Per the 82078 datasheet, if the end-of-track (EOT byte in
the FIFO) is more than the number of sectors per side, the
command is terminated unsuccessfully:
* 5.2.5 DATA TRANSFER TERMINATION
The 82078 supports terminal count explicitly through
the TC pin and implicitly through the underrun/over-
run and end-of-track (EOT) functions. For full sector
transfers, the EOT parameter can define the last
sector to be transferred in a single or multisector
transfer. If the last sector to be transferred is a par-
tial sector, the host can stop transferring the data in
mid-sector, and the 82078 will continue to complete
the sector as if a hardware TC was received. The
only difference between these implicit functions and
TC is that they return "abnormal termination" result
status. Such status indications can be ignored if they
were expected.
* 6.1.3 READ TRACK
This command terminates when the EOT specified
number of sectors have been read. If the 82078
does not find an I D Address Mark on the diskette
after the second· occurrence of a pulse on the
INDX# pin, then it sets the IC code in Status Regis-
ter 0 to "01" (Abnormal termination), sets the MA bit
in Status Register 1 to "1", and terminates the com-
mand.
* 6.1.6 VERIFY
Refer to Table 6-6 and Table 6-7 for information
concerning the values of MT and EC versus SC and
EOT value.
* Table 6·6. Result Phase Table
* Table 6-7. Verify Command Result Phase Table
Fix by aborting the transfer when EOT > # Sectors Per Side.
Cc: qemu-stable@nongnu.org
Cc: Hervé Poussineau <hpoussin@reactos.org>
Fixes: baca51faff ("floppy driver: disk geometry auto detect")
Reported-by: Alexander Bulekov <alxndr@bu.edu>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/339
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20211118115733.4038610-2-philmd@redhat.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
defac5e2fb