From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1EKfUW-0007gv-LZ for user-mode-linux-devel@lists.sourceforge.net; Wed, 28 Sep 2005 10:13:12 -0700 Received: from lakshmi.addtoit.com ([198.99.130.6] helo=lakshmi.solana.com) by mail.sourceforge.net with esmtp (Exim 4.44) id 1EKfUR-00085M-76 for user-mode-linux-devel@lists.sourceforge.net; Wed, 28 Sep 2005 10:13:09 -0700 From: Jeff Dike Subject: Re: [uml-devel] a question about sigsetjmp() in copy_from/to_user() Message-ID: <20050928160946.GB12888@ccure.user-mode-linux.org> References: <3524bf1f050927070645b999bd@mail.gmail.com> <20050927172812.GA28528@ccure.user-mode-linux.org> <200509281359.48449.blaisorblade@yahoo.it> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200509281359.48449.blaisorblade@yahoo.it> Sender: user-mode-linux-devel-admin@lists.sourceforge.net Errors-To: user-mode-linux-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: The user-mode Linux development list List-Post: List-Help: List-Subscribe: , List-Archive: Date: Wed, 28 Sep 2005 12:09:46 -0400 To: Blaisorblade Cc: user-mode-linux-devel@lists.sourceforge.net, Young Koh On Wed, Sep 28, 2005 at 01:59:48PM +0200, Blaisorblade wrote: > That wasn't the original reason - this is fine too, but as I explained in the > other mail, cat /dev/kmem will cause a copy_to_user() with invalid kernel > ("from") address. I remember because I discussed this with you at length. Oh yeah. I was thinking there was a different (and better) reason, but I couldn't remember what it was. Also, my reason isn't that good anyway. I had a different fix a while ago, but it got lost somewhere. I added an arch hook to get_free_pages which touched each allocated page under the cover of a setjmp. If a page couldn't be allocated on the host, then it is put on a "bad pages" list, and another page is allocated instead. Jeff ------------------------------------------------------- This SF.Net email is sponsored by: Power Architecture Resource Center: Free content, downloads, discussions, and more. http://solutions.newsforge.com/ibmarch.tmpl _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel