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Subject: Re: head@r334204, Bad link elm in callout_process()
To: Andriy Gapon <avg@FreeBSD.org>,
 FreeBSD Current <freebsd-current@FreeBSD.org>
References: <d52aa0a9-7fbe-da6e-aa36-f34171e33843@FreeBSD.org>
From: Hans Petter Selasky <hps@selasky.org>
Message-ID: <84341ca3-90a5-97ef-8eee-dc1bbb07503c@selasky.org>
Date: Tue, 29 May 2018 13:53:08 +0200
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On 05/29/18 13:20, Andriy Gapon wrote:
> (kgdb) p *$4.lh_first->c_links.le.le_next
> $6 = {
>    c_links = {
>      le = {
>        le_next = 0x0,
>        le_prev = 0xfffffe0003999f98

Where does the le_prev point?

Typically happens when callouts are not properly drained before freeing 
memory.

--HPS