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x86_32, mm: Remove user bit from identity map PDE

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The only reason that the user bit was set was to support userspace
access to the compat vDSO in the fixmap.  The compat vDSO is gone,
so the user bit can be removed.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/e240a977f3c7cbd525a091fd6521499ec4b8e94f.1394751608.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This commit is contained in:
Andy Lutomirski 2014-03-13 16:01:27 -07:00 committed by H. Peter Anvin
parent b0b49f2673
commit 7dda038756
1 changed files with 1 additions and 6 deletions
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7
arch/x86/include/asm/pgtable_types.h
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@ -214,13 +214,8 @@
#ifdef CONFIG_X86_64
#define __PAGE_KERNEL_IDENT_LARGE_EXEC __PAGE_KERNEL_LARGE_EXEC
#else
/*
* For PDE_IDENT_ATTR include USER bit. As the PDE and PTE protection
* bits are combined, this will alow user to access the high address mapped
* VDSO in the presence of CONFIG_COMPAT_VDSO
*/
#define PTE_IDENT_ATTR 0x003 /* PRESENT+RW */
#define PDE_IDENT_ATTR 0x067 /* PRESENT+RW+USER+DIRTY+ACCESSED */
#define PDE_IDENT_ATTR 0x063 /* PRESENT+RW+DIRTY+ACCESSED */
#define PGD_IDENT_ATTR 0x001 /* PRESENT (no other attributes) */
#endif