From: Ben Hutchings ben@decadent.org.uk
The hypercall_page is special and the RETs there should not be changed into rethunk calls (but can have SLS mitigation). Change the initial instructions to ret + int3 padding, as was done in upstream commit 5b2fc51576ef "x86/ibt,xen: Sprinkle the ENDBR".
Signed-off-by: Ben Hutchings ben@decadent.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/xen/xen-head.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/arch/x86/xen/xen-head.S +++ b/arch/x86/xen/xen-head.S @@ -69,9 +69,9 @@ SYM_CODE_END(asm_cpu_bringup_and_idle) SYM_CODE_START(hypercall_page) .rept (PAGE_SIZE / 32) UNWIND_HINT_FUNC - .skip 31, 0x90 ANNOTATE_UNRET_SAFE - RET + ret + .skip 31, 0xcc .endr
#define HYPERCALL(n) \