4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Peter Zijlstra <pet...@infradead.org> commit 531bb52a869a9c6e08c8d17ba955fcbfc18037ad upstream. This is boot code and thus Spectre-safe: we run this _way_ before userspace comes along to have a chance to poison our branch predictor. Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Acked-by: Thomas Gleixner <t...@linutronix.de> Acked-by: Josh Poimboeuf <jpoim...@redhat.com> Cc: Andy Lutomirski <l...@kernel.org> Cc: Arjan van de Ven <ar...@linux.intel.com> Cc: Borislav Petkov <b...@alien8.de> Cc: Borislav Petkov <b...@suse.de> Cc: Dan Williams <dan.j.willi...@intel.com> Cc: Dave Hansen <dave.han...@linux.intel.com> Cc: David Woodhouse <dw...@infradead.org> Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Tom Lendacky <thomas.lenda...@amd.com> Signed-off-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- arch/x86/mm/mem_encrypt_boot.S | 2 ++ 1 file changed, 2 insertions(+) --- a/arch/x86/mm/mem_encrypt_boot.S +++ b/arch/x86/mm/mem_encrypt_boot.S @@ -15,6 +15,7 @@ #include <asm/page.h> #include <asm/processor-flags.h> #include <asm/msr-index.h> +#include <asm/nospec-branch.h> .text .code64 @@ -59,6 +60,7 @@ ENTRY(sme_encrypt_execute) movq %rax, %r8 /* Workarea encryption routine */ addq $PAGE_SIZE, %r8 /* Workarea intermediate copy buffer */ + ANNOTATE_RETPOLINE_SAFE call *%rax /* Call the encryption routine */ pop %r12