[Users] kernel: scsi host8: ib_srp: SRP_LOGIN_REJ: requested max_it_iu_len too large

[Bart Van Assche]

On 2020-01-16 14:16, Tom Robinson wrote:
> On the Arch system:
> 
> # uname -a
> Linux daytona.motec.com.au 5.4.11-arch1-1 #1 SMP PREEMPT Sun, 12 Jan
> 2020 12:15:27 +0000 x86_64 GNU/Linux
> 
> The /etc/srp_daemon.conf holds only comments. This is consistent with
> the original CentOS system.
> 
> Originally I had no configuration for the ib_srp module. I adjusted
> cmd_sg_entries=128 after reading this:
> https://www.spinics.net/lists/linux-rdma/msg29124.html. That change
> didn't help resolve this issue. The module options are currently set
> as follows:
> 
> # cat /etc/modprobe.d/ib_srp.conf
> options ib_srp cmd_sg_entries=128
> 
> 
> The target system is OmniOS running COMSTAR. This configuration has
> been working with CentOS 7 for a few years.

Hi Tom,

That's much more information than I need :-) Anyway, can you try to set
the use_imm_data ib_srp kernel module parameter to 'N'? Immediate data
is a relatively new feature of the SRP initiator driver. If it is
enabled the max_it_iu_len value in the SRP login request is larger.
Disabling immediate data support causes the SRP initiator to use the old
and smaller max_it_iu_len value during login.

I will look into modifying the SRP initiator such that it automatically
retries logging in without immediate data support if logging in with
immediate data enabled fails.

Bart.