diff options
Diffstat (limited to 'arch/x86/mm/init.c')
| -rw-r--r-- | arch/x86/mm/init.c | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index e26f5c5c6565..dd694fb93916 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -157,16 +157,25 @@ __ref void *alloc_low_pages(unsigned int num) } /* - * By default need 3 4k for initial PMD_SIZE, 3 4k for 0-ISA_END_ADDRESS. - * With KASLR memory randomization, depending on the machine e820 memory - * and the PUD alignment. We may need twice more pages when KASLR memory + * By default need to be able to allocate page tables below PGD firstly for + * the 0-ISA_END_ADDRESS range and secondly for the initial PMD_SIZE mapping. + * With KASLR memory randomization, depending on the machine e820 memory and the + * PUD alignment, twice that many pages may be needed when KASLR memory * randomization is enabled. */ + +#ifndef CONFIG_X86_5LEVEL +#define INIT_PGD_PAGE_TABLES 3 +#else +#define INIT_PGD_PAGE_TABLES 4 +#endif + #ifndef CONFIG_RANDOMIZE_MEMORY -#define INIT_PGD_PAGE_COUNT 6 +#define INIT_PGD_PAGE_COUNT (2 * INIT_PGD_PAGE_TABLES) #else -#define INIT_PGD_PAGE_COUNT 12 +#define INIT_PGD_PAGE_COUNT (4 * INIT_PGD_PAGE_TABLES) #endif + #define INIT_PGT_BUF_SIZE (INIT_PGD_PAGE_COUNT * PAGE_SIZE) RESERVE_BRK(early_pgt_alloc, INIT_PGT_BUF_SIZE); void __init early_alloc_pgt_buf(void) |