 0/1] selinux: drop super_block backpointer from superblock_security_struct

[Greg KH <gregkh@linuxfoundation.org>]

On Thu, Aug 11, 2022 at 11:46:09AM +0200, Alexander Grund wrote:
> On 08.08.22 15:28, Greg KH wrote:
> > But, we only take patches that actually do something.  This one doesn't
> > do anything at all, and has no measurable performance or bugfix that I
> > can determine at all.
> 
> Isn't "doing less" also worth the patch?

Not if it doesn't actually fix something that a user sees.

> I mean this patch removes a superflous pointer of the superblock struct
> making the kernel use less memory.
> It also saves a code line and operation during init and removes the
> (somewhat hidden in syntax) superflous indirect access (and hence memory read)
> of a pointer already available (likely even in a register) during get/set_mnt_opts.
> 
> Of course the effect here is small but I think cleanups are always good to avoid
> a "death by a thousand cuts" scenario, i.e. that even small things help.

We do not take "cleanup patches" in stable trees without it being a
requirement for a real fix.  Please read the stable kernel rules
document again for what is actually allowed.

thanks,

greg k-h