If this really is a problem which must be solved, why can’t it be solved in the same way in which RAM solves this problem, i.e. with ECC? Or with something like Forward Error Correction (support in dm-verity added in Linux 4.5).
That probably isn't the right granularity anymore.
A memory error should probably kick off a signal to the application. If the error isn't caught, then it should probably kill the process.
Memory errors should probably not cause a reboot unless they actually hit a kernel page.
http://www.intel.com/content/dam/www/public/us/en/documents/...
So even an application can recover from unrecoverable ECC errors.
But it's not feasible to solve this in applications, since there are many scenarios where such storage should simply be transparent.
Hardware support for Forward Error Correction would certainly be nice.
Software FEC support from the kernel wouldn't help applications that directly access persistent memory from userspace. Software FEC support in userspace would still need the kernel to pass through errors rather than treating them as fatal. (For instance, the kernel could send a signal when it detects an error, but provide a way for the application to explicitly read the data including any errors, so that the application can apply any error-correcting codes it has.)