Issue

A kernel oops happens when loading Chelsio cxgb4 driver on RHEL7

The call trace is :

[   91.636713] Call Trace:
[   91.639176]  [<ffffffff812c2e3b>] string.isra.5+0x3b/0xf0
[   91.644576]  [<ffffffff812c4371>] vsnprintf+0x201/0x6a0
[   91.649812]  [<ffffffff814fdfff>] ? nlmsg_notify+0x4f/0xb0
[   91.655301]  [<ffffffff812c4996>] sprintf+0x56/0x80
[   91.660196]  [<ffffffffa0495354>] init_one+0xb64/0x1310 [cxgb4]
[   91.666123]  [<ffffffff8101a603>] ? native_sched_clock+0x13/0x80
[   91.672146]  [<ffffffff812eaf45>] local_pci_probe+0x45/0xa0
[   91.677714]  [<ffffffff8107af14>] work_for_cpu_fn+0x14/0x20
[   91.683287]  [<ffffffff8107e02b>] process_one_work+0x17b/0x460
[   91.689115]  [<ffffffff8107ef73>] worker_thread+0x293/0x400
[   91.694680]  [<ffffffff8107ece0>] ? rescuer_thread+0x400/0x400
[   91.700529]  [<ffffffff81085aef>] kthread+0xcf/0xe0
[   91.705406]  [<ffffffff81085a20>] ? kthread_create_on_node+0x140/0x140
[   91.711949]  [<ffffffff815f206c>] ret_from_fork+0x7c/0xb0
[   91.717351]  [<ffffffff81085a20>] ? kthread_create_on_node+0x140/0x140
[   91.723871] Code: c0 01 80 38 00 75 f7 48 29 f8 5d c3 31 c0 5d c3 66 
66 66 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 85 f6 48 8d 4e ff 48 89 e5 
74 2a <80> 3f 00 74 25 48 89 f8 31 d2 eb 10 0f 1f 80 00 00 00 00 48 83
[   91.743846] RIP  [<ffffffff812c0a3d>] strnlen+0xd/0x40
[   91.748997]  RSP <ffff8808534d3bf0>
[   91.752490] CR2: 0000123c000011fc

The machine boots when blacklisting modules cxbg4, csiostor
(modprobe.blacklist=cxgb4 modprobe.blacklist=csiostor).

The same card works OK and the machine boots when a newer version of the
Chelsio drivers is used (2.9.1.0).