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yaml
---
r: 80499
b: refs/heads/master
c: 687c482
h: refs/heads/master
i:
  80497: e966604
  80495: 3ff01cc
v: v3
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Ingo Molnar committed Jan 30, 2008
1 parent 57012de commit 0f38bd9
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Showing 2 changed files with 23 additions and 8 deletions.
2 changes: 1 addition & 1 deletion [refs]
Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: 30551bb3ce9257a2352b3cb4e45010d415cc0ad5
refs/heads/master: 687c4825b6ccab69b85f266ae925500b27aab6c2
29 changes: 22 additions & 7 deletions trunk/arch/x86/mm/pageattr.c
Original file line number Diff line number Diff line change
Expand Up @@ -22,6 +22,27 @@ void clflush_cache_range(void *addr, int size)
#include <asm/uaccess.h>
#include <asm/pgalloc.h>

/*
* We allow the BIOS range to be executable:
*/
#define BIOS_BEGIN 0x000a0000
#define BIOS_END 0x00100000

static inline pgprot_t check_exec(pgprot_t prot, unsigned long address)
{
if (__pa(address) >= BIOS_BEGIN && __pa(address) < BIOS_END)
pgprot_val(prot) &= ~_PAGE_NX;
/*
* Better fail early if someone sets the kernel text to NX.
* Does not cover __inittext
*/
BUG_ON(address >= (unsigned long)&_text &&
address < (unsigned long)&_etext &&
(pgprot_val(prot) & _PAGE_NX));

return prot;
}

pte_t *lookup_address(unsigned long address, int *level)
{
pgd_t *pgd = pgd_offset_k(address);
Expand Down Expand Up @@ -140,13 +161,7 @@ __change_page_attr(unsigned long address, struct page *page, pgprot_t prot)
BUG_ON(PageLRU(kpte_page));
BUG_ON(PageCompound(kpte_page));

/*
* Better fail early if someone sets the kernel text to NX.
* Does not cover __inittext
*/
BUG_ON(address >= (unsigned long)&_text &&
address < (unsigned long)&_etext &&
(pgprot_val(prot) & _PAGE_NX));
prot = check_exec(prot, address);

if (level == PG_LEVEL_4K) {
set_pte_atomic(kpte, mk_pte(page, canon_pgprot(prot)));
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