[pve-devel] Please help: beginner trying to compile Proxmox kernel 4.15

[Fabian Grünbichler]

On Sat, Sep 22, 2018 at 12:19:02PM +0700, The Anh Tran wrote:
> Dear Teams,
> 
> I have Dell EMC ScaleIO (renamed to VxFlexOS) license.
> 
> ScaleIO has 3 components:
> SDS: server storage provider. This component could be installed on Proxmox
> ok.
> MDM: distributed storage metadata management. This is installed on a VM for
> HA & live-migration requirement.
> SDC: storage client consumer. This component could be installed on Proxmox
> ok.
> 
> I have posted a SR ticket on EMC site. They replied: "unable to support
> Proxmox distribution due to ... reasons".
> => have to solve this myself.
> 
> Sdc has a kernel module: scini.ko, which is a pre-compiled binary by EMC,
> for each support OS version (Redhat, Ubuntu, ...).
> scini.ko, which compiled on ubuntu xenial 16.04, has this module version
> magic string: "4.15.0-33-generic SMP mod_unload".
> Promox kernel 4.15.18-xy, while based on Ubuntu hwe kernel 4.15.18, has
> module magic string: "4.15.18-xy-pve SMP mod_unload modversions"

if you don't have a source for that module, (reliably) using it will not
be possible unless the vendor compiles it for you for every PVE kernel
update that changes the ABI.

> SDC boot script /etc/init.d/scini run this: "insmod /bin/emc/scini.ko"
> Magic string mismatch => kernel refuse to load
> I could change to force load: "insmod -f /bin/emc/scini.ko"
> But Proxmox compile flag inside debian/rules doesn't have
> "CONFIG_MODULE_FORCE_LOAD"
> 
> So, i could make scini.ko run on Proxmox by re-compile kernel, with some
> changes:
> _ add "-e CONFIG_MODULE_FORCE_LOAD \" in pve-kernel/debian/rules
> _ or modify pve-kernel/debian/rules: "-d CONFIG_MODVERSIONS \", and edit
> Makefile version string vars, from "4.15.18-xy-pve" to "4.15.0-xy-generic".
> 
> May I know the reason why you add "CONFIG_MODVERSIONS" or not enable
> "CONFIG_MODULE_FORCE_LOAD" flag?

even if we would enable force loading, there is absolutely no guarantee
that the module will actually work - (kernel) ABIs exist for a reason,
and our kernel and Ubuntu's are very close, but not ABI-compatible.