Re: [RFC][PATCH 0/4] Make bpf_jit and kprobes work with CONFIG_MODULES=n

From: Luis Chamberlain <mcgrof@kernel.org>
To: Calvin Owens <jcalvinowens@gmail.com>, Song Liu <song@kernel.org>,
	Christophe Leroy <christophe.leroy@csgroup.eu>,
	Mike Rapoport <rppt@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Alexei Starovoitov <ast@kernel.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Andrii Nakryiko <andrii@kernel.org>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Naveen N Rao <naveen.n.rao@linux.ibm.com>,
	Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>,
	David S Miller <davem@davemloft.net>,
	Thomas Gleixner <tglx@linutronix.de>,
	bpf@vger.kernel.org, linux-modules@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [RFC][PATCH 0/4] Make bpf_jit and kprobes work with CONFIG_MODULES=n
Date: Wed, 6 Mar 2024 13:34:40 -0800	[thread overview]
Message-ID: <ZejhcP_r5QJZcS6j@bombadil.infradead.org> (raw)
In-Reply-To: <cover.1709676663.git.jcalvinowens@gmail.com>

On Wed, Mar 06, 2024 at 12:05:07PM -0800, Calvin Owens wrote:
> Hello all,
> 
> This patchset makes it possible to use bpftrace with kprobes on kernels
> built without loadable module support.

This is a step in the right direction for another reason: clearly the
module_alloc() is not about modules, and we have special reasons for it
now beyond modules. The effort to share a generalize a huge page for
these things is also another reason for some of this but that is more
long term.

I'm all for minor changes here so to avoid regressions but it seems a
rename is in order -- if we're going to all this might as well do it
now. And for that I'd just like to ask you paint the bikeshed with
Song Liu as he's been the one slowly making way to help us get there
with the "module: replace module_layout with module_memory",
and Mike Rapoport as he's had some follow up attempts [0]. As I see it,
the EXECMEM stuff would be what we use instead then. Mike kept the
module_alloc() and the execmem was just a wrapper but your move of the
arch stuff makes sense as well and I think would complement his series
nicely.

If you're gonna split code up to move to another place, it'd be nice
if you can add copyright headers as was done with the kernel/module.c
split into kernel/module/*.c

Can we start with some small basic stuff we can all agree on?

[0] https://lwn.net/Articles/944857/

  Luis