Re: [PATCH v3 08/23] x86/xen_hello_world.xsplice: Test payload for patching 'xen_extra_version'. (v2)

[Ross Lagerwall <ross.lagerwall@citrix.com>]

On 02/12/2016 06:05 PM, Konrad Rzeszutek Wilk wrote:
> This change demonstrates how to generate an xSplice ELF payload.
>
> The idea here is that we want to patch in the hypervisor
> the 'xen_version_extra' function with an function that will
> return 'Hello World'. The 'xl info | grep extraversion'
> will reflect the new value after the patching.
>
> To generate this ELF payload file we need:
>   - C code of the new code (xen_hello_world_func.c).
>   - C code generating the .xsplice.funcs structure
>     (xen_hello_world.c)
>   - The address of the old code (xen_extra_version). We
>     retrieve it by  using 'nm --defined' on xen-syms.
>   - The size of the new and old code for which we use
>     nm --defined -S on our code and xen-syms respectively.
>
snip
> diff --git a/tools/misc/xsplice.lds b/tools/misc/xsplice.lds
> new file mode 100644
> index 0000000..f52eb8c
> --- /dev/null
> +++ b/tools/misc/xsplice.lds
> @@ -0,0 +1,11 @@
> +OUTPUT_FORMAT("elf64-x86-64", "elf64-x86-64", "elf64-x86-64")
> +OUTPUT_ARCH(i386:x86-64)
> +ENTRY(xsplice_hello_world)
> +SECTIONS
> +{
> +    /* The hypervisor expects ".xsplice.func", so change
> +     * the ".data.xsplice_hello_world" to it. */
> +
> +    .xsplice.funcs : { *(*.xsplice_hello_world) }
> +
> +}

I think this file can be dropped now, nothing uses it as far as I can see.

-- 
Ross Lagerwall