>> Now, let's clarify what I want regarding virtio-mem: >> >> 1. kexec should not add virtio-mem memory to the initial firmware >> memmap. The driver has to be in charge as discussed. >> 2. kexec should not place kexec images onto virtio-mem memory. That >> would end badly. >> 3. kexec should still dump virtio-mem memory via kdump. > > Ok, but then seems to say to me that dax/kmem is a different type of > (driver managed) than virtio-mem and it's confusing to try to apply > the same meaning. Why not just call your type for the distinct type it > is "System RAM (virtio-mem)" and let any other driver managed memory > follow the same "System RAM ($driver)" format if it wants? I had the same idea but discarded it because it seemed to uglify the add_memory() interface (passing yet another parameter only relevant for driver managed memory). Maybe we really want a new one, because I like that idea: /* * Add special, driver-managed memory to the system as system ram. * The resource_name is expected to have the name format "System RAM * ($DRIVER)", so user space (esp. kexec-tools)" can special-case it. * * For this memory, no entries in /sys/firmware/memmap are created, * as this memory won't be part of the raw firmware-provided memory map * e.g., after a reboot. Also, the created memory resource is flagged * with IORESOURCE_MEM_DRIVER_MANAGED, so in-kernel users can special- * case this memory (e.g., not place kexec images onto it). */ int add_memory_driver_managed(int nid, u64 start, u64 size, const char *resource_name); If we'd ever have to special case it even more in the kernel, we could allow to specify further resource flags. While passing the driver name instead of the resource_name would be an option, this way we don't have to hand craft new resource strings for added memory resources. Thoughts? -- Thanks, David / dhildenb
