For me to replicate the problem I just login to the target using bnx2i. Just one instance of iscsiadm -m node --login using the bnx2i driver causes the problem.
I have been trying to replicate when adding debug comments in the kernel but that made the problem go away. I also tried getting a crash report but with that enabled the problem went away. On 07/22/2013 09:24 AM, Alex Lyakas wrote: > Hi Mike, > any advice on how to proceed further with this issue? > > Thanks, > Alex. > > > -----Original Message----- From: Alex Lyakas > Sent: 02 July, 2013 9:41 PM > To: Mike Christie ; open-iscsi@googlegroups.com > Cc: Lev Vainblat ; Yair Hershko > Subject: Re: NULL pointer deref in iscsi_sw_tcp_host_get_param > > Hi Mike, > For us it happened only once till now; and from our kernel log, I don't > think anything special was going on during that time, except that we were > reading the sysfs entry. Can you pls share how do you replicate the problem > with the Oracle kernel? If this narrows us down a bit on how to replicate, > then, yes, we can apply a debugging patch. > > One thing our application is doing, is to run several iscsiadm commands > (via > fork/exec) in parallel. Is this, in general, a safe thing to do, i.e., > running multiple iscsiadm processes in parallel? Each iscsiadm process > operates against a different iSCSI target. > > Thanks, > Alex. > > > -----Original Message----- From: Mike Christie > Sent: 02 July, 2013 8:23 PM > To: open-iscsi@googlegroups.com > Cc: Alex Lyakas ; Lev Vainblat ; Yair Hershko > Subject: Re: NULL pointer deref in iscsi_sw_tcp_host_get_param > > Hey, > > Is it easy for you to replicate this problem and if so would it be > possible to run with a patch that spits out some extra debugging info? > > It is easy for me to replicate with the Oracle linux kernel, but when I > add debugging it seems to move around or become difficult to hit. > > > On 06/27/2013 04:54 AM, Alex Lyakas wrote: >> Hello Mike, >> thank you for responding to my bug report. >> Here is the information you asked for: >> >> This issue happened within a virtual machine. The network interface, >> that is used for iscsi within the VM is a SR-IOV Virtual Function. The >> VM runs a stock ixgbevf driver from 3.8.13 mainline kernel. On the >> physical machine, the Virtual Function is spawned out of Intel 82599EB >> card. The ixgbe driver for the Intel card on the physical machine is >> 3.11.33. The physical machine runs stock Ubuntu Precise kernel >> "3.2.0-29-generic #46-Ubuntu", while the VM runs mainline 3.8.13 kernel. >> From within the VM, we connect to targets that live both on the same >> physical machine and on other physical machines. >> >> I am attaching a .config file for the VM kernel. We did not build the >> kernel ourselves, this is a mainline build done by Ubunti here: >> http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.8.13-raring/ >> I am also attaching the full kernel log with the information about the >> crash, it has more stack traces. >> >> The iscsiadm commands that we use (from another application via >> fork()/exec()) are: >> iscsiadm --mode node --portal <portal> --targetname <name> --op new >> iscsiadm --mode node --portal <portal> --targetname <name> --login >> iscsiadm --mode node --portal <portal> --targetname <name> --logout >> iscsiadm --mode node [--print <level>] >> iscsiadm --mode session [--print <level>] >> iscsiadm --mode host [--print <level>] >> >> Occasionally we also read sysfs attributes, with a script that collects >> all system's sysfs entries for further analysis. >> >> We use version 2.0-871 of open-iscsi, we install them via apt-get: >> dpkg -l: >> ii open-iscsi 2.0.871-0ubuntu9.12.04.1 >> High performance, transport independent iSCSI implementation >> ii open-iscsi-utils 2.0.871-0ubuntu9.12.04.1 >> iSCSI initiatior administrative utility >> >> We open one session to each target, but we connect to multiple targets. >> >> Please let me know if any other info is needed. >> >> Thanks for your help, >> Alex. >> >> >> -----Original Message----- From: Mike Christie >> Sent: 27 June, 2013 10:13 AM >> To: open-iscsi@googlegroups.com >> Cc: Alex Lyakas >> Subject: Re: NULL pointer deref in iscsi_sw_tcp_host_get_param >> >> On 06/26/2013 07:50 PM, Mike Christie wrote: >>> On 06/26/2013 05:27 PM, Mike Christie wrote: >>>> We have not seen it before. I am not seeing it here. >>> >>> Oh wait, I can hit it when using bnx2i and the OEL kernel >>> 2.6.39-400.17.1.el6uek.x86_64 kernel. I do not hit it with iscsi_tcp >>> though. Have not tried other upstream kernels with offload yet. >>> >> >> Huh. I tried upstream 2.6.39 to 3.8 and also 3.8.10 and could not hit >> the problem. I only hit it with that OEL kernel when using bnx2x. Also I >> hit the oops in a slightly different place. >> > -- 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 open-iscsi+unsubscr...@googlegroups.com. To post to this group, send email to open-iscsi@googlegroups.com. Visit this group at http://groups.google.com/group/open-iscsi. For more options, visit https://groups.google.com/groups/opt_out.
