Re: [PATCH] libata: Forcing PIO0 mode on reset must not freeze system

Tejun Heo
2008-02-11T10:49:40Z

Hello,

Holger Macht wrote:
>> In the above example, even the reset sequence itself can cause hang if
>> the hardware is implemented slightly differently. The reason why
>> set_piomode() locks up but reset sequence doesn't is simple dumb luck.
>
> Another thing, whether it's poor luck or not, it worked like this than at
> least 2.6.22. And it was _heavily_ tested. The above commit broke it
> between 2.6.24-rc1 and 2.6.24-rc2, which is at least a regression.

Yes, in a sense but the change is in the area where there's no defined
behavior, so I don't think it's a good idea to revert the change here.
Let's concentrate on finding the proper solution.

Thanks.

--
tejun