From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Date: Thu, 15 Feb 2018 10:14:25 +0100
Subject: drm/i915: Release connector iterator on a digital port conflict.
Git-commit: bd67a8c15a3b59ea9b21aee31e867c728661977d
Patch-mainline: v4.17-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166
Hitting the failure path through check_digital_port_conflicts triggers:
================================================
WARNING: lock held when returning to user space!
4.16.0-rc1-CI-kasan_1+ #1 Tainted: G W
------------------------------------------------
kms_3d/1439 is leaving the kernel with locks still held!
1 lock held by kms_3d/1439:
#0: (drm_connector_list_iter){.+.+}, at: [<000000003745d183>] intel_atomic_check+0x1d9d/0x3ff0 [i915]
Rearrange the code to have a single exit path through the unlock.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180215091425.42364-1-maarten.lankhorst@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
drivers/gpu/drm/i915/intel_display.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -10721,6 +10721,7 @@ static bool check_digital_port_conflicts
struct drm_connector_list_iter conn_iter;
unsigned int used_ports = 0;
unsigned int used_mst_ports = 0;
+ bool ret = true;
/*
* Walk the connector list instead of the encoder
@@ -10755,7 +10756,7 @@ static bool check_digital_port_conflicts
/* the same port mustn't appear more than once */
if (used_ports & port_mask)
- return false;
+ ret = false;
used_ports |= port_mask;
break;
@@ -10773,7 +10774,7 @@ static bool check_digital_port_conflicts
if (used_ports & used_mst_ports)
return false;
- return true;
+ return ret;
}
static void