Re: [PATCH] fix floppy for PAGE_SIZE != 4KB

[Jens Axboe <axboe@kernel.dk>]

On 11/14/25 6:41 AM, Rene Rebe wrote:
> For years I wondered why the floppy driver does not just work on
> sparc64, e.g:
> 
> root@SUNW_375_0066:# disktype /dev/fd0
> --- /dev/fd0
> disktype: Can't open /dev/fd0: No such device or address
> 
> [  525.341906] disktype: attempt to access beyond end of device
>                fd0: rw=0, sector=0, nr_sectors = 16 limit=8
> [  525.341991] floppy: error 10 while reading block 0
> 
> Turns out floppy.c __floppy_read_block_0 tries to read one page for
> the first test read to determine the disk size and thus fails if that
> is greater than 4k. Adjust minimum MAX_DISK_SIZE to PAGE_SIZE to fix
> floppy on sparc64 and likely all other PAGE_SIZE != 4KB configs.

16k seem like a lot to read from a floppy, no? Why isn't it just
reading a single 512b sector? Or just cap it at 4k rather than do
a full page, at least?

-- 
Jens Axboe