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| author |   Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2018-02-14 21:25:35 +0300 |
|---|---|---|
| committer |   Ingo Molnar <mingo@kernel.org> | 2018-02-16 10:48:47 +0100 |
| commit | b16e770bfa5344f1cd4f7b4ecd7bbae25001e120 (patch) | |
| tree | 47ba333dc01234e8e5d026296536d58b56a2b76f /arch/x86/kernel/head64.c | |
| parent | x86/mm: Initialize 'pgtable_l5_enabled' at boot-time (diff) | |
| download | linux-dev-b16e770bfa5344f1cd4f7b4ecd7bbae25001e120.tar.xz linux-dev-b16e770bfa5344f1cd4f7b4ecd7bbae25001e120.zip | |
x86/mm: Initialize 'pgdir_shift' and 'ptrs_per_p4d' at boot-time
Switching between paging modes requires the folding of the p4d page table level
when we only have 4 paging levels, which means we need to adjust 'pgdir_shift'
and 'ptrs_per_p4d' during early boot according to paging mode.
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/20180214182542.69302-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/head64.c')
| -rw-r--r-- | arch/x86/kernel/head64.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index ffb31c50d515..8a0a485524da 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -42,9 +42,9 @@ pmdval_t early_pmd_flags = __PAGE_KERNEL_LARGE & ~(_PAGE_GLOBAL | _PAGE_NX); #ifdef CONFIG_X86_5LEVEL unsigned int pgtable_l5_enabled __ro_after_init; EXPORT_SYMBOL(pgtable_l5_enabled); -unsigned int pgdir_shift __ro_after_init = 48; +unsigned int pgdir_shift __ro_after_init = 39; EXPORT_SYMBOL(pgdir_shift); -unsigned int ptrs_per_p4d __ro_after_init = 512; +unsigned int ptrs_per_p4d __ro_after_init = 1; EXPORT_SYMBOL(ptrs_per_p4d); #endif @@ -79,6 +79,8 @@ static void __head check_la57_support(unsigned long physaddr) return; *fixup_int(&pgtable_l5_enabled, physaddr) = 1; + *fixup_int(&pgdir_shift, physaddr) = 48; + *fixup_int(&ptrs_per_p4d, physaddr) = 512; } #else static void __head check_la57_support(unsigned long physaddr) {} |