[PATCH 1/4] x86/mm: surround level4_kernel_pgt with #ifdef CONFIG_X86_5LEVEL...#endif
From: Du Changbin <hidden>
Date: 2018-10-18 16:26:19
Also in:
linux-kbuild, lkml
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: Changbin Du <redacted> 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 <redacted> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> --- 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 9c85b54bf03c..9333f7fa5bdb 100644
--- a/arch/x86/include/asm/pgtable_64.h
+++ b/arch/x86/include/asm/pgtable_64.h@@ -16,7 +16,9 @@ #include <linux/threads.h> #include <asm/fixmap.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 ddee1f0870c4..4a59ef93c258 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c@@ -151,16 +151,15 @@ 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;
--
2.17.1