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    Subject[PATCH V5 10/50] x86: Replace PTI_PGTABLE_SWITCH_BIT with PTI_USER_PGTABLE_BIT
    Date
    From: Lai Jiangshan <laijs@linux.alibaba.com>

    They are the same in meaning and value.

    Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
    ---
    arch/x86/include/asm/pgtable.h | 13 +++----------
    1 file changed, 3 insertions(+), 10 deletions(-)

    diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
    index 65542106464b..c8909457574a 100644
    --- a/arch/x86/include/asm/pgtable.h
    +++ b/arch/x86/include/asm/pgtable.h
    @@ -5,6 +5,7 @@
    #include <linux/mem_encrypt.h>
    #include <asm/page.h>
    #include <asm/pgtable_types.h>
    +#include <asm/processor-flags.h>

    /*
    * Macro to mark a page protection value as UC-
    @@ -1164,14 +1165,6 @@ static inline bool pgdp_maps_userspace(void *__ptr)
    static inline int pgd_large(pgd_t pgd) { return 0; }

    #ifdef CONFIG_PAGE_TABLE_ISOLATION
    -/*
    - * All top-level PAGE_TABLE_ISOLATION page tables are order-1 pages
    - * (8k-aligned and 8k in size). The kernel one is at the beginning 4k and
    - * the user one is in the last 4k. To switch between them, you
    - * just need to flip the 12th bit in their addresses.
    - */
    -#define PTI_PGTABLE_SWITCH_BIT PAGE_SHIFT
    -
    /*
    * This generates better code than the inline assembly in
    * __set_bit().
    @@ -1193,12 +1186,12 @@ static inline void *ptr_clear_bit(void *ptr, int bit)

    static inline pgd_t *kernel_to_user_pgdp(pgd_t *pgdp)
    {
    - return ptr_set_bit(pgdp, PTI_PGTABLE_SWITCH_BIT);
    + return ptr_set_bit(pgdp, PTI_USER_PGTABLE_BIT);
    }

    static inline pgd_t *user_to_kernel_pgdp(pgd_t *pgdp)
    {
    - return ptr_clear_bit(pgdp, PTI_PGTABLE_SWITCH_BIT);
    + return ptr_clear_bit(pgdp, PTI_USER_PGTABLE_BIT);
    }
    #endif /* CONFIG_PAGE_TABLE_ISOLATION */

    --
    2.19.1.6.gb485710b
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