Drive's "Total NVM Capacity" is coming as 0B when using extended metadata (like 4k+16B/4k+64) under nvme-cli.

[sarabjotsoit]

Setup:

OS: Ubuntu 24.04
Kernel: 6.18.0-rc2-tls-102325+

Issue Description:

Total NVM Capacity is coming as 0B when using extended metadata using nvme-cli

From nvme-cli:

[mlx5/mlx5]kazan@perf-128-21:~$ sudo nvme list
Node                  Generic               SN                   Model                                    Namespace  Usage                      Format           FW Rev  
--------------------- --------------------- -------------------- ---------------------------------------- ---------- -------------------------- ---------------- --------
/dev/nvme2n1          /dev/ng2n1            S79JNG0Y400030       SAMSUNG MZ3LO1T9HCJR-00A07               0x1          4.10  kB /   0.00   B      4 KiB + 16 B   OPPA6B5Q

Capacity is coming up fine with smartctl, looks to be issue with nvme-cli

sudo smartctl -a /dev/nvme2
smartctl 7.4 2023-08-01 r5530 [x86_64-linux-6.18.0-rc2-tls-102325+] (local build)
Copyright (C) 2002-23, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF INFORMATION SECTION ===
Model Number:                       SAMSUNG MZ3LO1T9HCJR-00A07
Serial Number:                      S79JNG0Y400030
Firmware Version:                   OPPA6B5Q
PCI Vendor/Subsystem ID:            0x144d
IEEE OUI Identifier:                0x002538
Total NVM Capacity:                 1,920,383,410,176 [1.92 TB]
Unallocated NVM Capacity:           0
Controller ID:                      3
NVMe Version:                       1.4
Number of Namespaces:               128
Local Time is:                      Wed Dec 17 20:33:58 2025 PST
Firmware Updates (0x17):            3 Slots, Slot 1 R/O, no Reset required
Optional Admin Commands (0x007f):   Security Format Frmw_DL NS_Mngmt Self_Test Directvs MI_Snd/Rec
Optional NVM Commands (0x00df):     Comp Wr_Unc DS_Mngmt Wr_Zero Sav/Sel_Feat Timestmp Verify
Log Page Attributes (0x1e):         Cmd_Eff_Lg Ext_Get_Lg Telmtry_Lg Pers_Ev_Lg
Maximum Data Transfer Size:         8 Pages
Warning  Comp. Temp. Threshold:     77 Celsius
Critical Comp. Temp. Threshold:     85 Celsius
A few side effects:

Not able to create the FS on the drives as the reported size is zero.

[sarabjotsoit]

~$ sudo nvme list
Node                  Generic               SN                   Model                                    Namespace  Usage                      Format           FW Rev  
--------------------- --------------------- -------------------- ---------------------------------------- ---------- -------------------------- ---------------- --------
/dev/nvme2n1          /dev/ng2n1            S79JNG0Y400030       SAMSUNG MZ3LO1T9HCJR-00A07               0x1          4.10  kB /   0.00   B      4 KiB + 16 B   OPPA6B5Q

sudo smartctl -a /dev/nvme2
smartctl 7.4 2023-08-01 r5530 [x86_64-linux-6.18.0-rc2-tls-102325+] (local build)
Copyright (C) 2002-23, Bruce Allen, Christian Franke, www.smartmontools.org

=== START OF INFORMATION SECTION ===
Model Number:                       SAMSUNG MZ3LO1T9HCJR-00A07
Serial Number:                      S79JNG0Y400030
Firmware Version:                   OPPA6B5Q
PCI Vendor/Subsystem ID:            0x144d
IEEE OUI Identifier:                0x002538
Total NVM Capacity:                 1,920,383,410,176 [1.92 TB]
Unallocated NVM Capacity:           0
Controller ID:                      3
NVMe Version:                       1.4
Number of Namespaces:               128
Local Time is:                      Wed Dec 17 20:33:58 2025 PST
Firmware Updates (0x17):            3 Slots, Slot 1 R/O, no Reset required
Optional Admin Commands (0x007f):   Security Format Frmw_DL NS_Mngmt Self_Test Directvs MI_Snd/Rec
Optional NVM Commands (0x00df):     Comp Wr_Unc DS_Mngmt Wr_Zero Sav/Sel_Feat Timestmp Verify
Log Page Attributes (0x1e):         Cmd_Eff_Lg Ext_Get_Lg Telmtry_Lg Pers_Ev_Lg
Maximum Data Transfer Size:         8 Pages
Warning  Comp. Temp. Threshold:     77 Celsius
Critical Comp. Temp. Threshold:     85 Celsius

[keithbusch]

The "Total NVM Capacity" is a different value than the namespace capacity. The total comes from nvme id-ctrl /dev/nvme2, in a field called "tnvmcap".

