On Fri, 6 Sep 2024 11:07:11 +0800 Huang Ying <ying.huang@xxxxxxxxx> wrote: > On a system with CXL memory, the resource tree (/proc/iomem) related > to CXL memory may look like something as follows. > > 490000000-50fffffff : CXL Window 0 > 490000000-50fffffff : region0 > 490000000-50fffffff : dax0.0 > 490000000-50fffffff : System RAM (kmem) > > Because drivers/dax/kmem.c calls add_memory_driver_managed() during > onlining CXL memory, which makes "System RAM (kmem)" a descendant of > "CXL Window X". This confuses region_intersects(), which expects all > "System RAM" resources to be at the top level of iomem_resource. This > can lead to bugs. > > ... > > Fixes: c221c0b0308f ("device-dax: "Hotplug" persistent memory for use like normal RAM") Do you believe this should be fixed in earlier (-stable) kernels?