Commit b3fefbb3 authored by David Hildenbrand's avatar David Hildenbrand Committed by Danilo Krummrich
Browse files

nouveau/svm: fix missing folio unlock + put after make_device_exclusive_range() 



In case we have to retry the loop, we are missing to unlock+put the
folio. In that case, we will keep failing make_device_exclusive_range()
because we cannot grab the folio lock, and even return from the function
with the folio locked and referenced, effectively never succeeding the
make_device_exclusive_range().

While at it, convert the other unlock+put to use a folio as well.

This was found by code inspection.

Fixes: 8f187163 ("nouveau/svm: implement atomic SVM access")
Signed-off-by: default avatarDavid Hildenbrand <david@redhat.com>
Reviewed-by: default avatarAlistair Popple <apopple@nvidia.com>
Tested-by: default avatarAlistair Popple <apopple@nvidia.com>
Signed-off-by: default avatarDanilo Krummrich <dakr@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20250124181524.3584236-2-david@redhat.com
parent a8972d5a

drivers/gpu/drm/nouveau/nouveau_svm.c

+7 −2
Original line number Diff line number Diff line
@@ -590,6 +590,7 @@ static int nouveau_atomic_range_fault(struct nouveau_svmm *svmm, 
	unsigned long timeout =

		jiffies + msecs_to_jiffies(HMM_RANGE_DEFAULT_TIMEOUT);

	struct mm_struct *mm = svmm->notifier.mm;

	struct folio *folio;

	struct page *page;

	unsigned long start = args->p.addr;

	unsigned long notifier_seq;
@@ -616,12 +617,16 @@ static int nouveau_atomic_range_fault(struct nouveau_svmm *svmm, 
			ret = -EINVAL;

			goto out;

		}

		folio = page_folio(page);



		mutex_lock(&svmm->mutex);

		if (!mmu_interval_read_retry(&notifier->notifier,

					     notifier_seq))

			break;

		mutex_unlock(&svmm->mutex);



		folio_unlock(folio);

		folio_put(folio);

	}



	/* Map the page on the GPU. */
@@ -637,8 +642,8 @@ static int nouveau_atomic_range_fault(struct nouveau_svmm *svmm, 
	ret = nvif_object_ioctl(&svmm->vmm->vmm.object, args, size, NULL);

	mutex_unlock(&svmm->mutex);



	unlock_page(page);

	put_page(page);

	folio_unlock(folio);

	folio_put(folio);



out:

	mmu_interval_notifier_remove(&notifier->notifier);