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To: mdean <mdean@best.com>
cc: freebsd-hackers@freebsd.org
Subject: Re: free() in device drivers 
In-reply-to: Your message of "Thu, 09 Oct 1997 20:11:25 MST."
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Date: Fri, 10 Oct 1997 13:17:04 +0930
From: Mike Smith <mike@smith.net.au>
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> 
> If I do a malloc (p, M_DEVBUF, M_NOWAIT);
> 
> then find a problem in my attach routine, can I do a free(p, M_DEVBUF) to
> recover that memory?

No.  In fact, the memory will remain allocated over even cold 
reboots, and you will have to open the system, identify which SIMM the 
memory was allocated on, remove it and wrap it in aluminium foil for 
half an hour to discharge the DRAM capacitors and clear the allocation.

mike