Ingo Molnar wrote:
* Jeremy Fitzhardinge <[EMAIL PROTECTED]> wrote:
This isn't correct, because it will set _PAGE_GLOBAL on 32-bit
unconditionally. It needs to be something like:
hm, why is that a problem? Ah, the VDSO page must not be global-mapped,
right? It's getting late here, i should stop modifying the kernel ;)
No, because old processors don't support global pages, and the 32-bit
setup code makes sure to only set _PAGE_GLOBAL in __PAGE_KERNEL once it
has been identified, whereas 64-bit can assume its always present.
Erk. Hm. The old pgtable_64.h defines both PAGE_KERNEL_VSYSCALL, which
is global, and PAGE_KERNEL_VSYSCALL32 which is not. However, it looks
like PAGE_KERNEL_VSYSCALL is used exactly once in setting up a fixmap,
and PAGE_KERNEL_VSYSCALL32 is not used at all.
+#define GLOBAL_PGPROT(prot) __pgprot(prot | _PAGE_GLOBAL)
+
+#define PAGE_KERNEL GLOBAL_PGPROT(__PAGE_KERNEL)
+#define PAGE_KERNEL_RO GLOBAL_PGPROT(__PAGE_KERNEL_RO)
+#define PAGE_KERNEL_EXEC GLOBAL_PGPROT(__PAGE_KERNEL_EXEC)
+#define PAGE_KERNEL_RX GLOBAL_PGPROT(__PAGE_KERNEL_RX)
+#define PAGE_KERNEL_NOCACHE GLOBAL_PGPROT(__PAGE_KERNEL_NOCACHE)
+#define PAGE_KERNEL_LARGE GLOBAL_PGPROT(__PAGE_KERNEL_LARGE)
+#define PAGE_KERNEL_LARGE_EXEC GLOBAL_PGPROT(__PAGE_KERNEL_LARGE_EXEC)
+#define PAGE_KERNEL_VSYSCALL GLOBAL_PGPROT(__PAGE_KERNEL_VSYSCALL)
+#define PAGE_KERNEL_VSYSCALL_NOCACHE
GLOBAL_PGPROT(__PAGE_KERNEL_VSYSCALL_NOCACHE)
i suspect you wanted to make GLOBAL_PGPROT a NOP on 32-bit?
Yeah, cut'n'paste from a stale buffer.
but i think it would be better to just do this distinction for the
PAGE_KERNEL_VSYSCALL?
? The _PAGE_GLOBAL issue is distinct from the VSYSCALL one.
J
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