From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1IfgpT-0006Dd-PM for qemu-devel@nongnu.org; Wed, 10 Oct 2007 15:02:47 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1IfgpQ-0006DQ-DO for qemu-devel@nongnu.org; Wed, 10 Oct 2007 15:02:46 -0400 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1IfgpQ-0006DN-7r for qemu-devel@nongnu.org; Wed, 10 Oct 2007 15:02:44 -0400 Received: from nf-out-0910.google.com ([64.233.182.184]) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1IfgpP-00078j-RB for qemu-devel@nongnu.org; Wed, 10 Oct 2007 15:02:44 -0400 Received: by nf-out-0910.google.com with SMTP id 30so291031nfu for ; Wed, 10 Oct 2007 12:02:42 -0700 (PDT) Message-ID: Date: Wed, 10 Oct 2007 22:02:41 +0300 From: "Blue Swirl" Subject: Re: [Qemu-devel] RFC: fix run of 32 bits Linux executables on 64 bits targets In-Reply-To: <470D1C9A.2000505@bellard.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <1192002128.9976.186.camel@rapid> <470C8AD9.6000002@bellard.org> <20071010174906.GC3379@networkno.de> <470D1C9A.2000505@bellard.org> Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org On 10/10/07, Fabrice Bellard wrote: > Thiemo Seufer wrote: > > Fabrice Bellard wrote: > >> J. Mayer wrote: > >>> Following the patches done for elfload32, it appeared to me that there > >>> were still problems that would prevent 32 bits executables to run on 64 > >>> bits target in linux user mode emulation. > >>> [...] > >> Are you sure it is a good idea to try to add 32 bit executable support to a > >> 64 bit target ? In the end you will need to write a 64 bit to 32 bit linux > >> syscall converter which would mean duplicating all the linux-user code of > >> the corresponding 32 bit target (think of ioctls with strutures, signals > >> frames, etc...). > > > > I would think this feature will be limited to platforms which can handle > > 32bit and 64bit binaries with a single personality. > > I am not sure it is a common case ! > > However, I suggest to emulate a 32 bit user linux system with a 64 bit > guest CPU running in 32 bit compatibily mode. It would be useful to test > 64 bit CPUs in 32 bit compatibility mode. The only required modification > in linux user is to rename target_ulong so that it can have a different > size of the CPU word default size. I think this would be sufficient for the Sparc and this way there would be no need to convert the structures. Brilliant! Should we revert the elfload32 patch? What about PPC?