kern/132715: [lagg] [panic] Panic when creating vlan's on lagg interface

Maxim Ignatenko at
Mon Apr 20 16:20:04 UTC 2009

The following reply was made to PR kern/132715; it has been noted by GNATS.

From: Maxim Ignatenko < at>
To: bug-followup at, gdef at
Subject: Re: kern/132715: [lagg] [panic] Panic when creating vlan's on lagg 
Date: Mon, 20 Apr 2009 18:46:32 +0300

 This panic more likely related to em(4) than lagg. After adding vlan
 to interface other than em, if at least one em present, kernel panics
 on line
 ctrl = E1000_READ_REG(&adapter->hw, E1000_CTRL);
 in function em_register_vlan because of access to "struct adapter
 *adapter = ifp->if_softc", which was initialized by other driver.
 Here is cut from debugging session:
 Program received signal SIGSEGV, Segmentation fault.
 0xc04b4555 in em_register_vlan (unused=0x0, ifp=0xc2102000, vtag=100)
 at /usr/home/imax/work/head/sys/dev/e1000/if_em.c:4774
 4774            ctrl = E1000_READ_REG(&adapter->hw, E1000_CTRL);
 (kgdb) p ifp->if_xname
 $1 = "re0", '\0' <repeats 12 times>
 (kgdb) bt
 #0  0xc04b4555 in em_register_vlan (unused=0x0, ifp=0xc2102000,
 vtag=100) at /usr/home/imax/work/head/sys/dev/e1000/if_em.c:4774
 #1  0xc0647661 in vlan_config (ifv=0xc23de980, p=0xc2102000, tag=100)
 at /usr/home/imax/work/head/sys/net/if_vlan.c:1075
 #2  0xc06479e3 in vlan_clone_create (ifc=0xc086f5c0, name=0xc212f7a0
 "vlan0", len=16, params=0x80642d8 "re0") at
 #3  0xc063c221 in if_clone_createif (ifc=0xc086f5c0, name=0xc212f7a0
 "vlan0", len=16, params=0x80642d8 "re0") at
 #4  0xc063c48c in if_clone_create (name=0xc212f7a0 "vlan0", len=16,
 params=0x80642d8 "re0") at
 #5  0xc063b427 in ifioctl (so=0xc2251000, cmd=3223349628,
 data=0xc212f7a0 "vlan0", td=0xc2210690) at
 #6  0xc05de057 in soo_ioctl (fp=0xc2205070, cmd=3223349628,
 data=0xc212f7a0, active_cred=0xc2244a00, td=0xc2210690) at
 #7  0xc05d89cd in kern_ioctl (td=0xc2210690, fd=3, com=3223349628,
 data=0xc212f7a0 "vlan0") at file.h:262
 #8  0xc05d8b54 in ioctl (td=0xc2210690, uap=0xccf3dcf8) at
 #9  0xc07d6413 in syscall (frame=0xccf3dd38) at
 #10 0xc07c25a0 in Xint0x80_syscall () at
 #11 0x00000033 in ?? ()
 Previous frame inner to this frame (corrupt stack?)
 Unfortunately, now I don't know enough to fix this, I don't know even
 where thing begin going wrong. It would be nice if someone point me in
 right direction.

More information about the freebsd-net mailing list