Re: [ARM][xencons] PV Console hangs due to illegal ring buffer accesses

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Fri, 21 Jul 2023, Andrei Cherechesu (OSS) wrote:
> > I am really confused. I would try with regular Linux instead of Linux RT
> > and also would try to replace all the barriers in
> > drivers/tty/hvc/hvc_xen.c with their virt_* version to see if we can
> > narrow down the problem a bit.
> > 
> 
> Unfortunately, we do not normally run regular Linux and we do not have a
> stable regular Linux version with our HW support ported on it. We've been 
> running
> Linux RT since 4.14 (or even earlier I think), but this issue has started to 
> happen
> since we upgraded to Xen 4.17 (from 4.14), with both Linux RT 5.15 and 5.10.

I saw that George tried both suggestions without making progress.

This is a very difficult bug. If Xen 4.14 works and the issue starts
with Xen 4.17, then I would try to bisect it (try Xen 4.15, 4.16, etc.
until you narrow down the commit).