Re: [PATCH] Fix interface autodetection in legacy IDE driver (trial #2)

[Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>]

On Tuesday, December 27, 2016 11:08:24 AM Bartlomiej Zolnierkiewicz wrote:
> 
> Hi,
> 
> On Monday, December 26, 2016 11:47:24 AM David Miller wrote:
> > From: Luiz Carlos Ramos <lramos.prof@yahoo.com.br>
> > Date: Tue, 11 Oct 2016 22:12:45 -0300
> > 
> > > This humble patch was sent one or two months before, and had no actions,
> > > except for a colleague reply which friendly pointed out some formatting
> > > problems (which were solved in a second message).
> > > 
> > > It relates to an old code, the legacy IDE driver, but the bug it
> > > addresses is real. The code, although rarely used, is
> > > still there to be compiled if one chooses to do so (like me).
> > > 
> > > Also, the fix has a very low risk of present collateral effects IMHO.
> > > It is already compiled and tested in some embedded machines.
> > > 
> > > So, again IMHO, it is worth be fixed.
> > > 
> > > This email is a second trial with it. I hope it can help the one or two
> > > guys out there which are still running the legacy IDE driver and
> > > haven't noticed the former email.
> > > 
> > > Best regards,
> > > 
> > > Signed-off-by: Luiz Carlos Ramos <lramos.prof@yahoo.com.br>
> > 
> > This bug was introduced by commit
> > 20df429dd6671804999493baf2952f82582869fa ("ide-generic: handle probing
> > of legacy io-ports v5") which seems poorly tested.
> 
> Please always cc: the original commit author.
> 
> > Applied and queued up for -stable, th anks.
> 
> For some reason I've never got the discussed patch from
> linux-ide ML though I now have found in the patchwork:
> 
> https://patchwork.ozlabs.org/patch/680975/
> 
> The patch is incorrect.  If you have PCI IDE devices (like in
> the case described in the situation being "fixed" by the patch)
> you should use the correct PCI IDE host driver for proper
> operation and not ide-generic host driver (the latter still can
> be used by using kernel parameters).

Moreover this patch introduces a regression.  In the situation
when there are no PCI IDE devices and the probing should be done
automatically (for the first two legacy IDE ports) it will be no
longer done.

Now back to the using correct PCI IDE host drivers - Luiz what
are the systems that you need this patch on?  Could you please
get 'lspci -nn' command output from them?

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics