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x86: unify noexec handling

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This patch unifies noexec handling on 32-bit and 64-bit.

[ Impact: cleanup ]

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
[ mingo@elte.hu: build fix ]
LKML-Reference: <1240303167.771.69.camel@penberg-laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Pekka Enberg
2009-04-21 11:39:27 +03:00
committed by Ingo Molnar
parent 8ecee4620e
commit 89388913f2
4 changed files with 63 additions and 90 deletions
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52
arch/x86/mm/init_32.c
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@ -587,61 +587,9 @@ void zap_low_mappings(void)
flush_tlb_all();
}
int nx_enabled;
pteval_t __supported_pte_mask __read_mostly = ~(_PAGE_NX | _PAGE_GLOBAL | _PAGE_IOMAP);
EXPORT_SYMBOL_GPL(__supported_pte_mask);
#ifdef CONFIG_X86_PAE
static int disable_nx __initdata;
/*
* noexec = on|off
*
* Control non executable mappings.
*
* on Enable
* off Disable
*/
static int __init noexec_setup(char *str)
{
if (!str || !strcmp(str, "on")) {
if (cpu_has_nx) {
__supported_pte_mask |= _PAGE_NX;
disable_nx = 0;
}
} else {
if (!strcmp(str, "off")) {
disable_nx = 1;
__supported_pte_mask &= ~_PAGE_NX;
} else {
return -EINVAL;
}
}
return 0;
}
early_param("noexec", noexec_setup);
void __init set_nx(void)
{
unsigned int v[4], l, h;
if (cpu_has_pae && (cpuid_eax(0x80000000) > 0x80000001)) {
cpuid(0x80000001, &v[0], &v[1], &v[2], &v[3]);
if ((v[3] & (1 << 20)) && !disable_nx) {
rdmsr(MSR_EFER, l, h);
l |= EFER_NX;
wrmsr(MSR_EFER, l, h);
nx_enabled = 1;
__supported_pte_mask |= _PAGE_NX;
}
}
}
#endif
/* user-defined highmem size */
static unsigned int highmem_pages = -1;