On Wed, 26 Mar 2025 at 19:34, Mike Rapoport <r...@kernel.org> wrote: > > Hi Dave, > > On Wed, Mar 26, 2025 at 05:17:16PM +0800, Dave Young wrote: > > On Tue, 25 Mar 2025 at 16:36, Dave Young <dyo...@redhat.com> wrote: > > > > > > > > > > > > > Have you tested kdump? In my mind there are two issues, one is with > > > > > CMA enabled, it could cause kdump crashkernel memory reservation > > > > > failures more often due to the fragmented low memory. Secondly, in > > > > > > > > kho scracth memorys are reserved much later than crashkernel, we may not > > > > need to worry about it. > > > > ==================== > > > > start_kernel() > > > > ...... > > > > -->setup_arch(&command_line); > > > > -->arch_reserve_crashkernel(); > > > > ...... > > > > -->mm_core_init(); > > > > -->kho_memory_init(); > > > > > > > > > kdump kernel dump the crazy scratch memory in vmcore is not very > > > > > meaningful. Otherwise I suspect this is not tested under kdump. If > > > > > so please disable this option for kdump. > > > > > > Ok, it is fine if this is the case, thanks Baoquan for clearing this > > > worry. > > > > > > But the other concerns are still need to address, eg. KHO use cases > > > are not good for kdump. > > > There could be more to think about. > > > eg. the issues talked in thread: > > > https://lore.kernel.org/lkml/z7dc9cd8kx3b_...@dwarf.suse.cz/T/ > > > > Rethink about this, other than previous concerns. Transferring the > > old kernel state to kdump kernel makes no sense since the old state is > > not stable as the kernel has crashed. > > KHO won't be active for kdump case. The KHO segments are only added to > kexec_image and never to kexec_crash_image.
Good to know, thanks! > > -- > Sincerely yours, > Mike. >