What does nvme id-ns /dev/nvme2n1 show?

[sarabjotsoit]

Hi, @keithbusch

I have performed the test on another drive and am able to see the same issue. Please find the requested data

Total capacity is showing as 0B when using extended metadata using nvme-cli-2.16

# nvme list
Node                  Generic               SN                   Model                                    Namespace  Usage                      Format           FW Rev
--------------------- --------------------- -------------------- ---------------------------------------- ---------- -------------------------- ---------------- --------
/dev/nvme0n1          /dev/ng0n1            23470B800531         WUS5EA138ESP7E3                          0x1         70.85  GB /   0.00   B      4 KiB + 64 B   RC61000B
/dev/nvme0n2          /dev/ng0n2            23470B800531         WUS5EA138ESP7E3                          0x2         70.85  GB /   0.00   B      4 KiB + 64 B   RC61000B
/dev/nvme0n3          /dev/ng0n3            23470B800531         WUS5EA138ESP7E3                          0x3         70.85  GB /   0.00   B      4 KiB + 64 B   RC61000B
/dev/nvme0n4          /dev/ng0n4            23470B800531         WUS5EA138ESP7E3                          0x4         70.85  GB /   0.00   B      4 KiB + 64 B   RC61000B
/dev/nvme0n5          /dev/ng0n5            23470B800531         WUS5EA138ESP7E3                          0x5         70.85  GB /   0.00   B      4 KiB + 64 B   RC61000B
/dev/nvme0n6          /dev/ng0n6            23470B800531         WUS5EA138ESP7E3                          0x6        380.79  GB /   0.00   B      4 KiB + 64 B   RC61000B

Please find nvme id-ns and smartctl o/p

# nvme id-ns /dev/nvme0n1 -H
NVME Identify Namespace 1:
nsze    : 0x107ed42     Total size in logical blocks
ncap    : 0x107ed42     Maximum size in logical blocks
nuse    : 0x107ed42     Current size in logical blocks
nsfeat  : 0x12
  [7:7] : 0     NPRG, NPRA and NORS are Not Supported
  [6:6] : 0     Single Atomicity Mode applies to write operations
  [5:4] : 0x1   NPWG, NPWA, NPDG, NPDA, and NOWS are Supported
  [3:3] : 0     NGUID and EUI64 fields if non-zero, Reused
  [2:2] : 0     Deallocated or Unwritten Logical Block error Not Supported
  [1:1] : 0x1   Namespace uses NAWUN, NAWUPF, and NACWU
  [0:0] : 0     Thin Provisioning Not Supported
 
nlbaf   : 3
flbas   : 0x13
  [6:5] : 0     Most significant 2 bits of Current LBA Format Selected
  [4:4] : 0x1   Metadata Transferred at End of Data LBA
  [3:0] : 0x3   Least significant 4 bits of Current LBA Format Selected
 
mc      : 0x1
  [1:1] : 0     Metadata Pointer Not Supported
  [0:0] : 0x1   Metadata as Part of Extended Data LBA Supported
 
dpc     : 0x17
  [4:4] : 0x1   Protection Information Transferred as Last Bytes of Metadata Supported
  [3:3] : 0     Protection Information Transferred as First Bytes of Metadata Not Supported
  [2:2] : 0x1   Protection Information Type 3 Supported
  [1:1] : 0x1   Protection Information Type 2 Supported
  [0:0] : 0x1   Protection Information Type 1 Supported
 
dps     : 0
  [3:3] : 0     Protection Information is Transferred as Last Bytes of Metadata
  [2:0] : 0     Protection Information Disabled
 
nmic    : 0x1
  [1:1] : 0     Namespace is Not a Dispersed Namespace
  [0:0] : 0x1   Namespace Multipath Capable
 
