On Wed, Oct 03, 2018 at 02:34:02PM +0200, Peter Zijlstra wrote: > > Subject: ACPI/NUMA: Fix KASLR build error > > There is no point in trying to compile KASLR specific code when there is > no KASLR. > > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> > --- Yeah, Peter and I were just talking on IRC and he gave me a much better idea how to fix this, see below. I'll run this through the *config builder and commit it if no complaints. --- From: "Peter Zijlstra (Intel)" <peterz@xxxxxxxxxxxxx> Date: Wed, 3 Oct 2018 14:41:27 +0200 Subject: [PATCH] ACPI/NUMA: Fix KASLR build error There is no point in trying to compile KASLR specific code when there is no KASLR. [ bp: Move the whole crap into kaslr.c and make rand_mem_physical_padding static. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Cc: <m.mizuma@xxxxxxxxxxxxxx> Cc: <bhe@xxxxxxxxxx> Cc: <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: <tglx@xxxxxxxxxxxxx> Cc: <mingo@xxxxxxxxxx> Cc: <hpa@xxxxxxxxx> Link: http://lkml.kernel.org/r/20181003123402.GA15494@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx --- arch/x86/include/asm/kaslr.h | 2 ++ arch/x86/include/asm/setup.h | 2 -- arch/x86/mm/kaslr.c | 18 +++++++++++++++++- drivers/acpi/numa.c | 15 +++------------ 4 files changed, 22 insertions(+), 15 deletions(-) diff --git a/arch/x86/include/asm/kaslr.h b/arch/x86/include/asm/kaslr.h index db7ba2feb947..95ef3fc01d12 100644 --- a/arch/x86/include/asm/kaslr.h +++ b/arch/x86/include/asm/kaslr.h @@ -6,8 +6,10 @@ unsigned long kaslr_get_random_long(const char *purpose); #ifdef CONFIG_RANDOMIZE_MEMORY void kernel_randomize_memory(void); +void kaslr_check_padding(void); #else static inline void kernel_randomize_memory(void) { } +static inline void kaslr_check_padding(void) { } #endif /* CONFIG_RANDOMIZE_MEMORY */ #endif diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h index 65a5bf8f6aba..ae13bc974416 100644 --- a/arch/x86/include/asm/setup.h +++ b/arch/x86/include/asm/setup.h @@ -80,8 +80,6 @@ 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/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index 00cf4cae38f5..d58b7da0d55c 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -40,7 +40,7 @@ */ static const unsigned long vaddr_end = CPU_ENTRY_AREA_BASE; -int __initdata rand_mem_physical_padding = CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING; +static int __initdata rand_mem_physical_padding = CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING; /* * Memory regions randomized by KASLR (except modules that use a separate logic * earlier during boot). The list is ordered based on virtual addresses. This @@ -70,6 +70,22 @@ static inline bool kaslr_memory_enabled(void) return kaslr_enabled() && !IS_ENABLED(CONFIG_KASAN); } +/* + * Check the padding size for KASLR is enough. + */ +void kaslr_check_padding(void) +{ + u64 max_possible_phys, max_actual_phys, threshold; + + 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); +} + static int __init rand_mem_physical_padding_setup(char *str) { int max_padding = (1 << (MAX_PHYSMEM_BITS - TB_SHIFT)) - 1; diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c index 3d69834c692f..4408e37600ef 100644 --- a/drivers/acpi/numa.c +++ b/drivers/acpi/numa.c @@ -32,7 +32,7 @@ #include <linux/numa.h> #include <linux/nodemask.h> #include <linux/topology.h> -#include <asm/setup.h> +#include <asm/kaslr.h> static nodemask_t nodes_found_map = NODE_MASK_NONE; @@ -436,7 +436,6 @@ 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; @@ -466,17 +465,9 @@ 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 (parsed_numa_memblks) + kaslr_check_padding(); - 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 */ -- 2.19.0.271.gfe8321ec057f -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.