[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH v2 06/27] x86/entry/64: Adapt assembly for PIE support



On Tue, Mar 13, 2018 at 01:59:24PM -0700, Thomas Garnier wrote:
> @@ -1576,7 +1578,9 @@ first_nmi:
>       addq    $8, (%rsp)      /* Fix up RSP */
>       pushfq                  /* RFLAGS */
>       pushq   $__KERNEL_CS    /* CS */
> -     pushq   $1f             /* RIP */
> +     pushq   %rax            /* Support Position Independent Code */
> +     leaq    1f(%rip), %rax  /* RIP */
> +     xchgq   %rax, (%rsp)    /* Restore RAX, put 1f */
>       iretq                   /* continues at repeat_nmi below */
>       UNWIND_HINT_IRET_REGS
>  1:

Urgh, xchg with a memop has an implicit LOCK prefix.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.