Recent changes to tickets

Add parameter to control UNMAP granularity / provisioning slab for Windows initiators

Roman — Fri, 12 Dec 2025 12:09:42 -0000

Hello,
I’m using SCST with vdisk_fileio and Windows (iSCSI initiator).
Thin provisioning and UNMAP work, but Windows reports the following error during defrag /L (ReTrim):
“The slab size is too small”
Windows INBOX iSCSI initiator requires the storage to report provisioning slab ≥ 4096 bytes via VPD pages (LBPRZ/LBPPBE/OPTIMAL UNMAP GRANULARITY).
Currently, SCST only exposes lb_per_pb_exp, which affects LBPPBE, but there is no parameter to set the provisioning slab (also UNMAP granularity).
As a result, Windows sees:
Logical sector: 512
Physical sector: 4096
But slab = 512 (too small → ReTrim fails)
Could you please add a configurable parameter for:
Provisioning slab size (e.g. unmap_granularity or slab_size)
Optionally, UNMAP alignment
These values must be exposed via the appropriate VPD pages so the Windows initiator will accept the device for ReTrim/Optimize.
This would greatly improve Windows compatibility for thin-file-backed LUNs (vdisk_fileio), especially in virtualized storage setups.

Active-Pasive cluster (Open ZFS) and Persistent Reservations

Adam Błaszczykowski — Tue, 27 Dec 2022 14:26:35 -0000

Hi,
I'm using scst 3.6 on kernel 5.15.74 and OpenZFS with Active-Pasive cluster

I have two nodes - active and passive. The active host has Pool from local and remote disks. The target is zvol (LUN0) - it is a block device, which is not a specific disk but consists of many devices.
Zvol is only visible on the active node as /dev/tank/zvol1
To test the operation of PR (persistent reservations) on a passive node, enter the device as below, but it ends with an error

echo "add_device blockio filename=/dev/tank/zvol1" >/sys/kernel/scst_tgt/handlers/vdisk_blockio/mgmt
-bash: echo: write error: No such file or directory

Is it possible to indicate the device differently on the passive node?

Regards
Adam

Unable to build on RHEL 9.1

Mike Khosraviani — Tue, 29 Nov 2022 00:04:15 -0000

Compilation is broken for OS RHEL 9.1 kernel 5.14.0-162.6.1.el9_1.x86_64:

[root@scspa2671671002 ontap-mediator-1.6.0]# uname -a
Linux scspa2671671002.rtp.openenglab.netapp.com 5.14.0-162.6.1.el9_1.x86_64 #1 SMP PREEMPT_DYNAMIC Fri Sep 30 07:36:03 EDT 2022 x86_64 x86_64 x86_64 GNU/Linux
[root@scspa2671671002 ontap-mediator-1.6.0]#

[root@scspa2671671002 ontap-mediator-1.6.0]# cat /etc/redhat-release
Red Hat Enterprise Linux release 9.1 (Plow)
[root@scspa2671671002 ontap-mediator-1.6.0]# cat /etc/os-release
NAME="Red Hat Enterprise Linux"
VERSION="9.1 (Plow)"
ID="rhel"
ID_LIKE="fedora"
VERSION_ID="9.1"
PLATFORM_ID="platform:el9"
PRETTY_NAME="Red Hat Enterprise Linux 9.1 (Plow)"
ANSI_COLOR="0;31"
LOGO="fedora-logo-icon"
CPE_NAME="cpe:/o:redhat:enterprise_linux:9::baseos"
HOME_URL="https://www.redhat.com/"
DOCUMENTATION_URL="https://access.redhat.com/documentation/red_hat_enterprise_linux/9/"
BUG_REPORT_URL="https://bugzilla.redhat.com/"

REDHAT_BUGZILLA_PRODUCT="Red Hat Enterprise Linux 9"
REDHAT_BUGZILLA_PRODUCT_VERSION=9.1
REDHAT_SUPPORT_PRODUCT="Red Hat Enterprise Linux"
REDHAT_SUPPORT_PRODUCT_VERSION="9.1"
[root@scspa2671671002 ontap-mediator-1.6.0]#

Compilation error below:

[2022-11-28 18:42:05] In file included from /tmp/ontap_mediator.UFnM45/ontap-mediator-1.6.0/ontap-mediator-1.6.0/dist/scst/scst-3.7.0-pre/scst/src/../include/scst.h:54,
[2022-11-28 18:42:05] from /tmp/ontap_mediator.UFnM45/ontap-mediator-1.6.0/ontap-mediator-1.6.0/dist/scst/scst-3.7.0-pre/scst/src/scst_copy_mgr.c:17:
[2022-11-28 18:42:05] ./include/scsi/scsi_cmnd.h:179:6: note: previous declaration of 'scsi_done' with type 'void(struct scsi_cmnd )'
[2022-11-28 18:42:05] 179 | void scsi_done(struct scsi_cmnd cmd);
[2022-11-28 18:42:05] | ^~~~~~~~~

