CVE-2023-53706 mm/vmemmap/devdax: fix kernel crash when probing devdax devices

In the Linux kernel, the following vulnerability has been resolved: mm/vmemmap/devdax: fix kernel crash when probing devdax devices commit 4917f55b4ef9 "mm/sparse-vmemmap: improve memory savings for compound devmaps" added support for using optimized vmmemap for devdax devices. But how vmemmap...