Re: [Scst-devel] iscsi_scst: Unknown symbol backport_dependency_symbol

[Bart V. A. <bva...@ac...>]

On 07/17/18 09:28, Carsten Aulbert wrote:
> On 07/17/18 16:23, Bart Van Assche wrote:
>> MOFED is most useful for people who have a support contract with
>> Mellanox. If you don't have such a support contract I recommend to build
>> and run SCST against an upstream Linux kernel.
> 
> I see and I was not aware of that - and I'm not sure that buying cards
> with warranty by Mellanox already counts as a support contract.

I think a MOFED support contract has to be bought separately and that it 
is not included in the adapter warranty. I'm not sure that this is the 
right document but I think the following document explains the details: 
http://www.mellanox.com/pdf/products/M1Global_Brochure.pdf.

>> Is the kernel version
>> that you mentioned in your e-mail a vanilla kernel (from kernel.org) or
>> a Debian kernel (that means, a kernel that includes Debian patches)? In
>> the latter case, there may be an issue with one of the Debian IB
>> patches. Have you tried to install a vanilla kernel and to build and run
>> SCST against that kernel? Binary images of vanilla kernels are available
>> in the Debian testing and unstable repositories, e.g. package
>> linux-image-4.17.0-1.
> 
> I've tried the stock Debian kernel currently based on 4.9.110 but have
> not had a look at the applied patches yet.
> 
> Then, I'll go back to testing without MOFED for now, first with the
> stretch-backports kernel (4.16.x) and if that does not work, with a
> vanilla kernel.
> 
> Any suggestions which scst version I should try? Back to 3.2.x, 3.3.x
> from the SVN branch or "bleeding edge"?

The SCST trunk should work fine. The only feature in the trunk of which 
we know that it does not work reliably in combination with recent kernel 
versions is SCSI pass-through. This refers to the dev_* handlers, e.g. 
dev_disk. There have been significant changes in the Linux kernel v4.11 
block layer API and we need to review the integration of SCST and 
kernels >= 4.11. The target drivers in the trunk and the scst_vdisk and 
scst_fileio handlers should work fine however.

Bart.