kern/183835: Kernel panic with VIMAGE on insertion of axe USB network interface

[小野寛生]

The following reply was made to PR kern/183835; it has been noted by GNATS.

From: =?ISO-2022-JP?B?GyRCPi5MbjQyQDgbKEI=?= <hiroo.ono at gmail.com>
To: bug-followup at FreeBSD.org, elakin at infohell.net
Cc:  
Subject: Re: kern/183835: Kernel panic with VIMAGE on insertion of axe USB
 network interface
Date: Sun, 2 Feb 2014 01:37:35 +0900

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 Attached patch for src/sys/net/if.c makes if_axe work with VIMAGE.
 Though I do not understand well why it works...
 
 curvnet is allocated in src/sys/net/vnet.c:vnet0_init() and then
 substituted to NULL in vnet.c:vnet_init_done()
 I guess that devices that are persistent are if_alloc()'ed in between
 the two functions are called,
 but if_alloc() for removable devices like if_axe occurs after vnet_init_done().
 (if is is right, creating vnet first and plugging the device in may
 not cause the kernel panic, but I did not test this idea.)
 
 Moreover, with this patch, error messages below occur when destroying
 epair device, so it does not seem to be the proper solution.
 
 Freed UMA keg (udp_inpcb) was not empty (128 items). Lost 8 pages of memory.
 Freed UMA keg (udpcb) was not empty (252 items). Lost 1 pages of memory.
 Freed UMA keg (tcp_inpcb) was not empty (128 items). Lost 8 pages of memory.
 Freed UMA keg (tcpcb) was not empty (30 items). Lost 6 pages of memory.
 hhook_vnet_uninit: hhook_head type=1, id=1 cleanup required
 hhook_vnet_uninit: hhook_head type=1, id=0 cleanup required
 
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