From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from localhost (localhost [127.0.0.1]) by baldur.austin.ibm.com (8.12.9/8.12.9/Debian-3) with ESMTP id h4SFRqFA012371 for ; Wed, 28 May 2003 10:27:53 -0500 Date: Wed, 28 May 2003 10:27:52 -0500 From: Dave McCracken Subject: Question about locking in mmap.c Message-ID: <33460000.1054135672@baldur.austin.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: owner-linux-mm@kvack.org Return-Path: To: Linux Memory Management List-ID: It's been my understanding that most vma manipulation is protected by mm->mmap_sem, and the page table is protected by mm->page_table_lock. I've been rummaging through mmap.c and see a number of places that take page_table_lock when the code is about to make changes to the vma chains. These places are already holding mmap_sem for write. My question is what is page_table_lock supposed to be protecting against? Am I wrong that mmap_sem is sufficient to protect against concurrent changes to the vmas? Dave McCracken ====================================================================== Dave McCracken IBM Linux Base Kernel Team 1-512-838-3059 dmccr@us.ibm.com T/L 678-3059 -- 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-mm.org/ . Don't email: aart@kvack.org