Ubuntu18.04: GPU total memory is reduced

I built a test kernel with commit 7acf50e4efa6. The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1792102

Can you test this kernel and see if it resolves this bug?

Note about installing test kernels:
• If the test kernel is prior to 4.15(Bionic) you need to install the linux-image and linux-image-extra .deb packages.
• If the test kernel is 4.15(Bionic) or newer, you need to install the linux-modules, linux-modules-extra and linux-image-unsigned .deb packages.

Thanks in advance!

------- Comment From <email address hidden> 2018-09-25 15:52 EDT-------
I haven't been able to verify this because I haven't been able to build the Nvidia GPU module against this kernel. If I try to use dkms to build it I get:
/bin/sh: 1: scripts/basic/fixdep: Exec format error
scripts/Makefile.build:332: recipe for target '/var/lib/dkms/nvidia/410.37/build/nvidia/nv-mempool.o' failed
make[2]: *** [/var/lib/dkms/nvidia/410.37/build/nvidia/nv-mempool.o] Error 2
make[2]: *** Waiting for unfinished jobs....

This has worked fine on the kernels I've built locally as well as the standard (or the -proposed kernel put out), but this kernel doesn't work. I also tried the test kernels from lp1790636 since that had the same build host and I get the same failure with them.

Any ideas? Any other way to validate it?

------- Comment From <email address hidden> 2018-09-26 13:11 EDT-------
I had to rebuild the utilities in scripts since those were the problem, they were x86 binaries.

The problem is fixed with this kernel:
user@deb3qwsp1:~$ cat /proc/version
Linux version 4.15.0-34-generic (jsalisbury@kathleen) (gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)) #38~lp1792102 SMP Wed Sep 12 19:55:58 UTC 2018
user@deb3qwsp1:~$ nvidia-smi |grep -A3 Memory
| Fan Temp Perf Pwr:Usage/Cap| Memory-Usage | GPU-Util Compute M. |
|===============================+======================+======================|
| 0 Tesla V100-SXM2... On | 00000004:04:00.0 Off | 0 |
| N/A 31C P0 34W / 300W | 0MiB / 16128MiB | 0% Default |

Bionic SRU request submitted:
https://lists.ubuntu.com/archives/kernel-team/2018-September/095678.html

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-bionic' to 'verification-done-bionic'. If the problem still exists, change the tag 'verification-needed-bionic' to 'verification-failed-bionic'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

I tested this against -proposed and it's fixed, thank you!

user@deb3qwsp1:~/gdrcopy$ cat /proc/version
Linux version 4.15.0-39-generic (buildd@bos02-ppc64el-016) (gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)) #42-Ubuntu SMP Tue Oct 23 15:41:45 UTC 2018
user@deb3qwsp1:~/gdrcopy$ nvidia-smi |grep -A3 Memory
| Fan Temp Perf Pwr:Usage/Cap| Memory-Usage | GPU-Util Compute M. |
|===============================+======================+======================|
| 0 Tesla V100-SXM2... On | 00000004:04:00.0 Off | 0 |
| N/A 31C P0 34W / 300W | 6MiB / 16128MiB | 0% Default |

This bug was fixed in the package linux - 4.15.0-39.42

---------------
linux (4.15.0-39.42) bionic; urgency=medium

  * linux: 4.15.0-39.42 -proposed tracker (LP: #1799411)

  * Linux: insufficient shootdown for paging-structure caches (LP: #1798897)
    - mm: move tlb_table_flush to tlb_flush_mmu_free
    - mm/tlb: Remove tlb_remove_table() non-concurrent condition
    - mm/tlb, x86/mm: Support invalidating TLB caches for RCU_TABLE_FREE
    - [Config] CONFIG_HAVE_RCU_TABLE_INVALIDATE=y

  * Ubuntu18.04: GPU total memory is reduced (LP: #1792102)
    - Revert "powerpc/powernv: Increase memory block size to 1GB on radix"

  * arm64: snapdragon: reduce boot noise (LP: #1797154)
    - [Config] arm64: snapdragon: DRM_MSM=m
    - [Config] arm64: snapdragon: SND*=m
    - [Config] arm64: snapdragon: disable ARM_SDE_INTERFACE
    - [Config] arm64: snapdragon: disable DRM_I2C_ADV7511_CEC
    - [Config] arm64: snapdragon: disable VIDEO_ADV7511, VIDEO_COBALT

  * [Bionic] CPPC bug fixes (LP: #1796949)
    - ACPI / CPPC: Update all pr_(debug/err) messages to log the susbspace id
    - cpufreq: CPPC: Don't set transition_latency
    - ACPI / CPPC: Fix invalid PCC channel status errors

  * regression in 'ip --family bridge neigh' since linux v4.12 (LP: #1796748)
    - rtnetlink: fix rtnl_fdb_dump() for ndmsg header

  * screen displays abnormally on the lenovo M715 with the AMD GPU (Radeon Vega
    8 Mobile, rev ca, 1002:15dd) (LP: #1796786)
    - drm/amd/display: Fix takover from VGA mode
    - drm/amd/display: early return if not in vga mode in disable_vga
    - drm/amd/display: Refine disable VGA

  * arm64: snapdragon: WARNING: CPU: 0 PID: 1 arch/arm64/kernel/setup.c:271
    reserve_memblock_reserved_regions (LP: #1797139)
    - SAUCE: arm64: Fix /proc/iomem for reserved but not memory regions

  * The front MIC can't work on the Lenovo M715 (LP: #1797292)
    - ALSA: hda/realtek - Fix the problem of the front MIC on the Lenovo M715

  * Keyboard backlight sysfs sometimes is missing on Dell laptops (LP: #1797304)
    - platform/x86: dell-smbios: Correct some style warnings
    - platform/x86: dell-smbios: Rename dell-smbios source to dell-smbios-base
    - platform/x86: dell-smbios: Link all dell-smbios-* modules together
    - [Config] CONFIG_DELL_SMBIOS_SMM=y, CONFIG_DELL_SMBIOS_WMI=y

  * rpi3b+: ethernet not working (LP: #1797406)
    - lan78xx: Don't reset the interface on open

  * 87cdf3148b11 was never backported to 4.15 (LP: #1795653)
    - xfrm: Verify MAC header exists before overwriting eth_hdr(skb)->h_proto

  * [Ubuntu18.04][Power9][DD2.2]package installation segfaults inside debian
    chroot env in P9 KVM guest with HTM enabled (kvm) (LP: #1792501)
    - KVM: PPC: Book3S HV: Fix guest r11 corruption with POWER9 TM workarounds

  * Provide mode where all vCPUs on a core must be the same VM (LP: #1792957)
    - KVM: PPC: Book3S HV: Provide mode where all vCPUs on a core must be the same
      VM

  * fscache: bad refcounting in fscache_op_complete leads to OOPS (LP: #1797314)
    - SAUCE: fscache: Fix race in decrementing refcount of op->npages

  * CVE-2018-9363
    - Bluetooth: hidp: buffer overflow in hidp_process_report

  * CVE-20...