Re: [RFC on MODULE SUPPORT] hello, Rusty, Should we provide module information even if the kernel module compiled built-in with bzImage?

[Mathieu SEGAUD <mathieu.segaud@regala.cx>]

Vous m'avez dit récemment :

> hello, Rusty:
> I encountered a problem when modules compiled built-in with bzImage:
>
> open-iscsi is an iSCSI software, it has a userspace daemon(iscsid) and
> a userspace mani tool(iscsiadm) and a kernel module
> (scsi_transport_iscsi),
> recently the kernel module has been accepted into the official kernel
> release; since the module licensed with GPL, it could be compiled as
> built-in,
>
> but when I compiled the module within the bzImage, the problem appeared:
>
> tux ~ # iscsid -f
> iscsid: Missing or Invalid version from
> /sys/module/scsi_transport_iscsi/version. Make sure a up to date
> scsi_transport_iscsi module is loaded and a up todate version of
> iscsid is running. Exiting...
>
> this is just because iscsid hope there's an external module could be
> under /sys/module, and read the kernel module's version information,
> but if the module compiled built-in, all its module information
> discarded and it doesn't appeared under /sys/module/, that would break
> iscsid.
>
> Now the problem is:
>
> Should we provide module information under
> /sys/module/<module-name>/... even if the module compiled built-in
> with bzImage?
> Or just this module(scsi_transport_iscsi) should be marked with [M] only?
>
> if the former solution is preferred, I would be happy to work on
> MODULE_INFO-like macros improvements with CONFIG_MODULE undefined.

your userspace program is somewhat broken
the userspace should not expect to find the version number in
/sys/module, as this is used by the Linux kernel module subsystem. You
should provide the required information in another way such as a
/proc/ file (bad) or a /sys file (better, but no module stuff, this
has no business with it).

-- 
Mathieu