Unable to build on RHEL 8.6

Mike Khosraviani — Fri, 19 Aug 2022 20:46:29 -0000

I tried building scst-trunk (svn co as of 8/18/2022) on an RHEL 8.6 system and got the following error:

scst_vdisk.c:489:9: error: too many arguments to function ‘blkdev_issue_flush’

[2022-08-19 13:38:06] make[3]: Entering directory '/usr/src/kernels/4.18.0-372.9.1.el8.x86_64'
[2022-08-19 13:38:08] CC [M] /tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst/src/dev_handlers/scst_cdrom.o
[2022-08-19 13:38:09] CC [M] /tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst/src/dev_handlers/scst_changer.o
[2022-08-19 13:38:10] CC [M] /tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst/src/dev_handlers/scst_disk.o
[2022-08-19 13:38:11] CC [M] /tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst/src/dev_handlers/scst_modisk.o
[2022-08-19 13:38:13] CC [M] /tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst/src/dev_handlers/scst_tape.o
[2022-08-19 13:38:14] CC [M] /tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst/src/dev_handlers/scst_vdisk.o
[2022-08-19 13:38:15] /tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst/src/dev_handlers/scst_vdisk.c: In function ‘vdisk_blockio_flush’:
[2022-08-19 13:38:15] /tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst/src/dev_handlers/scst_vdisk.c:489:9: error: too many arguments to function ‘blkdev_issue_flush’
[2022-08-19 13:38:15] res = blkdev_issue_flush(bdev, gfp_mask);
[2022-08-19 13:38:15] ^~~~~~~~~~~~~~~~~~
[2022-08-19 13:38:15] In file included from ./include/linux/blk-cgroup.h:23,
[2022-08-19 13:38:15] from ./include/linux/writeback.h:15,
[2022-08-19 13:38:15] from /tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst/src/dev_handlers/scst_vdisk.c:40:
[2022-08-19 13:38:15] ./include/linux/blkdev.h:1288:5: note: declared here
[2022-08-19 13:38:15] int blkdev_issue_flush(struct block_device bdev);
[2022-08-19 13:38:15] ^~~~~~~~~~~~~~~~~~
[2022-08-19 13:38:15] make[4]: [scripts/Makefile.build:322: /tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst/src/dev_handlers/scst_vdisk.o] Error 1
[2022-08-19 13:38:15] make[3]: [Makefile:1577: module/tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst/src/dev_handlers] Error 2
[2022-08-19 13:38:15] make[3]: Leaving directory '/usr/src/kernels/4.18.0-372.9.1.el8.x86_64'
[2022-08-19 13:38:15] make[2]: [Makefile:76: all] Error 2
[2022-08-19 13:38:15] make[2]: Leaving directory '/tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst/src'
[2022-08-19 13:38:15] make[1]: [Makefile:39: install] Error 2
[2022-08-19 13:38:15] make[1]: Leaving directory '/tmp/ontap_mediator.PC0Imv/ontap-mediator-1.5.0/ontap-mediator-1.5.0/dist/scst/scst-3.7.0-pre/scst'
[2022-08-19 13:38:15] make: ** [Makefile:158: scst_install] Error 2
[root@scs000088802-1 ~]#

OS Information:

[root@scs000088802-1 ~]# cat /etc/redhat-release
Red Hat Enterprise Linux release 8.6 (Ootpa)
[root@scs000088802-1 ~]# cat /etc/os-release
NAME="Red Hat Enterprise Linux"
VERSION="8.6 (Ootpa)"
ID="rhel"
ID_LIKE="fedora"
VERSION_ID="8.6"
PLATFORM_ID="platform:el8"
PRETTY_NAME="Red Hat Enterprise Linux 8.6 (Ootpa)"
ANSI_COLOR="0;31"
CPE_NAME="cpe:/o:redhat:enterprise_linux:8::baseos"
HOME_URL="https://www.redhat.com/"
DOCUMENTATION_URL="https://access.redhat.com/documentation/red_hat_enterprise_linux/8/"
BUG_REPORT_URL="https://bugzilla.redhat.com/"

REDHAT_BUGZILLA_PRODUCT="Red Hat Enterprise Linux 8"
REDHAT_BUGZILLA_PRODUCT_VERSION=8.6
REDHAT_SUPPORT_PRODUCT="Red Hat Enterprise Linux"
REDHAT_SUPPORT_PRODUCT_VERSION="8.6"
[root@scs000088802-1 ~]#

#59 Unable to compile ISCSI module on 5.15 kernel with ISER

Gleb Chesnokov — Fri, 29 Jul 2022 10:47:27 -0000

Hi,

Thank you for the report. I will take a look at it soon.

