From: Muchun Song <songmuchun@xxxxxxxxxxxxx> Subject: mm: memory_hotplug: disable memmap_on_memory when hugetlb_free_vmemmap enabled The parameter of memory_hotplug.memmap_on_memory is not compatible with hugetlb_free_vmemmap. So disable it when hugetlb_free_vmemmap is enabled. [akpm@xxxxxxxxxxxxxxxxxxxx: remove unneeded include, per Oscar] Link: https://lkml.kernel.org/r/20210510030027.56044-9-songmuchun@xxxxxxxxxxxxx Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> Acked-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx> Cc: Balbir Singh <bsingharora@xxxxxxxxx> Cc: Barry Song <song.bao.hua@xxxxxxxxxxxxx> Cc: Bodeddula Balasubramaniam <bodeddub@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Chen Huang <chenhuang5@xxxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: HORIGUCHI NAOYA <naoya.horiguchi@xxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Joao Martins <joao.m.martins@xxxxxxxxxx> Cc: Joerg Roedel <jroedel@xxxxxxx> Cc: Jonathan Corbet <corbet@xxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Miaohe Lin <linmiaohe@xxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Mina Almasry <almasrymina@xxxxxxxxxx> Cc: Oliver Neukum <oneukum@xxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Cc: Paul E. McKenney <paulmck@xxxxxxxxxx> Cc: Pawan Gupta <pawan.kumar.gupta@xxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Xiongchun Duan <duanxiongchun@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- Documentation/admin-guide/kernel-parameters.txt | 8 ++++++++ mm/memory_hotplug.c | 1 + 2 files changed, 9 insertions(+) --- a/Documentation/admin-guide/kernel-parameters.txt~mm-memory_hotplug-disable-memmap_on_memory-when-hugetlb_free_vmemmap-enabled +++ a/Documentation/admin-guide/kernel-parameters.txt @@ -1584,6 +1584,10 @@ on: enable the feature off: disable the feature + This is not compatible with memory_hotplug.memmap_on_memory. + If both parameters are enabled, hugetlb_free_vmemmap takes + precedence over memory_hotplug.memmap_on_memory. + hung_task_panic= [KNL] Should the hung task detector generate panics. Format: 0 | 1 @@ -2850,6 +2854,10 @@ Note that even when enabled, there are a few cases where the feature is not effective. + This is not compatible with hugetlb_free_vmemmap. If + both parameters are enabled, hugetlb_free_vmemmap takes + precedence over memory_hotplug.memmap_on_memory. + memtest= [KNL,X86,ARM,PPC,RISCV] Enable memtest Format: <integer> default : 0 <disable> --- a/mm/memory_hotplug.c~mm-memory_hotplug-disable-memmap_on_memory-when-hugetlb_free_vmemmap-enabled +++ a/mm/memory_hotplug.c @@ -1056,6 +1056,7 @@ bool mhp_supports_memmap_on_memory(unsig * populate a single PMD. */ return memmap_on_memory && + !is_hugetlb_free_vmemmap_enabled() && IS_ENABLED(CONFIG_MHP_MEMMAP_ON_MEMORY) && size == memory_block_size_bytes() && IS_ALIGNED(vmemmap_size, PMD_SIZE) && _
