On 25 March 2014 03:34, Joel Fernandes <jo...@ti.com> wrote: > Loading kernel at offset 0x10000 works only for zImage, but not for Image, > because the kernel expect the start of decompressed kernel (.head.text) to be > at an address that's a distance that's 16MB aligned from PAGE_OFFSET + > TEXT_OFFSET (see vmlinux.lds.S). This check is enfornced in __fixup_pv_table > in > arch/arm/kernel/head.S TEXT_OFFSET is 0x00008000, so a 16MB alignment needs to > have a "0x8000" in the lower 16 bits so that they cancel out. Currently the > offset Qemu loads it at is 0x10000. > > With zImage, this need is met because zImage loads the uncompressed Image > correctly, however when loading an Image and executing directly Qemu is > required it to load it at the correct location. Doing so, doesn't break Qemu's > zImage loading. With this patch, both zImage and Image work correctly. > > Signed-off-by: Joel Fernandes <jo...@ti.com> > --- > hw/arm/boot.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/hw/arm/boot.c b/hw/arm/boot.c > index dc62918..566b5c2 100644 > --- a/hw/arm/boot.c > +++ b/hw/arm/boot.c > @@ -23,7 +23,7 @@ > * They have different preferred image load offsets from system RAM base. > */ > #define KERNEL_ARGS_ADDR 0x100 > -#define KERNEL_LOAD_ADDR 0x00010000 > +#define KERNEL_LOAD_ADDR 0x00008000 > #define KERNEL64_LOAD_ADDR 0x00080000
The patch and rationale seem plausible, but I'm a bit reluctant to apply this this close to 2.0 release, because QEMU has loaded images at this address for 8 years without anybody complaining, and I worry that we might accidentally break some other use case somehow. thanks -- PMM
