From 3e31af7c468b99fac55c7b76b8585d247da301c5 Mon Sep 17 00:00:00 2001 From: Nirmoy Das Date: Mon, 19 Feb 2024 13:50:47 +0100 Subject: [PATCH] drm/i915: Check before removing mm notifier commit 01bb1ae35006e473138c90711bad1a6b614a1823 upstream. 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: # v5.13+ [tursulin: Added Fixes and cc stable.] Cc: Andi Shyti Cc: Shawn Lee Signed-off-by: Nirmoy Das Reviewed-by: Rodrigo Vivi Link: https://patchwork.freedesktop.org/patch/msgid/20240219125047.28906-1-nirmoy.das@intel.com Signed-off-by: Tvrtko Ursulin (cherry picked from commit db7bbd13f08774cde0332c705f042e327fe21e73) Signed-off-by: Joonas Lahtinen Signed-off-by: Greg Kroah-Hartman --- 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 8ea0fa665e53..1eb2395ea206 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c @@ -374,6 +374,9 @@ 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; }