From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Albert D. Cahalan" Message-Id: <200103290610.f2T6A7s282810@saturn.cs.uml.edu> Subject: Re: [patch] pae-2.4.3-C3 Date: Thu, 29 Mar 2001 01:10:07 -0500 (EST) In-Reply-To: from "Ingo Molnar" at Mar 28, 2001 11:57:52 AM MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: mingo@elte.hu Cc: Linux Kernel List , linux-mm@kvack.org List-ID: Ingo Molnar writes: > the attached pae-2.4.3-C3 patch fixes the PAE code to work with SLAB > FORCED_DEBUG (which enables redzoning) too. > > the problem is that redzoning is enabled unconditionally, and SLAB has no > information about how crutial alignment is in the case of any particular > SLAB cache. The CPU generates a general protection fault if in PAE mode a > non-16-byte aligned pgd is loaded into %cr3. How about just fixing the debug code to align things? Sure it wastes a bit of memory, but debug code is like that. Sane alignment might be: largest power-of-two factor of the size, or 4 bytes, which ever is larger. (adjust "4" per-arch as needed) For an SMP config, set a minimum alignment equal to the cache line size. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux.eu.org/Linux-MM/