On 01/27/2016 05:17 PM, Christian Seiler wrote: > Hi, > > While working on improvements w.r.t. open-iscsi userspace package in > Debian, I've stumbled upon a weird kernel bug in recent kernel > versions that makes the iSCSI initiator unusable. > > The test setup is quite simple: LIO target running on the host with > fileio backend (I tried both Debian Jessie host with 3.16 kernel and > Ubuntu 15.04 host with 3.19 kernel, no difference), initiator > running inside a libvirt/KVM instance (Debian sid); nothing special > about the setup otherwise. (The target itself shows no problems.)
So there are no other log messages on the LIO box? Something about max sectors being violated or a memory allocation failure? What kernel version is LIO running on in these tests? > > iSCSI login works perfectly fine, reading data from the iSCSI shows > no problems otherwise; writing small amounts of data to the iSCSI > device also works fine. But writing a bit more at once to the iSCSI > device will cause I/O errors in the kernel. > I think you are hitting a bug where the block layer is now sending really large IOs that LIO cannot handle or does not want to. There was a change in LIO to better tell the the initiator what size to use, so get the LIO kernel version so we can check that. You can still hit memory allocation failures in LIO and hit a similar issue, but with just a dd of 4MB IOs you should not hit the problem. -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/open-iscsi. For more options, visit https://groups.google.com/d/optout.
