4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Borislav Petkov <b...@suse.de> commit 337e4cc84021212a87b04b77b65cccc49304909e upstream Add .altinstr_aux for additional instructions which will be used before and/or during patching. All stuff which needs more sophisticated patching should go there. See next patch. Signed-off-by: Borislav Petkov <b...@suse.de> Cc: Andy Lutomirski <l...@amacapital.net> Cc: Borislav Petkov <b...@alien8.de> Cc: Brian Gerst <brge...@gmail.com> Cc: Denys Vlasenko <dvlas...@redhat.com> Cc: H. Peter Anvin <h...@zytor.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Link: http://lkml.kernel.org/r/1453842730-28463-8-git-send-email...@alien8.de Signed-off-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Srivatsa S. Bhat <sriva...@csail.mit.edu> Reviewed-by: Matt Helsley (VMware) <matt.hels...@gmail.com> Reviewed-by: Alexey Makhalov <amakha...@vmware.com> Reviewed-by: Bo Gan <g...@vmware.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- arch/x86/kernel/vmlinux.lds.S | 11 +++++++++++ 1 file changed, 11 insertions(+) --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -202,6 +202,17 @@ SECTIONS :init #endif + /* + * Section for code used exclusively before alternatives are run. All + * references to such code must be patched out by alternatives, normally + * by using X86_FEATURE_ALWAYS CPU feature bit. + * + * See static_cpu_has() for an example. + */ + .altinstr_aux : AT(ADDR(.altinstr_aux) - LOAD_OFFSET) { + *(.altinstr_aux) + } + INIT_DATA_SECTION(16) .x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) {
