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Date: Mon, 25 Nov 2002 14:36:03 -0800 (PST)
From: Davide Libenzi <davidel@xmailserver.org>
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To: John Myers <jgmyers@netscape.com>
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Subject: Re: [rfc] new poll callback'd wake up hell ...
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On Mon, 25 Nov 2002, John Myers wrote:

> Davide Libenzi writes:
>  > 1) Move the wake_up() call done inside the poll callback outside the lock
>
> You can't.  You need to hold the lock over the callback or your callback
> could end up accessing a freed epitem.

No, look at the code :

http://www.xmailserver.org/linux-patches/sys_epoll-2.5.49-0.58.diff

The function ep_collect_ready_items() increases the usage count under
lock. So the epintem is protected, and the file* cannot desappear because
of the read lock on epsem.



- Davide

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