linux-kernel - Re: [PATCH bpf-next v4 0/3] Allow mmap of /sys/kernel/btf/vmlinux

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <aC0OpCZCEziDXhwh@kodidev-ubuntu>
Date: Tue, 20 May 2025 16:22:12 -0700
From: Tony Ambardar <tony.ambardar@...il.com>
To: Alan Maguire <alan.maguire@...cle.com>
Cc: lmb@...valent.com, andrii@...nel.org, arnd@...db.de, ast@...nel.org,
	bpf@...r.kernel.org, daniel@...earbox.net, eddyz87@...il.com,
	haoluo@...gle.com, john.fastabend@...il.com, jolsa@...nel.org,
	kpsingh@...nel.org, linux-arch@...r.kernel.org,
	linux-kernel@...r.kernel.org, linux-kselftest@...r.kernel.org,
	martin.lau@...ux.dev, mykolal@...com, sdf@...ichev.me,
	shuah@...nel.org, song@...nel.org, yonghong.song@...ux.dev
Subject: Re: [PATCH bpf-next v4 0/3] Allow mmap of /sys/kernel/btf/vmlinux

On Thu, May 15, 2025 at 08:51:45AM +0100, Alan Maguire wrote:
> > I'd like to cut down the memory usage of parsing vmlinux BTF in ebpf-go.
> > With some upcoming changes the library is sitting at 5MiB for a parse.
> > Most of that memory is simply copying the BTF blob into user space.
> > By allowing vmlinux BTF to be mmapped read-only into user space I can
> > cut memory usage by about 75%.
> > 
> > Signed-off-by: Lorenz Bauer <lmb@...valent.com>
> 
> For the series,
> 
> Tested-by: Alan Maguire <alan.maguire@...cle.com>
> 
> Tested with 4k and 64k page size on aarch64; all worked perfectly. Thanks!

Hi Alan,

Thanks for taking a look at this. I've been following your related effort
to allow /sys/kernel/btf/vmlinux as a module in support of small systems
with kernel-size constraints, and wondered how this series might affect
that work? Such support would be well-received in the embedded space when
it happens, so am keen to understand.

Thanks,
Tony