Re: IDE Floppy support for IOMEGA Zip Drive broken in 3.16 -> 3.17 transition

[Sergio Callegari <sergio.callegari@gmail.com>]

Hi Christoph,

thanks for your answer!

Any clue on how to help/speed up this? Was there any exchange with them when you 
first provided your patch back in 2014? Can it be restarted?

My feeling is that the issue fixed with 045065d8a300a37218c548e9aa7becd581c6a0e8 
was in fact the real paper over the bug. As distros start picking kernels with 
045065d8a300a37218c548e9aa7becd581c6a0e8 the issue is like to bite more and more.

And it is a subtle bug. In some cases takes ages before revealing, making one 
feel confident on a system that is in fact broken. And takes ages to bisect 
(took me almost 7 days).

Best,

Sergio



On 20/08/2015 10:08, Christoph Hellwig wrote:
> Hi Sergio,
>
> On Tue, Aug 18, 2015 at 09:44:28AM +0200, Sergio Callegari wrote:
>> Hi,
>>
>> I have bisected the issue down to
>>
>> [045065d8a300a37218c548e9aa7becd581c6a0e8] [SCSI] fix qemu boot hang problem
>>
>> Bisecting has been a painful job due to the fact that the bug may show only
>> many hours after the system boot.
>>
>> The commit above in fact is not the culprit, but a fix to an issue that was
>> hiding the real bug on my system.  See
>>
>> http://marc.info/?l=linux-kernel&m=143973820612978&w=2
>>
>> The real issue is with sata host lock and seems to be biting a few other
>> people as well
>>
>> https://bbs.archlinux.org/viewtopic.php?id=189324
>>
>> A patch fixing the issue was sent to the LKML back in Nov 2014 by Christoph
>> Hellwig (who is reading in CC)
>>
>> https://lkml.org/lkml/2014/11/20/581
>>
>> I have tested the patch and it works for me.
>>
>> What is expected to happen now?
> As mentioned in that thread we need more input from the libata people
> on what kind of race this is papering over.