rescap  : 0
  [7:7] : 0     Ignore Existing Key - Used as defined in revision 1.2.1 or earlier
  [6:6] : 0     Exclusive Access - All Registrants Not Supported
  [5:5] : 0     Write Exclusive - All Registrants Not Supported
  [4:4] : 0     Exclusive Access - Registrants Only Not Supported
  [3:3] : 0     Write Exclusive - Registrants Only Not Supported
  [2:2] : 0     Exclusive Access Not Supported
  [1:1] : 0     Write Exclusive Not Supported
  [0:0] : 0     Persist Through Power Loss Not Supported
 
fpi     : 0x80
  [7:7] : 0x1   Format Progress Indicator Supported
  [6:0] : 0     Format Progress Indicator (Remaining 0%)
 
dlfeat  : 9
  [4:4] : 0     Guard Field of Deallocated Logical Blocks is set to 0xFFFF
  [3:3] : 0x1   Deallocate Bit in the Write Zeroes Command is Supported
  [2:0] : 0x1   Bytes Read From a Deallocated Logical Block and its Metadata are 0x00
 
nawun   : 0
nawupf  : 0
nacwu   : 0
nabsn   : 0
nabo    : 0
nabspf  : 0
noiob   : 0
nvmcap  : 70,866,960,384
npwg    : 7
npwa    : 7
npdg    : 32767
npda    : 0
nows    : 0
mssrl   : 0
mcl     : 0
msrc    : 0
kpios   : 0
  [1:1] : 0     Key Per I/O Capability Not Supported
  [0:0] : 0     Key Per I/O Capability Disabled
 
nulbaf  : 0
kpiodaag: 0
anagrpid: 0
nsattr  : 0
  [0:0] : 0     Namespace Not Write Protected
 
nvmsetid: 0
endgid  : 0
nguid   : eb000000000000000014ee8401ce5000
eui64   : 0014ee8401ce5000
LBA Format  0 : Metadata Size: 0   bytes - Data Size: 512 bytes - Relative Performance: 0 Best
LBA Format  1 : Metadata Size: 8   bytes - Data Size: 512 bytes - Relative Performance: 0 Best
LBA Format  2 : Metadata Size: 0   bytes - Data Size: 4096 bytes - Relative Performance: 0 Best
LBA Format  3 : Metadata Size: 64  bytes - Data Size: 4096 bytes - Relative Performance: 0 Best (in use)

# smartctl -a /dev/nvme0n1
smartctl 7.4 2023-08-01 r5530 [x86_64-linux-6.18.0-base6.18-nvme6.19-rec-pad-param-121125+] (local build)
Copyright (C) 2002-23, Bruce Allen, Christian Franke, [www.smartmontools.org](http://www.smartmontools.org/)
 
=== START OF INFORMATION SECTION ===
Model Number:                       WUS5EA138ESP7E3
Serial Number:                      23470B800531
Firmware Version:                   RC61000B
PCI Vendor/Subsystem ID:            0x1b96
IEEE OUI Identifier:                0x0014ee
Total NVM Capacity:                 3,400,670,601,216 [3.40 TB]
Unallocated NVM Capacity:           2,665,157,451,776 [2.66 TB]
Controller ID:                      2
NVMe Version:                       1.4
Number of Namespaces:               128
Namespace 1 Size/Capacity:          70,847,307,776 [70.8 GB]
Namespace 1 Formatted LBA Size:     4096
Namespace 1 IEEE EUI-64:            0014ee 8401ce5000
Local Time is:                      Tue Feb 10 07:13:30 2026 UTC
Firmware Updates (0x19):            4 Slots, Slot 1 R/O, no Reset required
Optional Admin Commands (0x007f):   Security Format Frmw_DL NS_Mngmt Self_Test Directvs MI_Snd/Rec
Optional NVM Commands (0x0054):     DS_Mngmt Sav/Sel_Feat Timestmp
Log Page Attributes (0x5f):         S/H_per_NS Cmd_Eff_Lg Ext_Get_Lg Telmtry_Lg Pers_Ev_Lg Telmtry_Ar_4
Maximum Data Transfer Size:         8 Pages
Warning  Comp. Temp. Threshold:     77 Celsius
Critical Comp. Temp. Threshold:     82 Celsius
Namespace 1 Features (0x12):        NA_Fields NP_Fields
 
Supported Power States
St Op     Max   Active     Idle   RL RT WL WT  Ent_Lat  Ex_Lat
0 +    20.00W       -        -    0  0  0  0      400     400
1 +    16.00W       -        -    1  1  1  1      400     400
 
