Re: Linux 2.6.36-rc7

[Tvrtko Ursulin <tvrtko.ursulin@sophos.com>]

On Thursday 07 Oct 2010 17:10:46 Tvrtko Ursulin wrote:
> On Wednesday 06 Oct 2010 22:45:13 Linus Torvalds wrote:
> [snip]
>
> > And yes, that's probably as exciting as it gets, which is just fine by
> > me. This should be the last -rc, I'm not seeing any reason to keep
> > delaying a real release. There was still more changes to
> > drivers/gpu/drm than I really would have hoped for, but they all look
> > harmless and good. Famous last words.
>
> Hi Linus,
>
> Please see http://marc.info/?l=linux-kernel&m=128618485204253&w=2
>
> I have sent this proposed bugfix several times now but no one is picking it
> up and Eric seems to have disappeared. It would be suboptimal to release
> 2.6.36 with a core fanotify feature non-functional.

Unfortunately I have another showstopper. Sadly I missed it until now because
internally we were more worried of issues which were kind of direct problems
for us and I went to deep instead of spending more time reviewing it breath
first.

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=08ae89380a8210a9965d04083e1de78cb8bca4b1

Priority argument was dropped from the fanotify_init syscall, and since it is
a syscall once released it is set in stone. Without the priority argument, how
are multiple clients supposed to be ordered?

Co-existence between multiple clients was something which was supposed to be
designed in from the start. Use cases like hierarchical storage management,
anti-malware and content indexing should all be able to co-exist. Without a
priority argument I do not see how it can be assured HSM sees the perm event
before anti-malware, and content indexing after both of them? If there was any
discussion about dropping priority I missed it. :(

Tvrtko

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