Kernel panic while “ modprobe amdkfd ; modprobe -r amdkfd ; 4.14.35 kernel

[John Donnelly]

Hello ,

I am investigating a issue reported by a test group concerning this driver.  Their test loads and unloads every kernel module included in the 4.14.35 kernel release . You don’t even need a AMD platform . It occurs on any Intel,  or a  KVM VM instance too. 

Kernel panic while “  modprobe amdkfd ;  modprobe -r amdkfd  “

[  329.425334]  ? __slab_free+0x9b/0x2ba
[  329.427836]  ? process_slab+0x3c1/0x45c
[  329.430336]  dev_printk_emit+0x4e/0x65
[  329.432829]  __dev_printk+0x46/0x8b
[  329.435183]  _dev_info+0x6c/0x85
[  329.437435]  ? kfree+0x141/0x182
[  329.439646]  kfd_module_exit+0x37/0x39 [amdkfd]
[  329.442258]  SyS_delete_module+0x1c3/0x26f
[  329.444722]  ? entry_SYSCALL_64_after_hwframe+0xaa/0x0
[  329.447479]  ? entry_SYSCALL_64_after_hwframe+0xa3/0x0
[  329.450206]  ? entry_SYSCALL_64_after_hwframe+0x9c/0x0
[  329.452912]  ? entry_SYSCALL_64_after_hwframe+0x95/0x0
[  329.455586]  do_syscall_64+0x79/0x1ae
[  329.457766]  entry_SYSCALL_64_after_hwframe+0x151/0x0
[  329.460369] RIP: 0033:0x7f1757a1b457
[  329.462502] RSP: 002b:00007ffd62ce1f48 EFLAGS: 00000206 ORIG_RAX:



Sometimes  the unload works but the message logged is garbage:

[root at jpd-vmbase02 ~]# modprobe -r amdkfd
[  144.449981] ???????????? hn??蟟??xn??ן??kfd: Removed module


Is  this something one of team members could have possibly corrected in an upstream version ?

#define KFD_DRIVER_DESC         "Standalone HSA driver for AMD's GPUs"
#define KFD_DRIVER_DATE         "20150421"
#define KFD_DRIVER_MAJOR        0
#define KFD_DRIVER_MINOR        7
#define KFD_DRIVER_PATCHLEVEL   2


Any advise welcome. 


Thank you,

John