This moves memory notifier registration earlier in the boot process from device_initcall() to early_initcall() which will help in guarding against potential early boot memory offline requests. Even though there should not be any actual offlinig requests till memory block devices are initialized with memory_dev_init() but then generic init sequence might just change in future. Hence an early registration for the memory event notifier would be helpful. While here, just skip the registration if CONFIG_MEMORY_HOTREMOVE is not enabled and also call out when memory notifier registration fails.
Cc: Catalin Marinas <[email protected]> Cc: Will Deacon <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Marc Zyngier <[email protected]> Cc: Steve Capper <[email protected]> Cc: Mark Brown <[email protected]> Cc: [email protected] Cc: [email protected] Reviewed-by: Gavin Shan <[email protected]> Reviewed-by: Catalin Marinas <[email protected]> Signed-off-by: Anshuman Khandual <[email protected]> --- arch/arm64/mm/mmu.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 1c0f3e02f731..71dd9d753b8b 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -1510,7 +1510,16 @@ static struct notifier_block prevent_bootmem_remove_nb = { static int __init prevent_bootmem_remove_init(void) { - return register_memory_notifier(&prevent_bootmem_remove_nb); + int ret = 0; + + if (!IS_ENABLED(CONFIG_MEMORY_HOTREMOVE)) + return ret; + + ret = register_memory_notifier(&prevent_bootmem_remove_nb); + if (ret) + pr_err("%s: Notifier registration failed %d\n", __func__, ret); + + return ret; } -device_initcall(prevent_bootmem_remove_init); +early_initcall(prevent_bootmem_remove_init); #endif -- 2.20.1
