From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1IiDyv-0006Up-Aj for qemu-devel@nongnu.org; Wed, 17 Oct 2007 14:51:01 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1IiDys-0006TB-H5 for qemu-devel@nongnu.org; Wed, 17 Oct 2007 14:51:00 -0400 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1IiDys-0006T7-DZ for qemu-devel@nongnu.org; Wed, 17 Oct 2007 14:50:58 -0400 Received: from honiara.magic.fr ([195.154.193.36]) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1IiDyr-0000b8-C9 for qemu-devel@nongnu.org; Wed, 17 Oct 2007 14:50:58 -0400 Subject: Re: [Qemu-devel] Mips target '-kernel' option bug From: Jocelyn Mayer In-Reply-To: <20071017135148.GZ3379@networkno.de> References: <1192568594.9976.523.camel@rapid> <20071017135148.GZ3379@networkno.de> Content-Type: text/plain Date: Wed, 17 Oct 2007 20:50:54 +0200 Message-Id: <1192647054.32421.41.camel@jma4.dev.netgem.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Reply-To: l_indien@magic.fr, qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Thiemo Seufer Cc: qemu-devel@nongnu.org On Wed, 2007-10-17 at 14:51 +0100, Thiemo Seufer wrote: > J. Mayer wrote: > > I failed to run Mips target test image on my amd64 machine and I now > > found the reason of the bug: > > the kernel loader code used in hw/mips_r4k.c and hw/mips_malta.c > > implicitelly assumes that the ram_addr_t is 32 bits long. > > Unfortunatelly, on 64 bits hosts, this won't be the case and the kernel > > load address then is over 4 GB. Then, when computing the initrd_offset, > > the code always concludes that there's not enough RAM available to load > > it at the top of the kernel. > > I found 2 ways of fixing the bug, but I don't know which one is correct > > in Mips execution environment. > > The first patch is to make the VIRT_TO_PHYS_ADDEND negative, thus > > translating the kernel virtual address from 0x8000nnnn to the physical > > one 0x0000nnnn (instead of 0x10000nnnn, when running on 64 bits hosts). > > The second solution would be to explicitelly always cast the kernel_high > > value to 32 bits. > > As I do not really know if some Mips target specific constraints would > > make one of the other solution prefered, I'd better let the specialist > > choose ! > > > > The good news is that, once this issue is fixed, the Mips test images > > run with the reverse-endian softmmu patch applied. > > I think this patch is the correct fix. Please test and comment. Thanks, I'll test it at home tonight. To satisfy my curiosity, is there a specific reason to have a positive VIRT_TO_PHYS_ADDEND ? [...]