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Sampat" wrote: > >> >> >> On 1/12/26 3:04 PM, Andrew Morton wrote: >>> On Mon, 12 Jan 2026 14:22:59 -0600 "Pratik R. Sampat" wrote: >>> >>>> Confidential computing guests require memory to be accepted before use. >>>> The unaccepted memory bitmap maintained by firmware does not track >>>> hotplugged memory ranges. >>>> >>>> Call arch_accept_memory() during the hot-add path to explicitly validate >>>> and transition the newly added memory to a private state, making it >>>> usable by the guest. >>>> >>>> Signed-off-by: Pratik R. Sampat >>>> --- >>>> mm/memory_hotplug.c | 4 ++++ >>>> 1 file changed, 4 insertions(+) >>>> >>>> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c >>>> index a63ec679d861..8cfbf0541430 100644 >>>> --- a/mm/memory_hotplug.c >>>> +++ b/mm/memory_hotplug.c >>>> @@ -38,6 +38,7 @@ >>>> #include >>>> >>>> #include >>>> +#include >>> >>> This only exists for x86! >> >> Ah, I missed that entirely. Thanks for catching that. >> >> Probably not the best option to have a generic unaccepted_memory.h as well. >> Maybe, I should have arch_[un]accept_memory() definitions within mm.h wrapped >> within CONFIG_UNACCEPTED_MEMORY instead so that its cleaner. > > Something like that. > > The idiomatic Linus way is to use > > #ifndef arch_accept_memory > #define arch_accept_memory ... > #endif > > Lots of prior art here: > > grep -r include/linux "ifndef arch_" > > > Oh, arch_get_idle_state_flags() got it all wrong. > > #ifdef CONFIG_ACPI_PROCESSOR_IDLE > #ifndef arch_get_idle_state_flags > static inline unsigned int arch_get_idle_state_flags(u32 arch_flags) > { > return 0; > } > #endif > #endif /* CONFIG_ACPI_PROCESSOR_IDLE */ > > - shouldn't have needed "ifdef CONFIG_ACPI_PROCESSOR_IDLE" > > - should have appended > > #define arch_get_idle_state_flags arch_get_idle_state_flags > > in case cpp hit the same lines a second time. > Got it. Thanks for clearing that up. I'll make sure to do it this way in the next iteration. --Pratik