We are making calls to C code (e.g. xen_prepare_pvh()) which may use stack canary (stored in GS segment). Signed-off-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx --- arch/x86/xen/xen-pvh.S | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/x86/xen/xen-pvh.S b/arch/x86/xen/xen-pvh.S index 373fef0..4eed586 100644 --- a/arch/x86/xen/xen-pvh.S +++ b/arch/x86/xen/xen-pvh.S @@ -54,6 +54,9 @@ * charge of setting up it's own stack, GDT and IDT. */ +#define PVH_GDT_ENTRY_CANARY 4 +#define PVH_CANARY_SEL (PVH_GDT_ENTRY_CANARY * 8) + ENTRY(pvh_start_xen) cld @@ -64,6 +67,9 @@ ENTRY(pvh_start_xen) mov %eax,%es mov %eax,%ss + mov $(PVH_CANARY_SEL),%eax + mov %eax,%gs + /* Stash hvm_start_info. */ mov $_pa(pvh_start_info), %edi mov %ebx, %esi @@ -150,6 +156,7 @@ gdt_start: .quad 0x00cf9a000000ffff /* __BOOT_CS */ #endif .quad 0x00cf92000000ffff /* __BOOT_DS */ + .quad 0x0040900000000018 /* PVH_CANARY_SEL */ gdt_end: .balign 4 -- 2.9.3
