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From: Adrian Chadd <adrian@freebsd.org>
To: "Alexander V. Chernikov" <melifaro@freebsd.org>
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Subject: Re: svn commit: r233937 - in head/sys: kern net security/mac
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On 15 April 2012 23:33, Alexander V. Chernikov <melifaro@freebsd.org> wrote:
> On 16.04.2012 01:17, Adrian Chadd wrote:
>>
>> Hi,
>>
>> This has broken (at least) net80211 and bpf, with LOR:
>
> Yes, it is. Please try the attached patch

Hi,

This seems like a very, very complicated diff.

* You've removed BPF_LOCK_ASSERT() inside bpf_detachd_locked() - why'd
you do that?
* You removed a comment ("We're already protected by the global lock")
which is still relevant/valid
* There are lots of modifications to the read/write locks here - I'm
not sure whether they're at all relevant to my immediate problem and
may belong in separate commits

Is there a document somewhere which describes what the "new" style BPF
locking should be?

I "just" added BPF_LOCK() / BPF_UNLOCK() around all the calls to
bpf_detachd() which weren't locked (there were a few.)

One final question - should the BPF global lock be recursive?

thanks,



Adrian