Comment 1 for bug 1819504

There may be some confusion between the requested patch versus the expected functionality: The requested patch (https://patchwork.kernel.org/patch/10319623/) adds only a new **configfs** entry called "reset_netlink" but the returned test results (below) suggest that the tester was expecting a new **module parameter** called "reset_netlink". I also note that the discussion thread attached to the patchwork patch does mention the idea of doing it as a module parameter, but that idea is apparently rejected in favor of the configfs scheme implemented by the patch. Is it possible that the tester was originally working with an old version of the patch?

Also, the tester mentions expecting "block_netlink and reset_netlink" module params, but neither the patchwork patch nor mainline contains any reference to "block_netlink" at all.

My test kernel, with the reset_netlink patchwork patch (and many tcmu prerequisites from mainline) is available here:
  git source: https://git.launchpad.net/~kamalmostafa/ubuntu/+source/linux/+git/bionic/log/?h=tcmu-patch
  binary pkgs: https://kernel.ubuntu.com/~kamal/.tmp.4hthjg7s/

TEST RESULTS (via terrykrudd):
------------------------------
Unfortunately the build you gave us does not seem to include the kernel
patch to reset and unblock the tcmu netlink socket.

|dhana@gke-dhana-cluster-default-pool-596c314f-xn9f:~$ uname -a Linux
gke-dhana-cluster-default-pool-596c314f-xn9f 4.15.0-1028-gcp #29+tcmu0
SMP Fri Mar 8 20:33:39 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
dhana@gke-dhana-cluster-default-pool-596c314f-xn9f:~$ dpkg -l | grep
1028 ii linux-image-unsigned-4.15.0-1028-gcp 4.15.0-1028.29+tcmu0 amd64
Linux kernel image for version 4.15.0 on 64 bit x86 SMP ii
linux-modules-4.15.0-1028-gcp 4.15.0-1028.29+tcmu0 amd64 Linux kernel
extra modules for version 4.15.0 on 64 bit x86 SMP iU
linux-modules-extra-4.15.0-1028-gcp 4.15.0-1028.29+tcmu0 amd64 Linux
kernel extra modules for version 4.15.0 on 64 bit x86 SMP |

With the patch the /sys/module/target_core_user/parameters/ should
include block_netlink and reset_netlink entries such as:

|[root@demo06 crash]# ls -al /sys/module/target_core_user/parameters/
total 0 drwxr-xr-x 2 root root 0 Mar 11 16:47 . drwxr-xr-x 6 root root 0
Mar 8 11:37 .. -rw-r--r-- 1 root root 4096 Mar 8 14:31 block_netlink
-rw-r--r-- 1 root root 4096 Mar 11 16:47 global_max_data_area_mb
--w------- 1 root root 4096 Mar 8 14:31 reset_netlink |

But on the GKE instance with the patched kernel and modules we see:

|dhana@gke-dhana-cluster-default-pool-596c314f-xn9f:~$ ls -al
/sys/module/target_core_user/parameters/ total 0 drwxr-xr-x 2 root root
0 Mar 11 23:32 . drwxr-xr-x 6 root root 0 Mar 11 23:32 .. -rw-r--r-- 1
root root 4096 Mar 11 23:32 global_max_data_area_mb |

As you see the block_netlink and reset_netlink entries are not present.