Can SSD wear leveling destroy data on a VeraCrypt partition?
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I found this alarming information in a post from a Micron employee about SSD wear leveling:
https://community.spiceworks.com/topic/451275-ssd-partitioning-is-reserve-space-necessary
"A key point is that, for most SSDs, and probably all of them from the big manufacturers, ANY UNUSED SPACE is used to manage garbage collection and wear leveling. It doesn't matter if it's unpartitioned space or if is is simply unused within the partition."
If you use VeraCrypt to encrypt an entire non-system partition, Windows Disk Management shows it as a RAW partition, and Windows will constantly offer to format it if you don't turn off the drive letter, so it must assume that it's unused.
My question is, is it possible that an SSD controller might regard a RAW partition as unused space and use it for wear leveling, thereby destroying the encrypted data it contains?
No.
The SSD keeps track of used space on its own, but has no knowledge of partitions or filesystems.
Blocks will only be marked as unused when the OS explicitly tells the SSD to TRIM the space occupied by deleted files, or when the SSD during a write decides to do wear-leveling and redirects the data to another block.
Even Microsoft is not that crazy to TRIM away space used by partitions it doesn't recognize.
Left over from times without TRIM, some SSDs recognize when a write results in a block containing all zeros, and will then mark that LBA address as unmapped and the previously occupied block as unused. But this will not result in data loss as a request for an unmapped block will always return zeros. On an encrypted volume, the chance that a block will be all zeros is extremely low, so this probably won't happen anyway.