From: Jeremy Fitzhardinge <jeremy@goop.org>
Date: Mon, 17 Mar 2008 23:37:12 +0000 (-0700)
Subject: xen: make sure iret faults are trapped
X-Git-Tag: firefly_0821_release~21542^2~32
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=90e9f53662826db3cdd6d99bd394d727b05160c1;p=firefly-linux-kernel-4.4.55.git

xen: make sure iret faults are trapped

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---

diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index f0f8934fc303..568c6ccd7ae2 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -409,7 +409,7 @@ restore_nocheck_notrace:
 irq_return:
 	INTERRUPT_RETURN
 .section .fixup,"ax"
-iret_exc:
+ENTRY(iret_exc)
 	pushl $0			# no error code
 	pushl $do_iret_error
 	jmp error_code
diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S
index fe161ed4b01e..99223cc323be 100644
--- a/arch/x86/xen/xen-asm.S
+++ b/arch/x86/xen/xen-asm.S
@@ -184,8 +184,12 @@ iret_restore_end:
 	   region is OK. */
 	je xen_hypervisor_callback
 
-	iret
+1:	iret
 xen_iret_end_crit:
+.section __ex_table,"a"
+	.align 4
+	.long 1b,iret_exc
+.previous
 
 hyper_iret:
 	/* put this out of line since its very rarely used */