Commit-ID: 3b054ca88c4f4dd5f516a12d4b6d6bd0ae826f41 Gitweb: https://git.kernel.org/tip/3b054ca88c4f4dd5f516a12d4b6d6bd0ae826f41 Author: Masayoshi Mizuma <m.mizuma@xxxxxxxxxxxxxx> AuthorDate: Mon, 1 Oct 2018 10:08:42 -0400 Committer: Ingo Molnar <mingo@xxxxxxxxxx> CommitDate: Tue, 2 Oct 2018 11:47:21 +0200 ACPI/NUMA: Add warning message if the padding size for KASLR is not enough Add warning message if the padding size for KASLR, rand_mem_physical_padding, is not enough. The message also says the suitable padding size. Signed-off-by: Masayoshi Mizuma <m.mizuma@xxxxxxxxxxxxxx> Cc: Baoquan He <bhe@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Masayoshi Mizuma <msys.mizuma@xxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/20181001140843.26137-3-msys.mizuma@xxxxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> --- arch/x86/include/asm/setup.h | 2 ++ drivers/acpi/numa.c | 14 ++++++++++++++ 2 files changed, 16 insertions(+) diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h index ae13bc974416..65a5bf8f6aba 100644 --- a/arch/x86/include/asm/setup.h +++ b/arch/x86/include/asm/setup.h @@ -80,6 +80,8 @@ static inline unsigned long kaslr_offset(void) return (unsigned long)&_text - __START_KERNEL; } +extern int rand_mem_physical_padding; + /* * Do NOT EVER look at the BIOS memory size location. * It does not work on many machines. diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c index 85167603b9c9..3d69834c692f 100644 --- a/drivers/acpi/numa.c +++ b/drivers/acpi/numa.c @@ -32,6 +32,7 @@ #include <linux/numa.h> #include <linux/nodemask.h> #include <linux/topology.h> +#include <asm/setup.h> static nodemask_t nodes_found_map = NODE_MASK_NONE; @@ -435,6 +436,7 @@ acpi_table_parse_srat(enum acpi_srat_type id, int __init acpi_numa_init(void) { int cnt = 0; + u64 max_possible_phys, max_actual_phys, threshold; if (acpi_disabled) return -EINVAL; @@ -463,6 +465,18 @@ int __init acpi_numa_init(void) cnt = acpi_table_parse_srat(ACPI_SRAT_TYPE_MEMORY_AFFINITY, acpi_parse_memory_affinity, 0); + + /* check the padding size for KASLR is enough. */ + if (parsed_numa_memblks && kaslr_enabled()) { + max_actual_phys = roundup(PFN_PHYS(max_pfn), 1ULL << 40); + max_possible_phys = roundup(PFN_PHYS(max_possible_pfn), 1ULL << 40); + threshold = max_actual_phys + ((u64)rand_mem_physical_padding << 40); + + if (max_possible_phys > threshold) { + pr_warn("Set 'rand_mem_physical_padding=%llu' to avoid memory hotadd failure.\n", + (max_possible_phys - max_actual_phys) >> 40); + } + } } /* SLIT: System Locality Information Table */
![]() |