Re: [PATCHv3 2/2] x86/vdso: Add build salt to the vDSO

[Laura Abbott]

On 05/23/2018 05:06 PM, Linus Torvalds wrote:
> On Wed, May 23, 2018, 17:01 Andy Lutomirski <luto@xxxxxxxxxxxxxx <mailto:luto@xxxxxxxxxxxxxx>> wrote:
>
>
>     I donât know whether Iâm missing something obvious, but canât this be in C?
>
>
> Yes, but I thought Laura wanted to limit it to linker file tricks (this thread has gone on for so long that I've forgotten the details of why).
>
>  Â Â Â ÂLinus

So we have to update the kernel and every module and the easiest way
to do that was the linker script. I was assuming I'd just use the
same approach for the vDSO but you're right that there's no reason
we can't apply a different technique. I notice there's already a
vdso-note.S which adds LINUX_VERSION_CODE as a note. This doesn't
include the extra version so it doesn't quite meet our needs.
There's no reason why we can't throw something else in there for
good measure.

Thanks,
Laura