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| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2018-02-14 14:16:53 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-02-14 13:11:14 +0100 |
| commit | c65e774fb3f6af212641538694b9778ff9ab4300 (patch) | |
| tree | 3c4da88dd0658874ea3fc7de3cc96ee27d711ef9 /arch/x86/mm/init_64.c | |
| parent | 5c7919bb1994f8dc7fed219a5db09e6bb9d473a5 (diff) | |
| download | linux-c65e774fb3f6af212641538694b9778ff9ab4300.tar.bz2 | |
x86/mm: Make PGDIR_SHIFT and PTRS_PER_P4D variable
For boot-time switching between 4- and 5-level paging we need to be able
to fold p4d page table level at runtime. It requires variable
PGDIR_SHIFT and PTRS_PER_P4D.
The change doesn't affect the kernel image size much:
text data bss dec hex filename
8628091 4734304 1368064 14730459 e0c4db vmlinux.before
8628393 4734340 1368064 14730797 e0c62d vmlinux.after
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
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/20180214111656.88514-7-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/mm/init_64.c')
| -rw-r--r-- | arch/x86/mm/init_64.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 1ab42c852069..6a4b20bc7527 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -143,7 +143,7 @@ void sync_global_pgds(unsigned long start, unsigned long end) * With folded p4d, pgd_none() is always false, we need to * handle synchonization on p4d level. */ - BUILD_BUG_ON(pgd_none(*pgd_ref)); + MAYBE_BUILD_BUG_ON(pgd_none(*pgd_ref)); p4d_ref = p4d_offset(pgd_ref, addr); if (p4d_none(*p4d_ref)) |