x86/entry: Cleanup PARAVIRT

Since commit 5c8f6a2e316e ("x86/xen: Add
xenpv_restore_regs_and_return_to_usermode()") Xen will no longer reach
this code and we can do away with the paravirt
SWAPGS/INTERRUPT_RETURN.

Suggested-by: Andrew Cooper <Andrew.Cooper3@citrix.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.756014488@infradead.org

diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 466df3e..22e4e9a 100644 (file)
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -608,8 +608,8 @@ SYM_INNER_LABEL(swapgs_restore_regs_and_return_to_usermode, SYM_L_GLOBAL)
 
        /* Restore RDI. */
        popq    %rdi
-       SWAPGS
-       INTERRUPT_RETURN
+       swapgs
+       jmp     native_iret
 
 
 SYM_INNER_LABEL(restore_regs_and_return_to_kernel, SYM_L_GLOBAL)