Re: [RFC] seq_buf: Export symbols to external modules

From: Steven Rostedt
Date: Mon Apr 20 2020 - 15:20:48 EST


On Fri, 17 Apr 2020 14:47:48 +0530
Vaibhav Jain <vaibhav@xxxxxxxxxxxxx> wrote:

> Having these symbols exported to modules should simplify generating file
> content for pseudo file systems like sysfs or procfs. Many of the in
> kernel modules export atleast one such attribute file. Using seq_buf
> api provides a safe way to populate the read buffers for these attrs
> as these string buffers are PAGE_SIZE in length and a buggy module can
> easily cause an overflow.
>
> My specific use-case is exporting a set of nvdimm specific flags from
> papr_scm kernel module [1] via sysfs through a patch proposed at [2] and
> using seq_buf should considerably simply my code as suggested by Mpe
> at [3].
>
> [1] arch/powerpc/platforms/pseries/papr_scm.c
> [2] https://lore.kernel.org/linux-nvdimm/20200331143229.306718-2-vaibhav@xxxxxxxxxxxxx
> [3] https://lore.kernel.org/linux-nvdimm/878sjetcis.fsf@xxxxxxxxxxxxxxxxxx

This patch should be added to a patch series that needs it. Then I'll give
my ack to it. That way, there's a reason to export them.

-- Steve