[ removed cc: stable from discussion ] On Wed, 2017-06-28 at 09:38 +0200, Johannes Thumshirn wrote: > > Looks good, > Reviewed-by: Johannes Thumshirn <jthumshirn@xxxxxxx> > > Although we've been tampering with the target removal code for quite some > time now, so I really have the gut feeling we haven't really fixed the > root cause yet. > > I once tried building a regression test for this (with qemu hot plugging UAS > devices) but that didn't really go far. Maybe we should add a scsi_target > to scsi_debug and add some methods to toggle remove it again. Just to have > a sensible unit test for that code path. > > Byte, > Johannes > This specific crash is being encountered on systems connected to flaky SANs, where the target rport repeatedly goes away. I was able to reproduce it by inserting a delay before the "Scan LUN 0" comment in __scsi_scan_target() with a message, and disabling the FC switch port. -Ewan
