x86/xen: Avoid relocatable quantities in Xen ELF notes

Xen puts virtual and physical addresses into ELF notes that are treated
by the linker as relocatable by default. Doing so is not only pointless,
given that the ELF notes are only intended for consumption by Xen before
the kernel boots. It is also a KASLR leak, given that the kernel's ELF
notes are exposed via the world readable /sys/kernel/notes.

So emit these constants in a way that prevents the linker from marking
them as relocatable. This involves place-relative relocations (which
subtract their own virtual address from the symbol value) and linker
provided absolute symbols that add the address of the place to the
desired value.

Tested-by: Jason Andryuk <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>
Reviewed-by: Jason Andryuk <[email protected]>
Message-ID: <[email protected]>
Signed-off-by: Juergen Gross <[email protected]>

0 files changed, 0 insertions, 0 deletions