kern/55699: Panic certainly in iSCSI initiator

[joel.bertrand%systella.fr@localhost]

>Number:         55699
>Category:       kern
>Synopsis:       Panic certainly in iSCSI initiator
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Oct 07 12:10:00 +0000 2020
>Originator:     joel.bertrand%systella.fr@localhost
>Release:        NetBSD 9.0_STABLE
>Organization:
>Environment:
	
	
System: NetBSD legendre.systella.fr 9.0_STABLE NetBSD 9.0_STABLE (CUSTOM) #13: Tue Oct 6 14:45:51 CEST 2020 root%legendre.systella.fr@localhost:/usr/src/netbsd-9/obj/sys/arch/amd64/compile/CUSTOM amd64
Architecture: x86_64
Machine: amd64
>Description:

	Hello,

	I have installed bacula on a NetBSD-9 server (dir, fd and sd). Bacula saves
data on a NAS (QNAP) directly connected through a specific ethernet adapter.

	Topology :
- wm0 : WAN
- agr0 (wm1+wm2) LAN
- re0 : to NAS (RTL8169 PCI Gigabit Ethernet Controller [10ec:8169] (rev 10))
- bridge0 (tap0+tap1) : remote access

	Randomly, when bacula lauches a job, system panics with :
[  3409.124192] uvm_fault(0xffffffff8151f760, 0xffffffff819ca000, 4) -> e
[  3409.124192] fatal page fault in supervisor mode
[  3409.124192] trap type 6 code 0x10 rip 0xffffffff819ca061 cs 0x8 rflags
0x10293 cr2 0xffffffff819ca061 ilevel 0 rsp 0xffffae013d79abb0
[  3409.124192] curlwp 0xfffffa749e1ef060 pid 160.1 lowest kstack
0xffffae013d7982c0
[  3409.124192] panic: trap
[  3409.124192] cpu5: Begin traceback...
[  3409.133355] vpanic() at netbsd:vpanic+0x160
[  3409.133355] snprintf() at netbsd:snprintf
[  3409.133355] startlwp() at netbsd:startlwp
[  3409.133355] alltraps() at netbsd:alltraps+0xbb
[  3409.133355] usbd_devinfo_vp() at netbsd:usbd_devinfo_vp+0xa9
[  3409.143358] usbd_fill_deviceinfo() at netbsd:usbd_fill_deviceinfo+0x68
[  3409.143358] usbioctl() at netbsd:usbioctl+0xdc
[  3409.143358] cdev_ioctl() at netbsd:cdev_ioctl+0xc4
[  3409.153361] VOP_IOCTL() at netbsd:VOP_IOCTL+0x54
[  3409.153361] vn_ioctl() at netbsd:vn_ioctl+0xa5
[  3409.153361] sys_ioctl() at netbsd:sys_ioctl+0x5ab
[  3409.163364] syscall() at netbsd:syscall+0x157
[  3409.163364] --- syscall (number 54) ---
[  3409.163364] 735f5396824a:
[  3409.163364] cpu5: End traceback...

[  3409.163364] dumping to dev 18,1 (offset=251919, size=4162814):

	Of course, I don't have any information in /var/crash. But I have
netbsd.gdb if required.

>How-To-Repeat:

	Connect an iSCSI target with iscsictl and generate huge traffic on iSCSI
device.

>Fix:

>Unformatted: