diff options
Diffstat (limited to 'arch/x86/xen/xen-asm_64.S')
| -rw-r--r-- | arch/x86/xen/xen-asm_64.S | 61 |
1 files changed, 32 insertions, 29 deletions
diff --git a/arch/x86/xen/xen-asm_64.S b/arch/x86/xen/xen-asm_64.S index c3df43141e70..3a3b6a211584 100644 --- a/arch/x86/xen/xen-asm_64.S +++ b/arch/x86/xen/xen-asm_64.S @@ -1,14 +1,8 @@ /* - * Asm versions of Xen pv-ops, suitable for either direct use or - * inlining. The inline versions are the same as the direct-use - * versions, with the pre- and post-amble chopped off. - * - * This code is encoded for size rather than absolute efficiency, with - * a view to being able to inline as much as possible. + * Asm versions of Xen pv-ops, suitable for direct use. * * We only bother with direct forms (ie, vcpu in pda) of the - * operations here; the indirect forms are better handled in C, since - * they're generally too large to inline anyway. + * operations here; the indirect forms are better handled in C. */ #include <asm/errno.h> @@ -20,7 +14,7 @@ #include <xen/interface/xen.h> -#include "xen-asm.h" +#include <linux/linkage.h> ENTRY(xen_adjust_exception_frame) mov 8+0(%rsp), %rcx @@ -46,9 +40,7 @@ hypercall_iret = hypercall_page + __HYPERVISOR_iret * 32 */ ENTRY(xen_iret) pushq $0 -1: jmp hypercall_iret -ENDPATCH(xen_iret) -RELOC(xen_iret, 1b+1) + jmp hypercall_iret ENTRY(xen_sysret64) /* @@ -65,9 +57,7 @@ ENTRY(xen_sysret64) pushq %rcx pushq $VGCF_in_syscall -1: jmp hypercall_iret -ENDPATCH(xen_sysret64) -RELOC(xen_sysret64, 1b+1) + jmp hypercall_iret /* * Xen handles syscall callbacks much like ordinary exceptions, which @@ -82,34 +72,47 @@ RELOC(xen_sysret64, 1b+1) * rip * r11 * rsp->rcx - * - * In all the entrypoints, we undo all that to make it look like a - * CPU-generated syscall/sysenter and jump to the normal entrypoint. */ -.macro undo_xen_syscall - mov 0*8(%rsp), %rcx - mov 1*8(%rsp), %r11 - mov 5*8(%rsp), %rsp -.endm - /* Normal 64-bit system call target */ ENTRY(xen_syscall_target) - undo_xen_syscall - jmp entry_SYSCALL_64_after_swapgs + popq %rcx + popq %r11 + + /* + * Neither Xen nor the kernel really knows what the old SS and + * CS were. The kernel expects __USER_DS and __USER_CS, so + * report those values even though Xen will guess its own values. + */ + movq $__USER_DS, 4*8(%rsp) + movq $__USER_CS, 1*8(%rsp) + + jmp entry_SYSCALL_64_after_hwframe ENDPROC(xen_syscall_target) #ifdef CONFIG_IA32_EMULATION /* 32-bit compat syscall target */ ENTRY(xen_syscall32_target) - undo_xen_syscall - jmp entry_SYSCALL_compat + popq %rcx + popq %r11 + + /* + * Neither Xen nor the kernel really knows what the old SS and + * CS were. The kernel expects __USER32_DS and __USER32_CS, so + * report those values even though Xen will guess its own values. + */ + movq $__USER32_DS, 4*8(%rsp) + movq $__USER32_CS, 1*8(%rsp) + + jmp entry_SYSCALL_compat_after_hwframe ENDPROC(xen_syscall32_target) /* 32-bit compat sysenter target */ ENTRY(xen_sysenter_target) - undo_xen_syscall + mov 0*8(%rsp), %rcx + mov 1*8(%rsp), %r11 + mov 5*8(%rsp), %rsp jmp entry_SYSENTER_compat ENDPROC(xen_sysenter_target) |