Start symbol for an compressed kernel

[Russell King - ARM Linux]

On Sat, Aug 17, 2013 at 10:03:32PM +0800, zhaobin xv wrote:
> 2013/8/17 Russell King - ARM Linux <linux at arm.linux.org.uk>:
> > On Sat, Aug 17, 2013 at 09:56:14PM +0800, zhaobin xv wrote:
> >> 2013/8/17 Russell King - ARM Linux <linux at arm.linux.org.uk>:
> >> > On Sat, Aug 17, 2013 at 07:39:46PM +0800, zhaobin xv wrote:
> >> >> how to find Start symbol for an compressed kernel for arm
> >> >
> >> > The start address of a compressed kernel is the first byte of the image.
> >> >
> >> > Symbolically, that is 'start', which is a non-global symbol.  However,
> >> > this symbol is useless since it normally is zero, because the entire
> >> > image is relocatable and therefore built for address zero.
> >> >
> >> > However, it is normal to load the image not at address zero.
> >>
> >> why do U define ENTRY(_start)?
> >> Is _start the Start symbol?
> >> how to explain _start
> >
> > There is no _start symbol in the compressed kernel.
> 
> But there is ENTRY(_start) and _start in
> linux-2.6.22.6\arch\arm\boot\compressed/head.S

There is no mainline -final kernel with ENTRY(_start) in that file.
I would be really surprised to find that a stable kernel ever introduced
such a thing without it being in a mainline kernel first.  Therefore, I
believe you are mistaken that a vanilla 2.6.22.6 has this.

You may have a modified 2.6.22.6 kernel source there.