Meelis Roos reports a crash in esp_free_lun_tag() in the presense
of a disk which has died.
The issue is that when we issue an autosense command, we do so by
hijacking the original command that caused the check-condition.
When we do so we clear out the ent->tag[] array when we issue it via
find_and_prep_issuable_command(). This is so that the autosense
command is forced to be issued non-tagged.
That is problematic, because it is the value of ent->tag[] which
determines whether we issued the original scsi command as tagged
vs. non-tagged (see esp_alloc_lun_tag()).
And that, in turn, is what trips up the sanity checks in
esp_free_lun_tag(). That function needs the original ->tag[] values
in order to free up the tag slot properly.
Fix this by remembering the original command's tag values, and
having esp_alloc_lun_tag() and esp_free_lun_tag() use them.
Reported-by: Meelis Roos <mroos@linux.ee>
Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: David S. Miller <davem@davemloft.net>
21af8107f2