Re: [PATCH v4] RO/NX protection for loadable kernel modules

[Siarhei Liakh <sliakh.lkml@gmail.com>]

> I like it, you can already put
>
> Acked-by: Arjan van de Ven <arjan@linux.intel.com>

Thanks, I will add this to V5.

...
>> +             /*Set text RO if there are still pages between begin
>> and end*/
>> +             if (end_addr > begin_addr) {
>> +                     pg_count = PFN_DOWN(end_addr - 1) -
>> +                                     PFN_DOWN(begin_addr) + 1;
>> +                     DEBUGP("  RO: 0x%lx %lu\n", begin_addr,
>> pg_count);
>> +                     set_memory_ro(begin_addr, pg_count);
>> +             } else {
...
> I *think* this can be done as
>
> begin_pfn = PFN_UP( (base);
> end_pfn = PFN_DOWN(base + ro_size);
>
> if (end_pfn > begin_pfn)
>        set_memory_ro(begin_pfn >> PAGE_SHIFT, end_pfn - begin_pfn);
>
> (note that I think the +1 you have might be buggy)

The +1 is necessary because of (end_addr - 1). However, I like your
way better, so I will incorporate it in V5.