On 21.11.2013, at 13:24, Cornelia Huck <cornelia.h...@de.ibm.com> wrote:
> On Thu, 21 Nov 2013 14:08:22 +0200 > "Michael S. Tsirkin" <m...@redhat.com> wrote: > >> pc-bios/s390-zipl.rom is a flat image so it's expected that >> loading it as elf will fail. >> It should fall back on loading a flat file, but doesn't >> on 32 bit systems, instead it fails printing: >> qemu: hardware error: could not load bootloader 's390-zipl.rom' >> >> The result is boot failure. >> >> The reason is that a 64 bit unsigned interger which is set >> to -1 on error is compared to -1UL which on a 32 bit system >> with gcc is a 32 bit unsigned interger. >> Since both are unsigned, no sign extension takes place and >> comparison evaluates to non-equal. >> >> There's no reason to do clever tricks: -1 will cause >> sign extension to happen correctly automatically. >> >> Signed-off-by: Michael S. Tsirkin <m...@redhat.com> >> --- >> hw/s390x/ipl.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c >> index d69adb2..88115e9 100644 >> --- a/hw/s390x/ipl.c >> +++ b/hw/s390x/ipl.c >> @@ -80,7 +80,7 @@ static int s390_ipl_init(SysBusDevice *dev) >> >> bios_size = load_elf(bios_filename, NULL, NULL, &ipl->start_addr, >> NULL, >> NULL, 1, ELF_MACHINE, 0); >> - if (bios_size == -1UL) { >> + if (bios_size == -1) { >> bios_size = load_image_targphys(bios_filename, ZIPL_IMAGE_START, >> 4096); >> ipl->start_addr = ZIPL_IMAGE_START; > > Makes sense, but doesn't the kernel loader just below suffer from just > the same problem? Yes, initrd too. Alex