Re: [SCSI] fix media change events for polled devices

[Kay Sievers <kay.sievers@vrfy.org>]

On Fri, 2008-03-21 at 13:12 -0400, Jeff Garzik wrote:
> Linux Kernel Mailing List wrote:
> >     [SCSI] fix media change events for polled devices
> >     
> >     Commit:
> >       a341cd0f (SCSI: add asynchronous event notification API)
> >     breaks:
> >       285e9670 (sr,sd: send media state change modification events)
> >     by introducing an event filter, which is removed here, to make
> >     events, we are depending on, happen again.
> 
> 
> By simply reading the code history, it is trivial to verify that this 
> description is false:
> 
> Commit 285e9670 depends on a341cd0f, so by definition it is 285e9670 -- 
> or rather the incomplete update of your original patch that resulted in 
> 285e9670 -- that is broken.

It worked fine with Kristen's patches, and that's where it is coming
from from.

> Since commit 285e9670 is broken, you fixed the wrong thing.
> 
> Furthermore, you broke a userspace interface that was introduced by 
> a341cd0f, by removing the event filter controlled by userspace.

You mean the read-only sysfs attribute? :)

> Did anyone bother to read any code at all?
> 
> When 285e9670 was updated for the scsi_evt_* interface, it should have 
> initialized the supported_events mask.
> 
> And that is the fix -- initialize supported_events according to sr/sd's 
> needs, and revert this change (4d1566ed2100d074ccc654e5cf2e44cdea3a01d0) 
> as obviously broken.

You mean adding a new flag? As every device will "support" these events.

Thanks,
Kay