Comment # 50 on bug 1209436 from John Serock

I was able to reproduce the hang on a Lenovo Thinkpad T520 with an Intel Core
i5-2520M CPU @ 2.50GHz (Intel HD Graphics 3000) by building the .49 kernel from
the https://github.com/openSUSE/kernel/tree/SLE15-SP4 tree, since the .49
kernel was retracted. This shows the last commit from March 14:


john@laptop15:~/git/kernel> git -P log -1
commit 4909d30a5b78240d282801fd2fb84a32f59f9e8a (HEAD -> SLE15-SP4,
origin/SLE15-SP4)
Author: Tony Jones <tonyj@suse.de>
Date:   Tue Mar 14 12:17:28 2023 -0700

    perf/x86/uncore: Don't WARN_ON_ONCE() for a broken discovery
    table (bsc#1206824, bsc#1206493, bsc#1206492).

    suse-commit: 23fd14b823e378dfb3e61305633ee67c17881afa


I was able to fix the issue by applying patch #1 that I mentioned in #c34. This
shows the one-line change to intel_ring.c:


john@laptop15:~/git/kernel> git -P diff
diff --git a/drivers/gpu/drm/i915/gt/intel_ring.c
b/drivers/gpu/drm/i915/gt/intel_ring.c
index 6499f8ba953a..64e494357882 100644
--- a/drivers/gpu/drm/i915/gt/intel_ring.c
+++ b/drivers/gpu/drm/i915/gt/intel_ring.c
@@ -113,7 +113,7 @@ static struct i915_vma *create_ring_vma(struct i915_ggtt
*ggtt, int size)
     struct i915_vma *vma;

     obj = i915_gem_object_create_lmem(i915, size, I915_BO_ALLOC_VOLATILE);
-    if (IS_ERR(obj) && i915_ggtt_has_aperture(ggtt))
+    if (IS_ERR(obj) && i915_ggtt_has_aperture(ggtt) && !HAS_LLC(i915))
         obj = i915_gem_object_create_stolen(i915, size);
     if (IS_ERR(obj))
         obj = i915_gem_object_create_internal(i915, size);
diff --git a/scripts/pahole-flags.sh b/scripts/pahole-flags.sh
old mode 100644
new mode 100755


This just shows that I'm running the newly built kernel:


john@laptop15:~> uname -srv
Linux 5.14.21-150400.24.49-default+ #2 SMP PREEMPT_DYNAMIC Mon Mar 20 07:51:18
EDT 2023