diff options
| author | Arvind Sankar <nivedita@alum.mit.edu> | 2020-10-10 15:11:10 -0400 |
|---|---|---|
| committer | Borislav Petkov <bp@suse.de> | 2020-10-19 12:47:21 +0200 |
| commit | e5ceb9a02402b984feecb95a82239be151c9f4e2 (patch) | |
| tree | c0ea17ca8e1d466a48abb1c37f4c67a3bf3fc7da /arch/x86/boot/compressed/kaslr.c | |
| parent | da9803dfd3955bd2f9909d55e23f188ad76dbe58 (diff) | |
x86/boot/64: Initialize 5-level paging variables earlier
Commit
ca0e22d4f011 ("x86/boot/compressed/64: Always switch to own page table")
started using a new set of pagetables even without KASLR.
After that commit, initialize_identity_maps() is called before the
5-level paging variables are setup in choose_random_location(), which
will not work if 5-level paging is actually enabled.
Fix this by moving the initialization of __pgtable_l5_enabled,
pgdir_shift and ptrs_per_p4d into cleanup_trampoline(), which is called
immediately after the finalization of whether the kernel is executing
with 4- or 5-level paging. This will be earlier than anything that might
require those variables, and keeps the 4- vs 5-level paging code all in
one place.
Fixes: ca0e22d4f011 ("x86/boot/compressed/64: Always switch to own page table")
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Tested-by: Joerg Roedel <jroedel@suse.de>
Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: https://lkml.kernel.org/r/20201010191110.4060905-1-nivedita@alum.mit.edu
Diffstat (limited to 'arch/x86/boot/compressed/kaslr.c')
| -rw-r--r-- | arch/x86/boot/compressed/kaslr.c | 8 |
1 files changed, 0 insertions, 8 deletions
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index b59547ce5b19..b92fffbe761f 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -840,14 +840,6 @@ void choose_random_location(unsigned long input, return; } -#ifdef CONFIG_X86_5LEVEL - if (__read_cr4() & X86_CR4_LA57) { - __pgtable_l5_enabled = 1; - pgdir_shift = 48; - ptrs_per_p4d = 512; - } -#endif - boot_params->hdr.loadflags |= KASLR_FLAG; if (IS_ENABLED(CONFIG_X86_32)) |