From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Stephen C. Tweedie" MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <14338.1425.683604.262468@dukat.scot.redhat.com> Date: Mon, 11 Oct 1999 16:43:13 +0100 (BST) Subject: Re: locking question: do_mmap(), do_munmap() In-Reply-To: References: Sender: owner-linux-mm@kvack.org Return-Path: To: Andrea Arcangeli Cc: Alexander Viro , Manfred Spraul , linux-kernel@vger.rutgers.edu, Ingo Molnar , linux-mm@kvack.org, Stephen Tweedie List-ID: Hi, On Sun, 10 Oct 1999 19:12:58 +0200 (CEST), Andrea Arcangeli said: > The other option is to make the mmap semaphore recursive checking that GFP > is not called in the middle of a vma change. I don't like this one it sound > not robust as the spinlock way to me (see below). Doesn't work, because you can still have a process which takes one mmap semaphore and then attempts to take a different one inside the swapper as the result of a memory allocation. As soon as you have two processes doing that to each other's semaphores, you still have a deadlock. --Stephen -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://humbolt.geo.uu.nl/Linux-MM/