On 27/03/16 19:23, Aneesh Kumar K.V wrote: > PS3 had used PPP bit hack to implement a read only mapping in the > kernel area. Since we are bolt mapping the ioremap area, it used > the pte flags _PAGE_PRESENT | _PAGE_USER to get a PPP value of 0x3 > there by resulting in a read only mapping. This means the area > can be accessed by user space, but kernel will never return such an > address to user space. > > But we can do better by implementing a read only kernel mapping using > PPP bits 0b110 Looks good!
Acked-by: Balbir Singh <bsinghar...@gmail.com> _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
