x86/xen: Fix initialisation in hypercall_page after rethunk

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>
This commit is contained in:
Ben Hutchings 2022-07-14 00:39:33 +02:00 committed by Greg Kroah-Hartman
parent 81f20e5000
commit 668cb1ddf0

View File

@ -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) \