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From: "Robert N. M. Watson" <rwatson@freebsd.org>
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Date: Mon, 12 Oct 2009 14:46:03 +0100
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To: Harsha <inpcb.harsha@gmail.com>
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Subject: Re: Page fault in IFNET_WLOCK_ASSERT [if.c and pccbb.c]
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On 12 Oct 2009, at 05:38, Harsha wrote:

> Thanks a lot for the clarification.
>
> I had assumed that the lock was non-sleepable looking at this log -
> Kernel page fault with the following non-sleepable locks held:
> exclusive rw ifnet_rw (ifnet_rw) r = 0 (0xc0f63464) locked @
> /usr/src/sys/net/if.c:409

Looks like a NULL pointer dereference, so perhaps a more traditional  
bug -- could you convert ifindex_alloc_locked+0x71 to a line of code?  
You can do this using kgdb on the kernel symbols file, perhaps "l  
*ifindex_alloc_locked+0x71".

Robert