Supported LBA Sizes (NSID 0x1)
Id Fmt  Data  Metadt  Rel_Perf
0 -     512       0         0
1 -     512       8         0
2 -    4096       0         0
3 -    4096      64         0
 
=== START OF SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED
 
SMART/Health Information (NVMe Log 0x02)
Critical Warning:                   0x00
Temperature:                        38 Celsius
Available Spare:                    100%
Available Spare Threshold:          10%
Percentage Used:                    1%
Data Units Read:                    1,002,398,524 [513 TB]
Data Units Written:                 951,630,668 [487 TB]
Host Read Commands:                 17,299,583,806
Host Write Commands:                14,895,832,411
Controller Busy Time:               6,791
Power Cycles:                       25
Power On Hours:                     10,648
Unsafe Shutdowns:                   21
Media and Data Integrity Errors:    5
Error Information Log Entries:      6,286
Warning  Comp. Temperature Time:    0
Critical Comp. Temperature Time:    0
Temperature Sensor 1:               38 Celsius
Temperature Sensor 2:               36 Celsius
Temperature Sensor 3:               36 Celsius
Temperature Sensor 4:               42 Celsius
Temperature Sensor 5:               47 Celsius
Temperature Sensor 6:               44 Celsius
 
Error Information (NVMe Log 0x01, 16 of 256 entries)
Num   ErrCount  SQId   CmdId  Status  PELoc          LBA  NSID    VS  Message
  0       6286     0  0x17d4  0xc004  0x029            0     0     -  Invalid Field in Command
  1       6285     0  0xfcd4  0xc004  0x029            0     0     -  Invalid Field in Command
  2       6284     0  0xe2d4  0xc004  0x029            0     0     -  Invalid Field in Command
  3       6283     0  0xc8d4  0xc004  0x029            0     0     -  Invalid Field in Command
  4       6282     0  0xadd4  0xc004  0x029            0     0     -  Invalid Field in Command
  5       6281     0  0x92d4  0xc004  0x029            0     0     -  Invalid Field in Command
  6       6280     0  0x3cd4  0xc004  0x029            0     0     -  Invalid Field in Command
  7       6279     0  0x38d4  0xc004  0x029            0     0     -  Invalid Field in Command
  8       6278     0  0x34d4  0xc004  0x029            0     0     -  Invalid Field in Command
  9       6277     0  0x30d4  0xc004  0x029            0     0     -  Invalid Field in Command

[igaw]

Just to avoid misunderstanding on my side, we are talking about this here 380.79 GB / 0.00 B?

If so, nvme list is calculating the value with

	double nsze = nvme_ns_get_lba_count(n) * lba;

and

uint64_t nvme_ns_get_lba_count(nvme_ns_t n)
{
	return n->lba_count;
}

and lba_count is initialied in nvme_ns_init

[...]
		{ &size,          nvme_strtou64,  true, "size" },
		{ &ns->lba_size,  nvme_strtou32,  true, "queue/logical_block_size" },
[...]

	ns->lba_shift = GETSHIFT(ns->lba_size);
	/*
	 * size is in 512 bytes units and lba_count is in lba_size which are not
	 * necessarily the same.
	 */
	ns->lba_count = size >> (ns->lba_shift -  SECTOR_SHIFT);

Could you post the sysfs ouput size and queue/logical_block_size, just to make sure it's not a kernel issue:

root@nitrogen:~# cat /sys/devices/pci0000:00/0000:00:06.0/0000:01:00.0/nvme/nvme0/nvme0n1/size
1953525168
root@nitrogen:~# cat /sys/devices/pci0000:00/0000:00:06.0/0000:01:00.0/nvme/nvme0/nvme0n1/queue/logical_block_size
512

[keithbusch]

Oh, I missed the crucial point you're using the "extended" format. Linux fundamentally doesn't support it. We can't efficiently inline metadata with data in memory through the block stack. So yeah, the capacity is purposefully and artificially reported as zero in that case because you can't use it like a normal block device. nvme-cli's list command is just reporting what the kernel reports here rather than directly querying the device.

[sarabjotsoit]

HI, @igaw and @keithbusch

So, this looks like it's working as expected. Please confirm.

[igaw]

From my understanding yes, this is working correctly.

I'm closing the issue, feel free to reopen if there is still something unclear.