The parameter of memory_hotplug.memmap_on_memory is not compatible with hugetlb_free_vmemmap. So disable it when hugetlb_free_vmemmap is enabled.
Signed-off-by: Muchun Song <[email protected]> --- Documentation/admin-guide/kernel-parameters.txt | 4 ++++ drivers/acpi/acpi_memhotplug.c | 1 + mm/memory_hotplug.c | 18 +++++++++++++----- 3 files changed, 18 insertions(+), 5 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 9e655f5206ac..1f648b3e6120 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2893,6 +2893,10 @@ 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> diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c index 8cc195c4c861..0d7f595ee441 100644 --- a/drivers/acpi/acpi_memhotplug.c +++ b/drivers/acpi/acpi_memhotplug.c @@ -15,6 +15,7 @@ #include <linux/acpi.h> #include <linux/memory.h> #include <linux/memory_hotplug.h> +#include <linux/hugetlb.h> #include "internal.h" diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 68923c19bdea..c45ed6c0cd9f 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -981,6 +981,7 @@ static int online_memory_block(struct memory_block *mem, void *arg) bool mhp_supports_memmap_on_memory(unsigned long size) { + bool supported; unsigned long nr_vmemmap_pages = size / PAGE_SIZE; unsigned long vmemmap_size = nr_vmemmap_pages * sizeof(struct page); unsigned long remaining_size = size - vmemmap_size; @@ -1011,11 +1012,18 @@ bool mhp_supports_memmap_on_memory(unsigned long size) * altmap as an alternative source of memory, and we do not exactly * populate a single PMD. */ - return memmap_on_memory && - IS_ENABLED(CONFIG_MHP_MEMMAP_ON_MEMORY) && - size == memory_block_size_bytes() && - IS_ALIGNED(vmemmap_size, PMD_SIZE) && - IS_ALIGNED(remaining_size, pageblock_nr_pages << PAGE_SHIFT); + supported = memmap_on_memory && + IS_ENABLED(CONFIG_MHP_MEMMAP_ON_MEMORY) && + size == memory_block_size_bytes() && + IS_ALIGNED(vmemmap_size, PMD_SIZE) && + IS_ALIGNED(remaining_size, pageblock_nr_pages << PAGE_SHIFT); + + if (supported && is_hugetlb_free_vmemmap_enabled()) { + pr_info("Cannot enable memory_hotplug.memmap_on_memory, it is not compatible with hugetlb_free_vmemmap\n"); + supported = false; + } + + return supported; } /* -- 2.11.0
