[Xenomai] [PATCH] arm/ipipe: Fix logical inversion in ret_from_exception

[Jan Kiszka <jan.kiszka@siemens.com>]

On return from exception, we want to check if the current context is
root or head to take the fast exit in the latter case. TIP_HEAD is set
then, thus we have to check for 'ne' (Z==0) after tst.

This affects only non-legacy users.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---

This is for 3.14, but it should equally well apply to 3.16. Fixes both
sigdebug test as well as the weird sshd deaths on the virtual vexpress
target.

 arch/arm/kernel/entry-armv.S | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index a608340..f6ef839 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -736,8 +736,8 @@ ENTRY(ret_from_exception)
 	get_thread_info tsk
 	ldr	r0, [tsk, #TI_IPIPE]
 	tst	r0, #_TIP_HEAD
- THUMB(	it eq)
-	beq	__ipipe_ret_to_user_irqs_disabled  @ Fast exit path over non-root domains
+ THUMB(	it ne)
+	bne	__ipipe_ret_to_user_irqs_disabled  @ Fast exit path over non-root domains
 #endif /* !CONFIG_IPIPE_LEGACY */
 #else /* !CONFIG_IPIPE */
 	get_thread_info tsk
-- 
2.1.4