Re: modprobe mlx5_core on OCI bare-metal instance causes unrecoverable hang and I/O error

[Mitchell Augustin]

> Is it using iscsi/srp/nfs/etc for any filesystems?

Yes, dev sda is using iSCSI:

ubuntu@inst-v4ovk-mitchell-instance-pool-20250205-1119:~$ sudo
iscsiadm -m session -P 3
iSCSI Transport Class version 2.0-870
version 2.1.9
Target: iqn.2015-02.oracle.boot:uefi (non-flash)
Current Portal: 169.254.0.2:3260,1
Persistent Portal: 169.254.0.2:3260,1
**********
Interface:
**********
Iface Name: default
Iface Transport: tcp
Iface Initiatorname: iqn.2010-04.org.ipxe:080020ff-ffff-ffff-ffff-a8698c179e5c
Iface IPaddress: 10.0.0.254
Iface HWaddress: default
Iface Netdev: default
SID: 1
iSCSI Connection State: LOGGED IN
iSCSI Session State: LOGGED_IN
Internal iscsid Session State: NO CHANGE
*********
Timeouts:
*********
Recovery Timeout: 6000
Target Reset Timeout: 30
LUN Reset Timeout: 30
Abort Timeout: 15
*****
CHAP:
*****
username: <empty>
password: ********
username_in: <empty>
password_in: ********
************************
Negotiated iSCSI params:
************************
HeaderDigest: None
DataDigest: None
MaxRecvDataSegmentLength: 262144
MaxXmitDataSegmentLength: 8192
FirstBurstLength: 65536
MaxBurstLength: 262144
ImmediateData: Yes
InitialR2T: Yes
MaxOutstandingR2T: 1
************************
Attached SCSI devices:
************************
Host Number: 0 State: running
scsi0 Channel 00 Id 0 Lun: 0
scsi0 Channel 00 Id 0 Lun: 1
Attached scsi disk sda State: running



On Fri, Feb 7, 2025 at 9:55 AM Jason Gunthorpe <jgg@xxxxxxxx> wrote:
>
> On Wed, Feb 05, 2025 at 05:09:13PM -0600, Mitchell Augustin wrote:
> > Hello,
> >
> > I have identified a bug in the mlx5_core module, or some related component.
> >
> > Doing the following on a freshly provisioned Oracle Cloud bare metal
> > node with this configuration [0] will reliably cause the entire
> > instance to become unresponsive:
> >
> > rmmod mlx5_ib; rmmod mlx5_core; modprobe mlx5_core
> >
> > This also produces the following output:
> >
> > [  331.267175] I/O error, dev sda, sector 35602992 op 0x0:(READ) flags
> > 0x80700 phys_seg 33 prio class 0
>
> Is it using iscsi/srp/nfs/etc for any filesystems?
>
> Jason



-- 
Mitchell Augustin
Software Engineer - Ubuntu Partner Engineering