4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: David Woodhouse <d...@amazon.co.uk> commit ea08816d5b185ab3d09e95e393f265af54560350 upstream. Convert indirect call in Xen hypercall to use non-speculative sequence, when CONFIG_RETPOLINE is enabled. Signed-off-by: David Woodhouse <d...@amazon.co.uk> Signed-off-by: Thomas Gleixner <t...@linutronix.de> Acked-by: Arjan van de Ven <ar...@linux.intel.com> Acked-by: Ingo Molnar <mi...@kernel.org> Reviewed-by: Juergen Gross <jgr...@suse.com> Cc: gno...@lxorguk.ukuu.org.uk Cc: Rik van Riel <r...@redhat.com> Cc: Andi Kleen <a...@linux.intel.com> Cc: Josh Poimboeuf <jpoim...@redhat.com> Cc: thomas.lenda...@amd.com Cc: Peter Zijlstra <pet...@infradead.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Jiri Kosina <ji...@kernel.org> Cc: Andy Lutomirski <l...@amacapital.net> Cc: Dave Hansen <dave.han...@intel.com> Cc: Kees Cook <keesc...@google.com> Cc: Tim Chen <tim.c.c...@linux.intel.com> Cc: Greg Kroah-Hartman <gre...@linux-foundation.org> Cc: Paul Turner <p...@google.com> Link: https://lkml.kernel.org/r/1515707194-20531-10-git-send-email-d...@amazon.co.uk Signed-off-by: David Woodhouse <d...@amazon.co.uk> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- arch/x86/include/asm/xen/hypercall.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/arch/x86/include/asm/xen/hypercall.h +++ b/arch/x86/include/asm/xen/hypercall.h @@ -44,6 +44,7 @@ #include <asm/page.h> #include <asm/pgtable.h> #include <asm/smap.h> +#include <asm/nospec-branch.h> #include <xen/interface/xen.h> #include <xen/interface/sched.h> @@ -216,9 +217,9 @@ privcmd_call(unsigned call, __HYPERCALL_5ARG(a1, a2, a3, a4, a5); stac(); - asm volatile("call *%[call]" + asm volatile(CALL_NOSPEC : __HYPERCALL_5PARAM - : [call] "a" (&hypercall_page[call]) + : [thunk_target] "a" (&hypercall_page[call]) : __HYPERCALL_CLOBBER5); clac();
