From: Nicolin Chen nicolinc@nvidia.com Sent: Saturday, June 14, 2025 3:15 PM
+int iommufd_access_notify_unmap(struct io_pagetable *iopt, unsigned long iova,
unsigned long length){ struct iommufd_ioas *ioas = container_of(iopt, struct iommufd_ioas, iopt); struct iommufd_access *access; unsigned long index;
int ret = 0;
xa_lock(&ioas->iopt.access_list); xa_for_each(&ioas->iopt.access_list, index, access) {
if (!access->ops || !access->ops->unmap) {ret = -EBUSY;goto unlock;}
then accesses before this one have been notified to unpin the area while accesses afterwards are left unnotified.
in the end the unmap fails but with some side-effect incurred.
I'm not sure whether this intermediate state may lead to any undesired effect later. Just raise it in case you or Jason already thought about it.
/* Something is not responding to unmap requests.*/ tries++;
if (WARN_ON(tries > 100))return -EDEADLOCK;
if (WARN_ON(tries > 100)) {rc = -EDEADLOCK;goto out_unmapped;}
this looks an unrelated fix?