| From 531bb52a869a9c6e08c8d17ba955fcbfc18037ad Mon Sep 17 00:00:00 2001 |
| From: Peter Zijlstra <peterz@infradead.org> |
| Date: Tue, 23 Jan 2018 16:18:50 +0100 |
| Subject: x86/mm/sme, objtool: Annotate indirect call in sme_encrypt_execute() |
| |
| From: Peter Zijlstra <peterz@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) <peterz@infradead.org> |
| Acked-by: Thomas Gleixner <tglx@linutronix.de> |
| Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> |
| Cc: Andy Lutomirski <luto@kernel.org> |
| Cc: Arjan van de Ven <arjan@linux.intel.com> |
| Cc: Borislav Petkov <bp@alien8.de> |
| Cc: Borislav Petkov <bp@suse.de> |
| Cc: Dan Williams <dan.j.williams@intel.com> |
| Cc: Dave Hansen <dave.hansen@linux.intel.com> |
| Cc: David Woodhouse <dwmw2@infradead.org> |
| Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| Cc: Linus Torvalds <torvalds@linux-foundation.org> |
| Cc: Peter Zijlstra <peterz@infradead.org> |
| Cc: Tom Lendacky <thomas.lendacky@amd.com> |
| Signed-off-by: Ingo Molnar <mingo@kernel.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@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 |
