I don't remember the details, but it may be, that status1 errors do not
raise INT_ERR (or do not always raise?). The idea is, first you check
INT_ERR. If command completed successfully and you received the data, you
may still need to check status1 for possible bit flips.
Some experimentation may be required, especially for the case of
correctable errors. After all, they should not prevent the command from
successful completion, yet action should be taken on them (at the very
least - log warning, just like with normal disks).
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