Re: [PATCHv7 08/19] x86/mm: Make PGDIR_SHIFT and PTRS_PER_P4D variable

[Kirill A. Shutemov]

On Mon, Sep 18, 2017 at 10:55:42AM +0000, Kirill A. Shutemov wrote:
> 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
> 10710172        4879964  860160 16450296         fb02f8 vmlinux.before
> 10710340        4880000  860160 16450500         fb03c4 vmlinux.after
> 
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>

Fixup for the patch:

diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c
index a1d983a45ab0..10dcbec70ef9 100644
--- a/arch/x86/mm/dump_pagetables.c
+++ b/arch/x86/mm/dump_pagetables.c
@@ -428,7 +428,7 @@ static void walk_p4d_level(struct seq_file *m, struct pg_state *st, pgd_t addr,
 }
 
 #define pgd_large(a) (pgtable_l5_enabled ? pgd_large(a) : p4d_large(__p4d(pgd_val(a))))
-#define pgd_none(a)  (pgtable_l5_enabled ? pgd_none(a) : pgd_none(a))
+#define pgd_none(a)  (pgtable_l5_enabled ? pgd_none(a) : p4d_none(__p4d(pgd_val(a))))
 
 static inline bool is_hypervisor_range(int idx)
 {
-- 
 Kirill A. Shutemov