x86/paravirt: add sysret/sysexit pvops for returning to 32-bit compatibility userspace
In a 64-bit system, we need separate sysret/sysexit operations to
return to a 32-bit userspace.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citirx.com>
Cc: xen-devel <xen-devel@lists.xensource.com>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index b0b17f0..bf1067e 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -141,7 +141,8 @@
ret = paravirt_patch_nop();
else if (type == PARAVIRT_PATCH(pv_cpu_ops.iret) ||
type == PARAVIRT_PATCH(pv_cpu_ops.irq_enable_sysexit) ||
- type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret))
+ type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret32) ||
+ type == PARAVIRT_PATCH(pv_cpu_ops.usergs_sysret64))
/* If operation requires a jmp, then jmp */
ret = paravirt_patch_jmp(insnbuf, opfunc, addr, len);
else
@@ -193,7 +194,8 @@
/* These are in entry.S */
extern void native_iret(void);
extern void native_irq_enable_sysexit(void);
-extern void native_usergs_sysret(void);
+extern void native_usergs_sysret32(void);
+extern void native_usergs_sysret64(void);
static int __init print_banner(void)
{
@@ -329,10 +331,10 @@
.write_idt_entry = native_write_idt_entry,
.load_sp0 = native_load_sp0,
-#ifdef CONFIG_X86_32
.irq_enable_sysexit = native_irq_enable_sysexit,
-#else
- .usergs_sysret = native_usergs_sysret,
+#ifdef CONFIG_X86_64
+ .usergs_sysret32 = native_usergs_sysret32,
+ .usergs_sysret64 = native_usergs_sysret64,
#endif
.iret = native_iret,
.swapgs = native_swapgs,