From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 31 May 2002 17:15:50 +1000 From: David Gibson To: linuxppc-embedded@lists.linuxppc.org Subject: CONFIG_PIN_TLB and telnet problems Message-ID: <20020531071550.GF16537@zax> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: Ok, I think I've managed to reproduce the telnet problems with CONFIG_PIN_TLB that Tom Rini and others have reported. I encountered problems telnetting to localhost on a 16MB EP405 (PVR 40110145) and on a 32MB Walnut (PVR 401100C4). I was unable to reproduce the problem on any of the other 405GP machines I have, each of which as at least 64MB of RAM. Interestingly, if I alter the CONFIG_PIN_TLB code so that it only pins one entry (i.e. maps 16MB of RAM instead of 32MB) I can still reproduce the problem on the EP405, but not on the Walnut. It would seem the problem only bites if the pinned allocation is as large or larger than physical memory. It's vaguely understandable that with two pinned entries it would break on the 16MB machine: creating a mapping for more RAM than exists is certainly a bug. I don't yet know why there is a problem when the mapping is exactly as large as RAM though. -- David Gibson | For every complex problem there is a david@gibson.dropbear.id.au | solution which is simple, neat and | wrong. -- H.L. Mencken http://www.ozlabs.org/people/dgibson ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/