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From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Mon, 9 Jul 2018 13:20:43 +0100
Subject: drm/i915: Provide a timeout to i915_gem_wait_for_idle() on setup
Git-commit: 2621cefaa42b3a7455d30e78831c6b55290d40c8
Patch-mainline: v4.19-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

With a broken GPU we expect it to fail during the initial
GPU setup where do a couple of context switches to record the defaults.
This is a task that takes a few milliseconds even on the slowest of
devices, but we may have to wait 60s for hangcheck to give in and
declare the machine inoperable. In this a case where any gpu hang is
unacceptable, both from a timeliness and practical standpoint.

We can therefore set a timeout on our wait-for-idle that is shorter than
the hangcheck (which may be up to 60s for a declaring a wedged driver)
and so detect the broken GPU much more quickly during driver load (and
so prevent stalling userspace for ages).

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180709122044.7028-2-chris@chris-wilson.co.uk

Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/i915/i915_gem.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -5369,11 +5369,11 @@ static int __intel_engines_record_defaul
 	if (err)
 		goto err_active;
 
-	err = i915_gem_wait_for_idle(i915,
-				     I915_WAIT_LOCKED,
-				     MAX_SCHEDULE_TIMEOUT);
-	if (err)
+	if (i915_gem_wait_for_idle(i915, I915_WAIT_LOCKED, HZ / 5)) {
+		i915_gem_set_wedged(i915);
+		err = -EIO; /* Caller will declare us wedged */
 		goto err_active;
+	}
 
 	assert_kernel_context_is_current(i915);