From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sun, 25 Mar 2001 17:33:44 +0100 From: Russell King Subject: Re: [patch] pae-2.4.3-A4 Message-ID: <20010325173344.B30655@flint.arm.linux.org.uk> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: ; from mingo@elte.hu on Sun, Mar 25, 2001 at 04:53:37PM +0200 Sender: owner-linux-mm@kvack.org Return-Path: To: Ingo Molnar Cc: Linus Torvalds , Alan Cox , linux-mm@kvack.org, Linux Kernel List List-ID: On Sun, Mar 25, 2001 at 04:53:37PM +0200, Ingo Molnar wrote: > one nontrivial issue was that on PAE the pgd has to be installed with > 'present' pgd entries, due to a CPU erratum. This means that the > pgd_present() code in mm/memory.c, while correct theoretically, doesnt > work with PAE. An equivalent solution is to use !pgd_none(), which also > works with the PAE workaround. Certainly that's the way the original *_alloc routines used to work. In fact, ARM never had need to implement the pmd_present() macros, since they were never referenced - only the pmd_none() macros were. However, I'm currently struggling with this change on ARM - so far after a number of hours trying to kick something into shape, I've not managed to even get to the stange where I get a kernel image to link, let alone the compilation to finish. One of my many dilemas at the moment is how to allocate the page 0 PMD in pgd_alloc(), where we don't have a mm_struct to do the locking against. -- Russell King (rmk@arm.linux.org.uk) The developer of ARM Linux http://www.arm.linux.org.uk/personal/aboutme.html -- 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/