Thanks,
Gleb

Unable to compile ISCSI module on 5.15 kernel with ISER

Yury Panchenko — Thu, 28 Jul 2022 13:20:56 -0000

Hello SCST team,
I have server on Ubuntu 20.04. The system uses HWE kernel 5.15
The server has few mellanox-6 network cards with MOFED 5.6 drivers

When I try to build iscsi module it always failed with infiband errors
Could you fix that?
Thank you.

make[2]: Entering directory '/usr/src/linux-headers-5.15.0-41-generic'
CC [M] /root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.o
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c: In function ‘isert_post_recv’:
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:90:50: error: passing argument 3 of ‘ib_post_recv’ from incompatible pointer type [-Werror=incompatible-pointer-types]
90 | err = ib_post_recv(isert_conn->qp, first_ib_wr, &bad_wr);
| ^~~~~~~
| |
| struct ib_recv_wr
In file included from /usr/src/ofa_kernel/default/include/rdma/ib_mad.h:15,
from /usr/src/ofa_kernel/default/include/rdma/ib_cm.h:13,
from /root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:44:
/usr/src/ofa_kernel/default/include/rdma/ib_verbs.h:3941:37: note: expected ‘const struct ib_recv_wr ’ but argument is of type ‘struct ib_recv_wr ’
3941 | const struct ib_recv_wr bad_recv_wr)
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c: In function ‘isert_post_send’:
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:137:50: error: passing argument 3 of ‘ib_post_send’ from incompatible pointer type [-Werror=incompatible-pointer-types]
137 | err = ib_post_send(isert_conn->qp, first_ib_wr, &bad_wr);
| ^~~~~~~
| |
| struct ib_send_wr
In file included from /usr/src/ofa_kernel/default/include/rdma/ib_mad.h:15,
from /usr/src/ofa_kernel/default/include/rdma/ib_cm.h:13,
from /root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:44:
/usr/src/ofa_kernel/default/include/rdma/ib_verbs.h:3924:37: note: expected ‘const struct ib_send_wr ’ but argument is of type ‘struct ib_send_wr ’
3924 | const struct ib_send_wr bad_send_wr)
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c: In function ‘isert_post_drain_sq’:
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:167:33: error: passing argument 3 of ‘ib_post_send’ from incompatible pointer type [-Werror=incompatible-pointer-types]
167 | &drain_wr_sq->send_wr.wr, &bad_wr);
| ^~~~~~~
| |
| struct ib_send_wr
In file included from /usr/src/ofa_kernel/default/include/rdma/ib_mad.h:15,
from /usr/src/ofa_kernel/default/include/rdma/ib_cm.h:13,
from /root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:44:
/usr/src/ofa_kernel/default/include/rdma/ib_verbs.h:3924:37: note: expected ‘const struct ib_send_wr ’ but argument is of type ‘struct ib_send_wr ’
3924 | const struct ib_send_wr bad_send_wr)
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c: In function ‘isert_post_drain_rq’:
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:192:30: error: passing argument 3 of ‘ib_post_recv’ from incompatible pointer type [-Werror=incompatible-pointer-types]
192 | &drain_wr_rq->recv_wr, &bad_wr);
| ^~~~~~~
| |
| struct ib_recv_wr
In file included from /usr/src/ofa_kernel/default/include/rdma/ib_mad.h:15,
from /usr/src/ofa_kernel/default/include/rdma/ib_cm.h:13,
from /root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:44:
/usr/src/ofa_kernel/default/include/rdma/ib_verbs.h:3941:37: note: expected ‘const struct ib_recv_wr ’ but argument is of type ‘struct ib_recv_wr ’
3941 | const struct ib_recv_wr bad_recv_wr)
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c: In function ‘isert_device_create’:
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:998:8: error: macro "ib_create_cq" passed 6 arguments, but takes just 5
998 | i); / completion vector /
| ^
In file included from /usr/src/ofa_kernel/default/include/rdma/ib_mad.h:15,
from /usr/src/ofa_kernel/default/include/rdma/ib_cm.h:13,
from /root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:44:
/usr/src/ofa_kernel/default/include/rdma/ib_verbs.h:4009: note: macro "ib_create_cq" defined here
4009 | #define ib_create_cq(device, cmp_hndlr, evt_hndlr, cq_ctxt, cq_attr) \
|
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:993:8: error: ‘ib_create_cq’ undeclared (first use in this function); did you mean ‘ib_create_wq’?
993 | cq = ib_create_cq(ib_dev,
| ^~~~~~~~~~~~
| ib_create_wq
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:993:8: note: each undeclared identifier is reported only once for each function it appears in
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c: In function ‘isert_conn_create’:
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:1233:47: error: ‘struct ib_device_attr’ has no member named ‘max_sge’; did you mean ‘max_cqe’?
1233 | isert_conn->max_sge = isert_dev->device_attr.max_sge - 3;
| ^~~~~~~
| max_cqe
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c: In function ‘isert_cm_conn_req_handler’:
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:1482:2: error: too few arguments to function ‘rdma_reject’
1482 | rdma_reject(cm_id, NULL, 0
| ^~~~~~~~~~~
In file included from /usr/src/ofa_kernel/default/include/rdma/ib_cm.h:15,
from /root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:44:
/usr/src/ofa_kernel/default/include/rdma/rdma_cm.h:272:5: note: declared here
272 | int rdma_reject(struct rdma_cm_id id, const void private_data,
| ^~~~~~~~~~~
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c: In function ‘isert_setup_id’:
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:1731:20: error: macro "rdma_create_id" requires 5 arguments, but only 4 given
1731 | IB_QPT_RC);
| ^
In file included from /usr/src/ofa_kernel/default/include/rdma/ib_cm.h:15,
from /root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:44:
/usr/src/ofa_kernel/default/include/rdma/rdma_cm.h:139: note: macro "rdma_create_id" defined here
139 | #define rdma_create_id(net, event_handler, context, ps, qp_type) \
|
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:1730:7: error: ‘rdma_create_id’ undeclared (first use in this function); did you mean ‘rdma_create_qp’?
1730 | id = rdma_create_id(isert_cm_evt_handler, portal, RDMA_PS_TCP,
| ^~~~~~~~~~~~~~
| rdma_create_qp
At top level:
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:1617:12: warning: ‘isert_cm_evt_handler’ defined but not used [-Wunused-function]
1617 | static int isert_cm_evt_handler(struct rdma_cm_id cm_id,
| ^~~~~~~~~~~~~~~~~~~~
/root/scst/scst/iscsi-scst/kernel/isert-scst/iser_rdma.c:770:13: warning: ‘isert_cq_comp_handler’ defined but not used [-Wunused-function]
770 | static void isert_cq_comp_handler(struct ib_cq cq, void *context)
| ^~~~~~~~~~~~~~~~~~~~~

