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Date: Wed, 03 Dec 2014 10:33:14 +0800
From: Julian Elischer <julian@freebsd.org>
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To: Warner Losh <imp@bsdimp.com>
Subject: Re: witness and modules.
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On 12/3/14, 12:24 AM, Warner Losh wrote:
>> On Dec 1, 2014, at 10:08 PM, Julian Elischer <julian@freebsd.org> wrote:
>>
>> On 12/1/14, 11:39 PM, John Baldwin wrote:
>>> On Friday, November 28, 2014 11:08:35 PM Julian Elischer wrote:
>>>> Do we need to compile all modules with witness definitions when
>>>> linking with a kernel compiled with witness?
>>>> This was true at one stage but I remember some work was done to make
>>>> them compatible.
>>> You should not need this.  modules always call functions in the kernel for
>>> lock operations and this functions are what invoke WITNESS.
>>>
>> that's what I thought but empirical evidence disagrees.
>> I'll try some more cases.
> I swap back and forth all the time between the two. Kernel modules don’t
> change when you compile them with WITNESS or without.
not entirely..
hwpmc.ko:                 U witness_restore
hwpmc.ko:                 U witness_save
zfs.ko:                 U witness_restore
zfs.ko:                 U witness_save
> Warner
>