From: Changbin Du <changbin.du@xxxxxxxxx> The level4_kernel_pgt is only defined when X86_5LEVEL is enabled. So surround level4_kernel_pgt with #ifdef CONFIG_X86_5LEVEL...#endif to make code correct. Signed-off-by: Changbin Du <changbin.du@xxxxxxxxx> --- arch/x86/include/asm/pgtable_64.h | 2 ++ arch/x86/kernel/head64.c | 13 ++++++------- 2 files changed, 8 insertions(+), 7 deletions(-) diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h index 877bc27..9e7f667 100644 --- a/arch/x86/include/asm/pgtable_64.h +++ b/arch/x86/include/asm/pgtable_64.h @@ -15,7 +15,9 @@ #include <linux/bitops.h> #include <linux/threads.h> +#ifdef CONFIG_X86_5LEVEL extern p4d_t level4_kernel_pgt[512]; +#endif extern p4d_t level4_ident_pgt[512]; extern pud_t level3_kernel_pgt[512]; extern pud_t level3_ident_pgt[512]; diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index 0c408f8..775d7a6 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -143,16 +143,15 @@ unsigned long __head __startup_64(unsigned long physaddr, pgd = fixup_pointer(&early_top_pgt, physaddr); p = pgd + pgd_index(__START_KERNEL_map); - if (la57) - *p = (unsigned long)level4_kernel_pgt; - else - *p = (unsigned long)level3_kernel_pgt; - *p += _PAGE_TABLE_NOENC - __START_KERNEL_map + load_delta; - +#ifdef CONFIG_X86_5LEVEL if (la57) { + *p = (unsigned long)level4_kernel_pgt; p4d = fixup_pointer(&level4_kernel_pgt, physaddr); p4d[511] += load_delta; - } + } else +#endif + *p = (unsigned long)level3_kernel_pgt; + *p += _PAGE_TABLE_NOENC - __START_KERNEL_map + load_delta; pud = fixup_pointer(&level3_kernel_pgt, physaddr); pud[510] += load_delta; -- 2.7.4