#31 RFE: Hash IncomingUser in SCST.conf

Mike Khosraviani — Thu, 28 Apr 2022 14:07:58 -0000

Can anybody pick this up and submit a patch for it, please?

Getting "authentication bypass" when running Codenomicon/Defensics

Mike Khosraviani — Thu, 14 Apr 2022 17:19:29 -0000

I am getting "authentication bypass" errors when running Codenomicon/Defensics on v3.6.0 of SCST. The following Codenomicon test cases are producing this error: 57892,57896,57899,57946,58838,58840,58841

NOTES:
- The test cases show as "PASS" in "statistics"
- They all show "authentication bypass" failures in "Safeguard"
- Codenomicon is the old name for Defensics - a security checker tool by Synopsis

Attached are some files to show the problem/issue.
Please, advise if this is a real issue; and if so, how can it be resolved?

#57 Download link still downloads v3.5.0 instead of v3.6.0

Mike Khosraviani — Thu, 20 Jan 2022 14:05:49 -0000

Gleb, thanks for responding (in a private email) regarding this issue. Here is the gist of our discussion, and Gleb's response:

Hi Mike,

Do you know if an official tar.bz2 is going to come to Source Forge, anytime soon, please?

This download link: https://sourceforge.net/projects/scst/ still
downloads scst-3.5.0.tar.bz

The SCST has moved to the GitHub since December 2021.
You can find the latest release there https://github.com/SCST-project/scst/releases/tag/v3.6

You can also find the actual information about the SCST releases on the official site http://scst.sourceforge.net/downloads.html (Download released versions button)

Thanks,

Gleb.

I will create my own tar.bz2 to use since we require it in that format. Thanks so much for your prompt respond and you may consider this ticket resolved.

Download link still downloads v3.5.0 instead of v3.6.0

Mike Khosraviani — Wed, 19 Jan 2022 20:33:13 -0000

The official released link: https://sourceforge.net/projects/scst/

still point to scst-3.5.0.tar.bz2 Is there an equivalent for 3.6.0, please?