[PATCH] ARM: Implement copy_to_user_page() for noMMU

Russell King - ARM Linux linux at arm.linux.org.uk
Tue Mar 30 03:29:19 EDT 2010


On Tue, Mar 30, 2010 at 02:31:32AM +0100, Jamie Lokier wrote:
> Other variations such as writing when a mapping is !VM_EXEC and later
> mapping or mprotecting the same shmem VM_EXEC, but it's even more
> forbidden semantically to write to a read-only mapping (and just as
> unchecked on nommu), and conversion of writable to VM_EXEC ought to
> flush i-cache at mprotect time.

If NX isn't implemented, then arm_elf_read_implies_exec() must return 1
for the CPU - so that any region that is marked readable will have
VM_EXEC set.



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