Re: [PATCH] unbreak all modern Seagate ATA pass-through for SMART

[Alan Stern <stern@rowland.harvard.edu>]

On Sun, Apr 25, 2021 at 02:15:36PM +0200, Rene Rebe wrote:
> From: Greg KH <gregkh@linuxfoundation.org>
> Subject: Re: [PATCH] unbreak all modern Seagate ATA pass-through for SMART
> Date: Sun, 25 Apr 2021 14:00:26 +0200
> 
> > > I would expect that more modern devices to work. Vendors usually
> > > linearly allocate their product ids for new devices, and we could
> > > allow list product ids higher than this Seven to unbreak more modern
> > > devices by default and limit the amount of device quirks needed?
> > 
> > Vendors do not allocate device ids that way at all, as there is no
> > requirement to do so.  I know of many vendors that seemingly use random
> > values from their product id space, so there is no guarantee that this
> > will work, sorry.
> 
> I did not say it is a requirement, just that they usually do speaking
> of just this Seagate case. What is wrong with using that to
> potentially significantly cut down the quirk list?

You didn't read commit 92335ad9e895, did you?  It lists a large number 
of Seagate devices that don't work with ATA pass-through, and three of 
them have product IDs that are larger than 0xab03.

Please check the facts before guessing about things that will cause 
problems for other people.

> > What is wrong with just allowing specific devices that you have tested
> > will work, to the list instead?  That's the safest way to handle this.
> 
> The problem is that out of the box it does not work for users, and
> normal users do not dive into the kernel code to find out and simply
> think their devices sucks. Even I for years thought the drive sucks,
> before I took a closer look. If you long term want more new devices in
> an allow list than the previous quirk list included (9 or 10 does not
> sound that many to me), ... whatever you prefer ,-) I would rather
> have 10 quirk disable list than potential many more white listed the
> next years to come. Maybe we shoudl simply restore the prevoius
> quirks.

That's a possibility, and in the future we may do it.  But probably not 
until the enable list grows to a comparable length.

Alan Stern