Re: Unable to format or use floppies since 2.6.28

[Tejun Heo <tj@kernel.org>]

Hello,

On 12/17/2009 06:04 PM, Américo Wang wrote:
> On Sat, Dec 12, 2009 at 5:33 PM, ael <ael@none.none> wrote:
>> Mark Hounschell wrote:
>>>
>>> I have many boxes. They all do the same thing. Running different versions
>>> of SuSE, 10.3-11.2. Any kernel at or above 2.6.28 fails to fdformat a
>>> floppy. These same machines, using the same floppies and drives, running
>>> kernels older than 2.6.28 work just fine. I googled and found other such
>>> reports but no solution. I know better than to just assume it's a kernel bug
>>> but it sure looks like it could be so I'm inquiring about it here.

Hmmm... Strange.

>>> # fdformat /dev/fd0u1440
>>> Double-sided, 80 tracks, 18 sec/track. Total capacity 1440 kB.
>>> Formatting ... done
>>> Verifying ... Problem reading cylinder 1, expected 18432, read 2048
>>
>> Similar problems on debian testing: see
>> http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=548434
>>
>> However, fdformat is ok on Gentoo under 2.6.31 and also on Ubuntu
>> 2.6.32-rc6, so it seems it is not just the kernel version in any
>> simplistic way.

Double strange.

>> A git-bisect seems the obvious next step?
> 
> Wait...
> 
> There are only 13 changes related to floppy since 2.6.28, kick out 2 changes
> which just did some constifying, there are 11 only.
> 
> The most suspicious one should be commit 1011c1b9f2e from Tejun.
> 
> Mark, reverting that patch can help?

I don't think you can back that single patch out.  There were a lot of
cleanups in request handling after that.  How about trying 2.6.32
vanilla kernel?  Does it work?  How about copying fdformat from suse
to gentoo?

Thanks.

-- 
tejun