[Bug,200917] 4.18 regression: I/O error on external icybox disk enclosures

[Klaus Kusche <klaus.kusche@computerix.info>]

Hello,

On 03/10/2018 16:02, Alan Stern wrote:
> Well, what happens if you add only US_FL_BROKEN_FUA without
> US_FL_IGNORE_UAS?  Does it work?

Tried all four combinations with gentoo 4.18.12.
Just US_FL_IGNORE_UAS fails with the error message in the original bug report.

The other three combinations (both flags removed, both flags set,
just US_FL_BROKEN_FUA set) work, at least for a quick test with ext4.

My guess:
Without US_FL_IGNORE_UAS (i.e. when using UAS),
the FUA command triggering the error is not used at all,
so US_FL_BROKEN_FUA doesn't make a difference.

> For that matter, does your kernel config include the uas driver?

Yes, it does.


I think we have to wait for sellis@redhat.com .
He could tell why he added US_FL_IGNORE_UAS,
if it's really needed, and why it was not included in mainline.

However, as US_FL_BROKEN_FUA is set for JMS567,
it is perhaps a good idea to set it for JMS566, too,
independent of US_FL_IGNORE_UAS (which is not set for JMS567).