PCIe SSD disk temperature not reporting

There's no disk temperature reporting for a PCIe SSD.

relevant dmesg:
nvme0: mem 0xc4010000-0xc4013fff irq 48 at device 0.0 numa-domain 0 on pci14
nvd0: NVMe namespace
nvd0: 1907729MB (3907029168 512 byte sectors)

However, smartctl has no problem gathering temperature data:
[alexr@freenas ~]$ sudo smartctl -a /dev/nvme0
smartctl 6.6 2017-11-05 r4594 [FreeBSD 11.2-STABLE amd64] (local build)
Copyright (C) 2002-17, Bruce Allen, Christian Franke, www.smartmontools.org

=== START OF INFORMATION SECTION ===
Model Number: INTEL SSDPEDKE020T7
Serial Number: XXXXXXXXXXXXXXXXXX
Firmware Version: QDV10170
PCI Vendor/Subsystem ID: 0x8086
IEEE OUI Identifier: 0x5cd2e4
Total NVM Capacity: 2,000,398,934,016 [2.00 TB]
Unallocated NVM Capacity: 0
Controller ID: 0
Number of Namespaces: 1
Namespace 1 Size/Capacity: 2,000,398,934,016 [2.00 TB]
Namespace 1 Formatted LBA Size: 512
Namespace 1 IEEE EUI-64: 5cd2e4 6b72180100
Local Time is: Sun Dec 9 22:15:38 2018 PST
Firmware Updates (0x02): 1 Slot
Optional Admin Commands (0x0006): Format Frmw_DL
Optional NVM Commands (0x0006): Wr_Unc DS_Mngmt
Maximum Data Transfer Size: 32 Pages
Warning Comp. Temp. Threshold: 70 Celsius
Critical Comp. Temp. Threshold: 77 Celsius

Supported Power States
St Op Max Active Idle RL RT WL WT Ent_Lat Ex_Lat
0 + 25.00W - - 0 0 0 0 0 0

Supported LBA Sizes (NSID 0x1)
Id Fmt Data Metadt Rel_Perf
0 + 512 0 2
1 - 4096 0 0

=== START OF SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED

SMART/Health Information (NVMe Log 0x02, NSID 0xffffffff)
Critical Warning: 0x00
Temperature: 19 Celsius
Available Spare: 100%
Available Spare Threshold: 10%
Percentage Used: 0%
Data Units Read: 15,628,763 [8.00 TB]
Data Units Written: 16,739,935 [8.57 TB]
Host Read Commands: 61,056,688
Host Write Commands: 70,490,053
Controller Busy Time: 27
Power Cycles: 26
Power On Hours: 2,343
Unsafe Shutdowns: 11
Media and Data Integrity Errors: 0
Error Information Log Entries: 0
Warning Comp. Temperature Time: 0
Critical Comp. Temperature Time: 0

Error Information (NVMe Log 0x01, max 64 entries)
No Errors Logged