From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LQsPA-0005RT-Dj for qemu-devel@nongnu.org; Sat, 24 Jan 2009 18:59:12 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LQsP9-0005Q8-N2 for qemu-devel@nongnu.org; Sat, 24 Jan 2009 18:59:12 -0500 Received: from [199.232.76.173] (port=59142 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LQsP9-0005Pu-Jp for qemu-devel@nongnu.org; Sat, 24 Jan 2009 18:59:11 -0500 Received: from hall.aurel32.net ([88.191.82.174]:32790) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1LQsP9-00014y-4U for qemu-devel@nongnu.org; Sat, 24 Jan 2009 18:59:11 -0500 Date: Sun, 25 Jan 2009 00:59:08 +0100 From: Aurelien Jarno Subject: Re: [Qemu-devel] [PATCH] Fix -kernel on target-ppc Message-ID: <20090124235908.GE16336@volta.aurel32.net> References: <1232830715-20476-1-git-send-email-agraf@suse.de> <20090124214840.GG19498@hall.aurel32.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexander Graf Cc: qemu-devel@nongnu.org On Sat, Jan 24, 2009 at 10:57:19PM +0100, Alexander Graf wrote: > > On 24.01.2009, at 22:48, Aurelien Jarno wrote: > >> On Sat, Jan 24, 2009 at 09:58:35PM +0100, Alexander Graf wrote: >>> OpenBIOS searches for the preloaded kernel at 0x1000000, so let's >>> put it there instead of an invalid location. >> >> Your patch is actually wrong, the second argument of load_elf() is an >> offset to the physical address (as found in the elf header), and not a >> load address. >> >> By chance the physical address of a >= 2.6.25 kernel is 0x00000000, so >> your patch works. But it will break supports for < 2.6.25 kernel as >> their physical address is 0xc0000000. Not that they are only the >> default >> values, they can be changed in the .config file. > > Aah, that explains why :-). > >> I have already proposed a patch to use the virtual address of the elf >> header as done by yaboot or quik, but I have been told it is actually >> wrong. >> >> We have to find another way to load the elf file at a fixed address. > > Hm - can't we just give load_elf an override value for the base address? > > /* address_offset is hack for kernel images that are > linked at the wrong physical address. */ > addr = ph->p_paddr + address_offset; > > cpu_physical_memory_write_rom(addr, data, mem_size); > > Just pass another variable here that overrides addr and doesn't > calculate it? Except that they can be more than one segment to load, so the last one will overwrite the previous ones. The PowerPC kernels I have seen only have one load segment, but I am not sure it is always the case. -- Aurelien Jarno GPG: 1024D/F1BCDB73 aurelien@aurel32.net http://www.aurel32.net