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| author | Rusty Russell <rusty@rustcorp.com.au> | 2008-07-22 15:40:46 +1000 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-07-22 10:41:18 +0200 |
| commit | c2e3277f875b83e5adc34e96989d6d87ec5f80f7 (patch) | |
| tree | c25f6dd50e136d720f8f35d689946b6d256d054b | |
| parent | 988781dc3e1d9209192b04458d279815923f5e76 (diff) | |
| download | linux-c2e3277f875b83e5adc34e96989d6d87ec5f80f7.tar.bz2 | |
x86: fix pte_flags() to only return flags, fix lguest (updated)
(Jeremy said:
rusty: use PTE_MASK
rusty: use PTE_MASK
rusty: use PTE_MASK
When I asked:
jsgf: does that include the NX flag?
He responded eloquently:
rusty: use PTE_MASK
rusty: use PTE_MASK
yes, it's the official constant of masking flags out of ptes
)
Change a15af1c9ea2750a9ff01e51615c45950bad8221b 'x86/paravirt: add
pte_flags to just get pte flags' removed lguest's private pte_flags()
in favor of a generic one.
Unfortunately, the generic one doesn't filter out the non-flags bits:
this results in lguest creating corrupt shadow page tables and blowing
up host memory.
Since noone is supposed to use the pfn part of pte_flags(), it seems
safest to always do the filtering.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-and-morning-tea-spilled-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | arch/x86/kernel/paravirt.c | 2 | ||||
| -rw-r--r-- | include/asm-x86/page.h | 7 | ||||
| -rw-r--r-- | include/asm-x86/paravirt.h | 3 |
3 files changed, 10 insertions, 2 deletions
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index 097d8a6797fa..94da4d52d798 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -443,7 +443,7 @@ struct pv_mmu_ops pv_mmu_ops = { #endif /* PAGETABLE_LEVELS >= 3 */ .pte_val = native_pte_val, - .pte_flags = native_pte_val, + .pte_flags = native_pte_flags, .pgd_val = native_pgd_val, .make_pte = native_make_pte, diff --git a/include/asm-x86/page.h b/include/asm-x86/page.h index 28d7b4533b1a..05d9bea2bfd5 100644 --- a/include/asm-x86/page.h +++ b/include/asm-x86/page.h @@ -144,6 +144,11 @@ static inline pteval_t native_pte_val(pte_t pte) return pte.pte; } +static inline pteval_t native_pte_flags(pte_t pte) +{ + return native_pte_val(pte) & ~PTE_MASK; +} + #define pgprot_val(x) ((x).pgprot) #define __pgprot(x) ((pgprot_t) { (x) } ) @@ -165,7 +170,7 @@ static inline pteval_t native_pte_val(pte_t pte) #endif #define pte_val(x) native_pte_val(x) -#define pte_flags(x) native_pte_val(x) +#define pte_flags(x) native_pte_flags(x) #define __pte(x) native_make_pte(x) #endif /* CONFIG_PARAVIRT */ diff --git a/include/asm-x86/paravirt.h b/include/asm-x86/paravirt.h index aec9767836b6..5ca4639dc7dd 100644 --- a/include/asm-x86/paravirt.h +++ b/include/asm-x86/paravirt.h @@ -1088,6 +1088,9 @@ static inline pteval_t pte_flags(pte_t pte) ret = PVOP_CALL1(pteval_t, pv_mmu_ops.pte_flags, pte.pte); +#ifdef CONFIG_PARAVIRT_DEBUG + BUG_ON(ret & PTE_MASK); +#endif return ret; } |