linux-kernel - Re: [PATCH 0/5] bpf: Add user-space-publisher ringbuffer map type

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: <YvuzNaam90n4AJcm@maniforge.dhcp.thefacebook.com>
Date:   Tue, 16 Aug 2022 10:09:41 -0500
From:   David Vernet <void@...ifault.com>
To:     Hao Luo <haoluo@...gle.com>
Cc:     bpf@...r.kernel.org, ast@...nel.org, daniel@...earbox.net,
        andrii@...nel.org, john.fastabend@...il.com, martin.lau@...ux.dev,
        song@...nel.org, yhs@...com, kpsingh@...nel.org, sdf@...gle.com,
        jolsa@...nel.org, tj@...nel.org, joannelkoong@...il.com,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH 0/5] bpf: Add user-space-publisher ringbuffer map type

On Mon, Aug 15, 2022 at 02:13:13PM -0700, Hao Luo wrote:
> >
> > Iters allow userspace to kick the kernel, but IMO they're meant to enable
> > data extraction from the kernel, and dumping kernel data into user-space.
> 
> Not necessarily extracting data and dumping data. It could be used to
> do operations on a set of objects, the operation could be
> notification. Iterating and notifying are orthogonal IMHO.
> 
> > What I'm proposing is a more generalizable way of driving logic in the
> > kernel from user-space.
> > Does that make sense? Looking forward to hearing your thoughts.
> 
> Yes, sort of. I see the difference between iter and the proposed
> interface. But I am not clear about the motivation of a new APis for
> kicking callbacks from userspace. I guess maybe it will become clear,
> when you publish a concerte RFC of that interface and integrates with
> your userspace publisher.

Fair enough -- let me remove this from the cover letter in future
versions of the patch-set. To your point, there's probably little to be
gained in debating the merits of adding such APIs until there's a
concrete use-case.

Thanks,
David