On 23.03.21 12:06, Andy Shevchenko wrote:
On Mon, Mar 22, 2021 at 05:01:58PM +0100, David Hildenbrand wrote:It used to be true that we can have busy system RAM only on the first level in the resourc tree. However, this is no longer holds for driver-managed system RAM (i.e., added via dax/kmem and virtio-mem), which gets added on lower levels. We have two users of walk_system_ram_res(), which currently only consideres the first level: a) kernel/kexec_file.c:kexec_walk_resources() -- We properly skip IORESOURCE_SYSRAM_DRIVER_MANAGED resources via locate_mem_hole_callback(), so even after this change, we won't be placing kexec images onto dax/kmem and virtio-mem added memory. No change. b) arch/x86/kernel/crash.c:fill_up_crash_elf_data() -- we're currently not adding relevant ranges to the crash elf info, resulting in them not getting dumped via kdump. This change fixes loading a crashkernel via kexec_file_load() and including"...fixes..." effectively means to me that Fixes tag should be provided.
We can certainly add, although it doesn't really affect the running kernel, but only crashdumps taken in the kdump kernel:
Fixes: ebf71552bb0e ("virtio-mem: Add parent resource for all added "System RAM"") Fixes: c221c0b0308f ("device-dax: "Hotplug" persistent memory for use like normal RAM")
Thanks -- Thanks, David / dhildenb
