hesela.devNVMe Write Uncorrectable
NVMe Write Uncorrectable marks a logical-block range invalid so subsequent reads report an Unrecovered Read Error until a write clears the state.
Invalidation changes the logical read contract; it does not demonstrate damaged flash or physical erasure. Clearing the invalid state with a later write is not recovery of the previous contents. [1]
The 16-bit NLB field is zero-based: 0 selects one block and 65535 selects 65536 blocks, subject to namespace bounds and command limits. Under NVM Command Set 1.3, interpret WUSL with NVMWUSV: a nonzero WUSL encodes a hard data-size limit when NVMWUSV=0 and a recommended maximum data size when NVMWUSV=1. Both fields zero means unsupported; WUSL=0 with NVMWUSV=1 instead reports no recommended maximum. [2]
An induced read error need not increase Media and Data Integrity Errors. Inclusion of Write Uncorrectable errors is optional. The counter alone therefore cannot confirm whether this command changed an LBA. [3]
Relations
- related
- NVMe Write Zeroes, NVMe Media and Data Integrity Errors, Logical block address, NVMe DULBE, Discard, NVMe sanitize
Limitations
- This state-changing command is unsuitable as a read-only health probe on live data. [1]
Citations
- libnvme v1.15: nvme_write_uncorrectable API contract
- NVM Command Set 1.3, sections 3.3.7 and 4.1.5.4. Copyright 2008-2026 NVM Express, Inc. All rights reserved.
- libnvme v1.15: nvme_smart_log.media_errors
Further reading
Sources & caveats
- Source review of NVM Command Set 1.3 and libnvme v1.15, not a device experiment; support rules are revision-scoped. No device command was executed.