diff options
| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2018-02-14 21:25:39 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-02-16 10:48:48 +0100 |
| commit | 6f9dd329717f696f578347c0781a0247db957596 (patch) | |
| tree | 8b9a5d63f9a6c3d221b9bef15f9081c24311f83b /arch/x86/kernel/head_64.S | |
| parent | 9b46a051e43461a9afda2bdd50e0e0ae349341df (diff) | |
x86/mm: Support boot-time switching of paging modes in the early boot code
Early boot code should be able to initialize page tables for both 4- and
5-level paging modes.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214182542.69302-7-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/head_64.S')
| -rw-r--r-- | arch/x86/kernel/head_64.S | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index d3f8b43d541a..145d7b95ae29 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -124,7 +124,10 @@ ENTRY(secondary_startup_64) /* Enable PAE mode, PGE and LA57 */ movl $(X86_CR4_PAE | X86_CR4_PGE), %ecx #ifdef CONFIG_X86_5LEVEL + testl $1, pgtable_l5_enabled(%rip) + jz 1f orl $X86_CR4_LA57, %ecx +1: #endif movq %rcx, %cr4 @@ -372,12 +375,7 @@ GLOBAL(name) __INITDATA NEXT_PGD_PAGE(early_top_pgt) - .fill 511,8,0 -#ifdef CONFIG_X86_5LEVEL - .quad level4_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE_NOENC -#else - .quad level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE_NOENC -#endif + .fill 512,8,0 .fill PTI_USER_PGD_FILL,8,0 NEXT_PAGE(early_dynamic_pgts) |