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From: Chris Friesen <cfriesen@nortelnetworks.com>
To: Jeff Dike <jdike@addtoit.com>
Cc: User-mode-linux-devel <User-mode-linux-devel@lists.sourceforge.net>
Subject: [uml-devel] Re: problems with UML, issues with includes
Date: Tue, 02 Mar 2004 18:03:11 -0500	[thread overview]
Message-ID: <404512AF.1070309@nortelnetworks.com> (raw)
In-Reply-To: 200403022054.i22KslWo003006@ccure.user-mode-linux.org


Further update on the very strange behaviour I'm seeing.

I instrumented kfree() as mentioned before, and also instrumented 
activate_fd() to test after um_kmalloc() whether the result was already 
in the active_fds list.

I had assumed that I would see it being freed while still on the list, 
then being returned from malloc the next time around, causing a dupe.

However, what I actually saw was


new fd is same address as one already in active_fds
deleting address currently in active_fds


In other words, the um_kmalloc() was returning an address already in the 
active_fds list, *before* an address still in the list had been 
kfree()'d.  The kfree() that I see with an address in the list is the 
one from the out_unlock jump target in activeate_fd().

So somehow um_kmalloc() is returning duplicate addresses without an 
intervening call to kfree().

Any ideas?

Chris




-- 
Chris Friesen                    | MailStop: 043/33/F10
Nortel Networks                  | work: (613) 765-0557
3500 Carling Avenue              | fax:  (613) 765-2986
Nepean, ON K2H 8E9 Canada        | email: cfriesen@nortelnetworks.com



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      parent reply	other threads:[~2004-03-02 23:16 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-03-01 22:07 [uml-devel] problems with UML, issues with includes Chris Friesen
2004-03-02  1:00 ` [uml-devel] " Jeff Dike
2004-03-02 15:08   ` Chris Friesen
2004-03-02 18:06     ` BlaisorBlade
2004-03-02 20:54     ` Jeff Dike
2004-03-02 22:26       ` Chris Friesen
2004-03-02 23:22         ` Jeff Dike
2004-03-02 23:18           ` Chris Friesen
2004-03-02 23:37           ` [uml-devel] Re: problems with UML -- new data with memory debugging on Chris Friesen
2004-03-03  1:33             ` Jeff Dike
2004-03-03 16:49               ` Chris Friesen
2004-03-08 21:34                 ` Jeff Dike
2004-03-08 21:08                   ` Chris Friesen
2004-03-02 23:03       ` Chris Friesen [this message]

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