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| author | Ingo Molnar | 2008-01-30 13:34:04 +0100 |
|---|---|---|
| committer | Ingo Molnar | 2008-01-30 13:34:04 +0100 |
| commit | 687c4825b6ccab69b85f266ae925500b27aab6c2 (patch) | |
| tree | 0e1392fd4313e686a4574a5afa9f180332193a87 /arch/x86/mm | |
| parent | x86: add PG_LEVEL enum (diff) | |
| download | kernel-qcow2-linux-687c4825b6ccab69b85f266ae925500b27aab6c2.tar.gz kernel-qcow2-linux-687c4825b6ccab69b85f266ae925500b27aab6c2.tar.xz kernel-qcow2-linux-687c4825b6ccab69b85f266ae925500b27aab6c2.zip | |
x86: keep the BIOS area executable
keep the BIOS area executable.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/mm')
| -rw-r--r-- | arch/x86/mm/pageattr.c | 29 |
1 files changed, 22 insertions, 7 deletions
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 4589a1382fa1..effcd78d5f40 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -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); @@ -140,13 +161,7 @@ repeat: 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))); |