[PATCH v13 19/24] selftests/vm: associate key on a mapped page and detect access violation

[Dave Hansen]

On 06/13/2018 05:45 PM, Ram Pai wrote:
> +void test_read_of_access_disabled_region_with_page_already_mapped(int *ptr,
> +		u16 pkey)
> +{
> +	int ptr_contents;
> +
> +	dprintf1("disabling access to PKEY[%02d], doing read @ %p\n",
> +				pkey, ptr);
> +	ptr_contents = read_ptr(ptr);
> +	dprintf1("reading ptr before disabling the read : %d\n",
> +			ptr_contents);
> +	read_pkey_reg();
> +	pkey_access_deny(pkey);
> +	ptr_contents = read_ptr(ptr);
> +	dprintf1("*ptr: %d\n", ptr_contents);
> +	expected_pkey_fault(pkey);
> +}

Looks fine to me.  I'm a bit surprised we didn't do this already, which
is a good thing for this patch.

FWIW, if you took patches like this and put them first, you could
probably get it merged now.  Yes, I know it would mean redoing some of
the later code move and rename ones.