From patchwork Mon Mar 26 19:27:00 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: fix multiboot loading if load_end_addr == 0 From: Scott Moser X-Patchwork-Id: 148817 Message-Id: To: Anthony Liguori Cc: qemu-devel@nongnu.org Date: Mon, 26 Mar 2012 15:27:00 -0400 (EDT) The previous multiboot load code did not treat the case where load_end_addr was 0 specially. The multiboot specification says the following: * load_end_addr Contains the physical address of the end of the data segment. (load_end_addr - load_addr) specifies how much data to load. This implies that the text and data segments must be consecutive in the OS image; this is true for existing a.out executable formats. If this field is zero, the boot loader assumes that the text and data segments occupy the whole OS image file. Signed-off-by: Scott Moser diff --git a/hw/multiboot.c b/hw/multiboot.c index b4484a3..b1e04c5 100644 --- a/hw/multiboot.c +++ b/hw/multiboot.c @@ -202,10 +202,16 @@ int load_multiboot(void *fw_cfg, uint32_t mh_bss_end_addr = ldl_p(header+i+24); mh_load_addr = ldl_p(header+i+16); uint32_t mb_kernel_text_offset = i - (mh_header_addr - mh_load_addr); - uint32_t mb_load_size = mh_load_end_addr - mh_load_addr; - + uint32_t mb_load_size = 0; mh_entry_addr = ldl_p(header+i+28); - mb_kernel_size = mh_bss_end_addr - mh_load_addr; + + if (mh_load_end_addr) { + mb_kernel_size = mh_bss_end_addr - mh_load_addr; + mb_load_size = mh_load_end_addr - mh_load_addr; + } else { + mb_kernel_size = kernel_file_size - mb_kernel_text_offset; + mb_load_size = mb_kernel_size; + } /* Valid if mh_flags sets MULTIBOOT_HEADER_HAS_VBE. uint32_t mh_mode_type = ldl_p(header+i+32);