The patch below does not apply to the 6.8-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
>From db7bbd13f08774cde0332c705f042e327fe21e73 Mon Sep 17 00:00:00 2001
From: Nirmoy Das <nirmoy.das@xxxxxxxxx>
Date: Mon, 19 Feb 2024 13:50:47 +0100
Subject: [PATCH] drm/i915: Check before removing mm notifier
Error in mmu_interval_notifier_insert() can leave a NULL
notifier.mm pointer. Catch that and return early.
Fixes: ed29c2691188 ("drm/i915: Fix userptr so we do not have to worry about obj->mm.lock, v7.")
Cc: <stable@xxxxxxxxxxxxxxx> # v5.13+
[tursulin: Added Fixes and cc stable.]
Cc: Andi Shyti <andi.shyti@xxxxxxxxxxxxxxx>
Cc: Shawn Lee <shawn.c.lee@xxxxxxxxx>
Signed-off-by: Nirmoy Das <nirmoy.das@xxxxxxxxx>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20240219125047.28906-1-nirmoy.das@xxxxxxxxx
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
---
drivers/gpu/drm/i915/gem/i915_gem_userptr.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
index 0e21ce9d3e5ac..61abfb505766d 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c
@@ -349,6 +349,9 @@ i915_gem_userptr_release(struct drm_i915_gem_object *obj)
{
GEM_WARN_ON(obj->userptr.page_ref);
+ if (!obj->userptr.notifier.mm)
+ return;
+
mmu_interval_notifier_remove(&obj->userptr.notifier);
obj->userptr.notifier.mm = NULL;
}
--
2.43.0
